# Science behind wax and sealant finishes



## Incubus (Jul 16, 2007)

So, there's a knobber asking how a few microns of wax can make a glossy/deep/wet etc finish and a few microns of sealant can make a crystal clear/reflective/etc finish.

I've made him read the polishbliss article on LSP's, but he's not buying it.

Does anyone have any good hard scientific information to shut him up?


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## Clark @ PB (Mar 1, 2006)

Just dont bother, I find if they dont want to learn there's no point trying to tell them otherwise lol


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## Incubus (Jul 16, 2007)

fair do's 

p.s. I went to school with you


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## Jesse74 (Jul 19, 2008)

Clark said:


> Just dont bother, I find if they dont want to learn there's no point trying to tell them otherwise lol


Exactly... these kind of people are not even worth the time. I've had customers like that in the past and I refuse to clean their cars again; it's just not worth their interrogations and disbelief.


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## Clark @ PB (Mar 1, 2006)

Incubus said:


> fair do's
> 
> p.s. I went to school with you


Oh really?


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## Dave KG (Feb 23, 2006)

Incubus said:


> So, there's a knobber asking how a few microns of wax can make a glossy/deep/wet etc finish and a few microns of sealant can make a crystal clear/reflective/etc finish.
> 
> I've made him read the polishbliss article on LSP's, but he's not buying it.
> 
> Does anyone have any good hard scientific information to shut him up?


You are enterring here into the realms of very open debate as to me, reading as a physicist with a rather objective eye, there is no hard scientific fact to suggest that a few microns (and its not even that, an LSP layer is submicron typically) can enhance the finish on a car. Indeed this is bourne out in practice and demonstrated many times that adding an LSP to a perfectly prepped finish makes little if any tenable difference.

What you can get is a very subtle nuance added to the paint, but dont expect massive differences as they simply are not there - in practice, and this is justified by the science.

How do you see what you see? Light enterring your eye. So, you see red paint because white light reflects off the paint and the paint absorbs all colours and reflects red and you then see the red (in a simple sense). Now, adding a submicron layer of a "clear" film to the paint finish introduces another boundary of different refective index... so the light goes from air, through the wax layer, through the clearcoat layer, bounces, and returns through these layers... Each layer will change the light as it travels through it by altering its direction, and its wavelength... Typical light wavelength in air is around 400 - 700nm (0.4um to 0.7um). Is this of the order of the thickness of an LSP layer? I suspect the thickness is of the order of the wavelength in the wax medium and from this one would suspect that you can get multiple reflections from boundaries interfering constructively to give an enhanced reflection. However, if this indeed does happen you will reduce the light to the colour coat and take away from the colour intensity (which we know does not happen to a tenable level). Further, this effect will rely on even layers - and the paint is not even and neither will the LSP layer.

If you want to consider the effects from a scientific standpoint, for me this is the route of reasoning you would want to take - look at it from a physical perspective and as a first approximation, assume the light travels in rays (ray optics)... this will get you only so far and dont take the results too seriously as that is just an approximation. You will need to know the refractive index for starters of the paint, lsp layer. However, you can go a lot deeper than just this.

Or - look at some more experimental evidence, more and more of which is building to suggest, despite claims, that LSPs really dont make a tenable difference to the looks of a well prepped finish. I believe this to be true from my own experimentation, and that while you can get a subtle nuance here and there, ultimately there is no big difference between them in looks when the preparation is done correctly.

As said though, you will get many arguments on this - best to analyse them, and anything you read from an objective scientific standpoint if you are wanting a scientific answer and then go with what _you_ believe.


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## Troon (Dec 17, 2008)

We need a "blind" comparison test (i.e. viewers don't know which product is which) of waxes to see if the difference is visible. Hang on - didn't someone on here do that with some Astras a while back? Did that show any appreciable difference?

If not, then wax is only worth buying based on durability, beading/sheeting and ease of application.

This reminds me of speaker cable debates over in the audiophile world, where the golden-ears are still having a hard time accepting that the best solution is thick copper.


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## Rich @ PB (Oct 26, 2005)

For anyone reading whose interested, Dave and I have had several lengthly discussions on this subject in the past, and we disagree quite strongly. It is my firm believe, based on what I see day in day out in our studio, that LSP choice makes a small but significant difference to the overall look of paint. I first experienced this on my old silver Leon, spending hundreds on products until I found a system that produced a genuinely different and gobsmacking result, that far exceeded previous results, and that I haven't been able to recreate with any other LSP products or systems. Compare Werkstat Acrylic with Zymöl Vintage on a solid black car and there will be a highly noticeable difference in the sharpness of the finish, compare the same products on any light metallic finish and again, reflectivity will be noticeably better on the car treated with Werkstat. I could go on, but our thoughts on what works best and why on most popular colours is outlined in our new online FAQ. It is very interesting that the detailing community is divided on this issue, but I guess everyone's eyes are different, so I am happy to accept others may not see much (if any) difference between different LSP finishes, but for us, it's very important to our work and the art we produce.


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## Dave KG (Feb 23, 2006)

Troon said:


> We need a "blind" comparison test (i.e. viewers don't know which product is which) of waxes to see if the difference is visible. Hang on - didn't someone on here do that with some Astras a while back? Did that show any appreciable difference?
> 
> If not, then wax is only worth buying based on durability, beading/sheeting and ease of application.
> 
> This reminds me of speaker cable debates over in the audiophile world, where the golden-ears are still having a hard time accepting that the best solution is thick copper.


Yes, this was done - on seven black Corsas...

The results showed nothing more than a natural statistical variation in what people reported back with many saying they could see no tenable difference in the finishes - includinng waxes and sealents.

Major evidence, IMHO, that supports the argument that LSPs make little if any tenable difference.


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## Clark @ PB (Mar 1, 2006)

This is where the debate will go on and on. I know what my eyes tell me and no one will tell me differently, so it's always going to be a matter of personal opinion.


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## Dave KG (Feb 23, 2006)

WX51 TXR said:


> For anyone reading whose interested, Dave and I have had several lengthly discussions on this subject in the past, and we disagree quite strongly. It is my firm believe, based on what I see day in day out in our studio, that LSP choice makes a small but significant difference to the overall look of paint. I first experienced this on my old silver Leon, spending hundreds on products until I found a system that produced a genuinely different and gobsmacking result, that far exceeded previous results, and that I haven't been able to recreate with any other LSP products or systems. Compare Werkstat Acrylic with Zymöl Vintage on a solid black car and there will be a highly noticeable difference in the sharpness of the finish, compare the same products on any light metallic finish and again, reflectivity will be noticeably better on the car treated with Werkstat. I could go on, but our thoughts on what works best and why on most popular colours is outlined in our new online FAQ. It is very interesting that the detailing community is divided on this issue, but I guess everyone's eyes are different, so I am happy to accept others may not see much (if any) difference between different LSP finishes, but for us, it's very important to our work and the art we produce.


And I am sure that those wanting to search could happily find these discussions burried in the forum somewhere 

It remains my belief, based on my own experiments that have been conducted and what I see on a regular basis also, that the wax and seaent choices make little if any difference to the overall finish on the vehicle, irrespective of colour. Slight nuances, maybe, notable difference certainly not. This is backed up in my own mind with my own scientifc analysis of what is going on, and what we see and how we see it - based from a Physicists point of view though, and I appreciate there is a lot of chemistry in LSPs though I would argue a lot less chemistry in light, sight and perception.

I believe personally that there is more in the physhological element here and what is perceived to be seen rather than what is actually seen. And subtle nuances here and there accelerate this... Its my best explanation for such a divide in the industry between highly respected detailers, and perhaps the reason one is neither right nor wrong regardless of the camp they fall in. From a purely physical point of view, the analysis points to there being little difference and this is indeed backed up by my own experiments which are also well published (and well debated as to their validity, and I have also written much to validate the results as well, and I believe them to be (while carried out in fun) representative and valuable). If we bring human physhology into play, we open up a whole new playing field into the interpretation of what one sees, and how this is affected by wants, beliefs, and desires. I can happily see this accounting for quite a lot of the differences described, though naturally I take on board your own discussions as making many valuable points also.

Will there every be agreement on this? In the same way as there will never be full agreement on the model to best describe light, I dont think there will be and rather we should employ models to best fit the evidence with which we are presented... which is what I have done with my own analysis and why I stand by my belief of there being little if any tenable difference. But as above, is phychology also playing a part in this? Or playing a part in your results? Or both? I turn to a physical argument to justify my own beliefs, but its simplified at this stage but does seem to give me the answer of it making little if any difference... so I will continue to stand by this


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## hotwaxxx (Jul 12, 2007)

WX51 TXR said:


> For anyone reading whose interested, Dave and I have had several lengthly discussions on this subject in the past, and we disagree quite strongly. It is my firm believe, based on what I see day in day out in our studio, that LSP choice makes a small but significant difference to the overall look of paint. I first experienced this on my old silver Leon, spending hundreds on products until I found a system that produced a genuinely different and gobsmacking result, that far exceeded previous results, and that I haven't been able to recreate with any other LSP products or systems. Compare Werkstat Acrylic with Zymöl Vintage on a solid black car and there will be a highly noticeable difference in the sharpness of the finish, compare the same products on any light metallic finish and again, reflectivity will be noticeably better on the car treated with Werkstat. I could go on, but our thoughts on what works best and why on most popular colours is outlined in our new online FAQ. It is very interesting that the detailing community is divided on this issue, but I guess everyone's eyes are different, so I am happy to accept others may not see much (if any) difference between different LSP finishes, but for us, it's very important to our work and the art we produce.


I've seen so much of Clark's and your work Richard, and I have to say the two of you are the pinnacle of pro-detailers for me and are my role models. You've taken detailing to a new level (from the presentability of your unit to your high levels of professionalism) and I just love looking at the transformations you perform on all levels of cars. Okay - I'll stop the gay talk now...:argie:

I've seen you use Werkstat on so many cars and you always bang on about how well it works on silvers/whites (acrylic) and solids (carnabau) and am pretty close to purchasing the two sets from yourselves to test it out myself. I just want to know how you compare it to your other favourite wax of choice - Z Vintage? Is it on a level par and if so, why do you still continue to use other waxes as LSP?


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## Clark @ PB (Mar 1, 2006)

Dave KG said:


> It remains my belief...


I think that pretty much sums it up Dave, it's your belief that there isnt much difference in the LSP's and there are many people who agree with you. On the other hand, it's my belief that they can make a difference and there are many people that will agree with me, so it's always going to be something that will never be set in stone, that i'm sure we will both agree on (for a change) on that :lol:

Just look at all the recent Zaino hype for example. Surely at least some of the rave reviews it gets is down to the fact that people can see a difference?


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## Dave KG (Feb 23, 2006)

Clark said:


> This is where the debate will go on and on. I know what my eyes tell me and no one will tell me differently, so it's always going to be a matter of personal opinion.


Worth debating though, is what amount of what your eyes are telling you are a phycological effects, and what amount is _actually in front of you_? Sounds a silly question, but as above, I believe that owing to any difference there is being very small, it is our brains more than an actual difference that we are seeing. And it is something completely out of our control.

Moving away from rights and wrongs, one should use what they like and stick to it and if the believe something looks better on a particular colour, stick to it!

Moving back to rights and wrongs, a thorough scientific model does not yet exist to prove or disprove either way... Experimental evidence exists supporting both sides of the argument, though for me the evidence supporting the fact that LSPs make little if any difference is stronger. But I would say that, as that is my belief and a lot of the evidence presented to this end is my own so like any good scientist I will defend it... but then I dont believe it needs much defending and the results it shows are very telling and very difficult to just sweep under the carpet to personal opinion.

... so we arrive back at phschology


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## Dave KG (Feb 23, 2006)

Clark said:


> I think that pretty much sums it up Dave, it's your belief that there isnt much difference in the LSP's and there are many people who agree with you. On the other hand, it's my belief that they can make a difference and there are many people that will agree with me, so it's always going to be something that will never be set in stone, that i'm sure we will both agree on (for a change) on that :lol:
> 
> Just look at all the recent Zaino hype for example. Surely at least some of the rave reviews it gets is down to the fact that people can see a difference?


If we agree on this, then we wont have anything to debate :lol::lol:

But seriously, I do believe there are a lot of factors and nobody can really state a right or wrong here with 100% certainty. We will have to base on personal opinion and experimental evidence and half made models thus far, and this leaves the door open for any personal opinion.

Long may things not be set in stone however, as its one of the fun unanswered questions in detailing


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## Dodo Factory (Apr 11, 2007)

There are only going to be two ways an LSP can enhance a clearcoat finish... surface characteristics and depth.

If the surface of the LSP allows for a more microscopically smooth surface (because even glass is pitted when examined under a microscope) and the LSP can fill in the small pores and indents within the clearcoat surface (for it will be attacked and pitted by UV light, stones whatever) then it will reflect light better. It may only need a micron to do this. That is why filling agents can work... they fill in a micron deep swirlmark and improve the optics of the surface.

Also, if the LSP is very deep, then it can give more 'depth' to the surface, but it may also dull the reflection due to light having to travel through it. LSPs aren't usually very thick at all, so this tends to be a characteristic of clearcoats and permanent coatings that are a lot thicker.

The funniest thing about the Fifth Gear 'glossmeter' test is that glossmeters have more foibles than paint thickness gauges. It is routine for a glossmeter to read lower on a surface with an LSP on it, as the light has to travel through the LSP and back again to reflect. So adding an LSP can sometimes make a car less glossy in theory (although the smoothness of some LSPs - often caused by temporary glaze oils that fill very nicely) often allows a temporary increase in gloss levels.

On a machined surface, people will find glaze oils the most evident, followed by the more obvious surface characteristic changes, such as water behaviour.

Good post though, and great debate. Always nice to see Clark and Dave KG tapping away on the same thread as you know the discussion will be good.


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## Rich @ PB (Oct 26, 2005)

Dave KG said:


> And I am sure that those wanting to search could happily find these discussions burried in the forum somewhere
> 
> It remains my belief, based on my own experiments that have been conducted and what I see on a regular basis also, that the wax and seaent choices make little if any difference to the overall finish on the vehicle, irrespective of colour. Slight nuances, maybe, notable difference certainly not. This is backed up in my own mind with my own scientifc analysis of what is going on, and what we see and how we see it - based from a Physicists point of view though, and I appreciate there is a lot of chemistry in LSPs though I would argue a lot less chemistry in light, sight and perception.
> 
> ...


I try not to overanalyse the question. For me, it's simply a case of knowing what one product looks like over another, and deciding what I like best... or determining what the customer wants if at work. Whether the difference I'm able to see is down to the physical or chemical charateristics of the product or physhological effects matters not to me... as long as both the customer and I can agree (and see the same thing), then all is well. Interestingly, the boys on ScoobyNet have frequently reported seeing the same difference as me between Werkstat and Blackfire on the ever popular WR Blue... of course, all this means is that they see the same thing, while the underlying reason is not possible to confirm... _but_ they can see the same effect. For me, that is the important bit, otherwise I'd simply pick one easy to use durable LSP and use it all the time!


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## hotwaxxx (Jul 12, 2007)

This thread is way too complicated for me.

Personally, I believe a wax does deliver a little something. But then I do agree that it is mostly down to preparation even before a wax is applied.


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## Dave KG (Feb 23, 2006)

WX51 TXR said:


> I try not to overanalyse the question. For me, it's simply a case of knowing what one product looks like over another, and deciding what I like best... or determining what the customer wants if at work. Whether the difference I'm able to see is down to the physical or chemical charateristics of the product or physhological effects matters not to me... as long as both the customer and I can agree (and see the same thing), then all is well. Interestingly, the boys on ScoobyNet have frequently reported seeing the same difference as me between Werkstat and Blackfire on the ever popular WR Blue... of course, all this means is that they see the same thing, while the underlying reason is not possible to confirm... _but_ they can see the same effect. For me, that is the important bit, otherwise I'd simply pick one easy to use durable LSP and use it all the time!


Which is all good an well from a practical point of view, and something we all do as detailers... however, being able to understand and answer _why_ differences are there, or if indeed they are there, is to me equally important from a stand point of moving things forward... then if there are differences steps can be taken to enhance them. But I remain unconvinced they are there.

Subaru owners are spotting differenes, DW members did not at the wax test on identical cars (and thats seeing them side by side) - so we have conflicting evidence here as well. Nobody has yet explained _why_, and because of this we have an unaswered question and as detailing is my passion I like to try and answer them... though if I do answer it, no doubt I will feel bored until I get another question!

I understand what you are saying but having conducted experiements here and had conclusiver evidence of there not being a difference, then I must also take this into account alongside any differences people claim are there. If a customer wants a specific effect, then naturally one will take the products which is claimed to give that effect or nuance _and_ that we think we can see ourselved in practice... but owing to such small differences, now we enter the realms of debating what products offer what effects and what people prefer on different colours vary strongly as well.

To me, the evidence supporting no tenable difference remains strong, more convinving to me than evidence to the contrary at the moment and so this is the stand point I take, backed by my own scientific analysis which to me is very important as its this you can use to move things forward in a positive way.


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## Clark @ PB (Mar 1, 2006)

hotwaxxx said:


> I've seen so much of Clark's and your work Richard, and I have to say the two of you are the pinnacle of pro-detailers for me and are my role models. You've taken detailing to a new level (from the presentability of your unit to your high levels of professionalism) and I just love looking at the transformations you perform on all levels of cars. Okay - I'll stop the gay talk now...:argie:
> 
> I've seen you use Werkstat on so many cars and you always bang on about how well it works on silvers/whites (acrylic) and solids (carnabau) and am pretty close to purchasing the two sets from yourselves to test it out myself. I just want to know how you compare it to your other favourite wax of choice - Z Vintage? Is it on a level par and if so, why do you still continue to use other waxes as LSP?


Cheers mate, cheques in the post 

It might be worth taking a look at our FAQ section if you havent already done so as this expresses our views on what other products suit certain colours just in case that maybe helps make your mind up about product choice especially for solids/mid tones etc  :

http://www.polishedbliss.co.uk/acatalog/car-care-advice-faq.html#4.2

Going back to your main question - When comparing Werkstat Acrylic and Vintage on the likes of Silvers and Whites, unless the customer is insistant on Vintage then we'll go for Werkstat. Vintage will give a nice gloss and warmth but in my opinion the sharper, wetter and more reflective look of the sealant looks much better on these particular colours. A good example of this was Rich's silver Leon, where he switched over to Vintage after months of Werkstat and we were both a bit disappointed with the look in all honesty (perhaps we anticipated too much having seen it on darker colours), so it was quickly stripped and Werkstat was re-applied.

My dads 993 Turbo (also silver) previously wore Vintage but now has around 18 layers of Werkstat (overkill or not, who cares! ) and he now swears he can see a noticeable difference in the paint too, in his eyes you can see much more colour in the reflections when compared to before.

We also have a metalic grey Alpina B10 Touring on contract and again, Vintage has been replaced by Werkstat at the owners request due to the difference in looks.

Obviously the one big thing Vintage has going for itself is the awesome durability from one application, whereas you would need around 6-8 coats of Werkstat to achieve the same levels.

As for why we still like to use other waxes, the FAQ should answer that part 

Any more questions feel free to fire me an e-mail mate (my PM's are disabled) :thumb:


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## dantheman (Dec 10, 2007)

Dave KG said:


> It remains my belief, based on my own experiments that have been conducted and what I see on a regular basis also, that the wax and seaent choices make little if any difference to the overall finish on the vehicle, irrespective of colour. Slight nuances, maybe, notable difference certainly not. This is backed up in my own mind with my own scientifc analysis of what is going on, and what we see and how we see it - based from a Physicists point of view though, and I appreciate there is a lot of chemistry in LSPs though I would argue a lot less chemistry in light, sight and perception.


I`m Sorry but I disagree with this, but this is from a personal point of view. 
I own a rover 200 BRM, which is Brooklands Green.
The colour is a very "flat Green", the only way I can Describe it, its a shade different to British Racing green. In shadow or out of direct sunlight it seems dark but when sunlight hits it , it can seem more washed out like a pastel shade of it.
I tried loads of different waxes and agree some made little or no difference, some a little shiny, some a little wetter looking, but not a lot of difference.
I bought a tub of P21s wax from someone on DW and tried that, the difference was amazing, it was a total transformation, the whole colour and look of the car changed.
The car looked glossier , sharper and the colour never seemed "washed out" looking in the sunlight, its actually hard to describe as its not just the shine but the whole thing, colour,shine etc it went from drab to alive.
Now you may say that its just what i perceived but everyone who saw the car commented on it, even people who pass walking their dogs make comments about how good the car looks, never happened with any of the others.
Think I was very lucky but i do think it can make a big difference but think its down to trial and error, or luck to find the right product for the job in hand.
This is a personal observation but i do think it accounts in part for the reason why one person can love a product and get excellent results whereas another finds the same product inferior.
Just my opinion anyway
:thumb::thumb:


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## Clark @ PB (Mar 1, 2006)

Dodo Factory said:


> There are only going to be two ways an LSP can enhance a clearcoat finish... surface characteristics and depth.
> 
> If the surface of the LSP allows for a more microscopically smooth surface (because even glass is pitted when examined under a microscope) and the LSP can fill in the small pores and indents within the clearcoat surface (for it will be attacked and pitted by UV light, stones whatever) then it will reflect light better. It may only need a micron to do this. That is why filling agents can work... they fill in a micron deep swirlmark and improve the optics of the surface.
> 
> ...


Good post :thumb:


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## hotwaxxx (Jul 12, 2007)

Clark said:


> Cheers mate, cheques in the post
> 
> It might be worth taking a look at our FAQ section if you havent already done so as this expresses our views on what other products suit certain colours just in case that maybe helps make your mind up about product choice especially for solids/mid tones etc  :
> 
> ...


Cheers Clark. I may just have to buy some Werkstat Acrylic now following that appraisal.


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## Clark @ PB (Mar 1, 2006)

hotwaxxx said:


> Cheers Clark. I may just have to buy some Werkstat Acrylic now following that appraisal.


Its product of choice on my Car too :thumb:

http://www.detailingworld.co.uk/forum/showthread.php?t=77348


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## Dave KG (Feb 23, 2006)

dantheman said:


> I`m Sorry but I disagree with this, but this is from a personal point of view.
> I own a rover 200 BRM, which is Brooklands Green.
> The colour is a very "flat Green", the only way I can Describe it, its a shade different to British Racing green. In shadow or out of direct sunlight it seems dark but when sunlight hits it , it can seem more washed out like a pastel shade of it.
> I tried loads of different waxes and agree some made little or no difference, some a little shiny, some a little wetter looking, but not a lot of difference.
> ...


That is quite interesting, and I do not debate your observations and am happy you have seen a differnece... but as you have also commented, many others find P21S inferior in the looks department - so who is right? Or is it rather a phychological effect, which is why different people see different things? Based on my own testing, I would have to say (again, in my personal opinion) that it is more the latter than the former (wax offering big additional looks).

This is of course of perfectly prepped paint, by machine polishing.

What is the prep carried out on your car before hand? As Dom above points out, if the prep is not spot on, then waxes can achieve a slight filling which will improve the looks...


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## Clark @ PB (Mar 1, 2006)

I always found P21S to be pretty decent in terms of looks, it was one of the first waxes i bought years ago - however durability was approximately 2 or 3 minutes :lol:


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## hotwaxxx (Jul 12, 2007)

Clark said:


> I always found P21S to be pretty decent in terms of looks, it was one of the first waxes i bought years ago - however durability was approximately 2 or 3 minutes :lol:


I know you use Werkstat Acrylic on your WR1 (you have something like 8 billion layers on I think).

Totally agree with P21S - this wax gives an unbelievable finish and dare I say it, looks-wise is about the best wax around for me. Durability is the only issue that stops this wax being about the best there is.


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## Incubus (Jul 16, 2007)

looks like I opened a can of worms here!

Looks like I'll just have to direct him to this thread 

personally I believe what I see rather than what I read and can definitely see a big difference between my (prepped) paint with 0 layers of werkstat and my car with 5 layers of werkstat, but I guess it's all subjective


yea Clark, Scott L from Bervie


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## Clark @ PB (Mar 1, 2006)

Incubus said:


> looks like I opened a can of worms here!
> 
> Looks like I'll just have to direct him to this thread
> 
> ...


Ha ha no way, I figured it might have been you from the Incubus name and the private plate on your polo - long time no see!


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## dantheman (Dec 10, 2007)

the car had been bought as an insurance write off (wing, bonnet, bumper)
it was repaired painted and stood in the garage for a good six monthe before I got round to having it prepped. 
It was fully machine polished before hand, as I intend to keep the car, its one of only 795 UK cars.

I had a mondeo estate as well, a purple blue colour, thought great p21s straight on going to look good, not at all , did very little, nothing different to any other wax

I personally think there are to many variables involved to say yes use this on this car or colour for an amazing finish.
Even down to the clearcoat exposure to sunlight, temp etc in its lifetime.
I think trying to find the perfect product for a car is like searching for the holy grail, but I think you can find things that work wether by luck or trial and error.
I think everybody will agree that at some point they have seen a car or done a car with a finish so good that it stands out from the rest and i think this is where everything has come together,right product for the job, its got the wow factor.

But I think as you stated, realistically its down to finding a product which you perceive as giving the most consistent and eye pleasing finish

but at the end of the day it all comes down to what looks the best
:lol::lol::lol:


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## perm (Oct 26, 2005)

The answer is very simple.... IMHO
On well prepared paint which is flawless then a wax / sealant will not make a difference to the looks of the paint surface. ( well at best a very subtle difference )

On a non flawless paint finish, different products will make a noticeable difference to the way the paint looks.


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## akimel (Oct 25, 2008)

perm said:


> The answer is very simple.... IMHO
> On well prepared paint which is flawless then a wax / sealant will not make a difference to the looks of the paint surface. ( well at best a very subtle difference ) On a non flawless paint finish, different products will make a noticeable difference to the way the paint looks.


Thank goodness they do, therefore, as I am unlikely ever to polish my paint surface to *non-flawless* condition. I need all the help I can get!


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## RaskyR1 (Jan 6, 2009)

I'm still on the fence over this one. I will agree that the differences are minimal on a well prepped panel though. I've actually found that it seems to depend on the light. I held a training day at my shop last summer, and I had polished out an old black hood to do some wax comparisons on. I had taped off 6 sections and applied a different wax on each panel. I set the hood out in direct sunlight for people to see when they arrived. They were to vote on which section they thought looked best. In the early morning hours, 3 waxes stood out as having a darker look to them. By mid day with full sun over head, *no* difference could be seen. Come late afternoon, the darker 3 started to stand out again.

Cheers,
Rasky


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## akimel (Oct 25, 2008)

One often hears about specific waxes darkening paint, doesn't one? There seems, e.g., to be a consensus of opinion over at MOL that M26 darkens the paint, whereas M16 leaves a brighter look. Is this mere fantasy on their part? What would motivate the fantasy? I can understand persuading myself to believe that Best of Show looks better on my Luthien than does, say, P21S--how else to justify the investment?--but why would I persuade myself that two comparably priced waxes from the same company produce two different looks? 

Perhaps it does come down to psychology, but the problem is that the psychological explanation can also be employed to undermine the position that waxes do not really add anything. I might well persuade myself that I cannot see any difference between two waxes precisely because I am personally committed to, or at least leaning toward, the view that polishing preparation contributes 100% to paint appearance. 

Unfortunately, I do not know of any way to negotiate this thicket. We are captive to the hermeneutics of suspicion. Blind testings, such as the one Dave ran last year, do provide crucial evidence; but I think that evidence from multiple blind tests would need to be offered before we could say that either position has been probatively established. One test is suggestive, but there are two many variables to claim that it is anything more than that. IMHO, of course. 

Cheers,
Al


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## Guest (Feb 10, 2009)

Great argument akimel....

20 years ago, was a about the time of a changeover to clear-coats. The end all to LSP's. And you didn't seem to have over 500+ soft/hard/liquid products to choose from back then either. Now you get the boutique waxes from both small and large house's. To add to that is marketing and perceptions.. Than top it all off with sites like this where you learn more about different products and suddenly, what you have just seems inadequate and you know just around the corner is that magical one you will buy for the last time, til you read once again that what you seem to have is coming up short again.


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## Clark @ PB (Mar 1, 2006)

What I would like to add into this is that personally I've never found side by side comparisons to work for me, I.e. a panel taped into x amount of sections with different LSP's applied to each section. The whole car needs to be done to fully appreciate the final result in my opinion


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## RaskyR1 (Jan 6, 2009)

Clark said:


> What I would like to add into this is that personally I've never found side by side comparisons to work for me, I.e. a panel taped into x amount of sections with different LSP's applied to each section. The whole car needs to be done to fully appreciate the final result in my opinion


While I do agree with you on this, the difference in the darkening between panels was very visible, and all 15-20 people who attended noticed it. 

It can even be seen in the pics......please ingnore the finger prints on the paint. :wall:

I would also add that this hood was damaged and from a body shop. I did run over it with M105 and finished off with Menz Nono polish in the testing area, but there were some RIDS that remained.


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## Bilt-Hamber Lab (Apr 11, 2008)

RaskyR1 said:


> While I do agree with you on this, the difference in the darkening between panels was very visible, and all 15-20 people who attended noticed it.
> 
> It can even be seen in the pics......please ingnore the finger prints on the paint. :wall:
> 
> I would also add that this hood was damaged and from a body shop. I did run over it with M105 and finished off with Menz Nono polish in the testing area, but there were some RIDS that remained.


:thumb:This is a very good post. Only when the light and all other variables are the same for each product at the same time can a true assessment be made. We conduct or own testing in exactly the same way. However I do agree than 6 vehicles all treated with different products would be hard to differentiate.

Wax / polish film are only around 0.002microns, but they can be made to behave in quite unique ways, the depth, or wet look, they impart, and which these photo's show, can be measured very accurately in the lab using a Spectrophotometer, and a 20 degree angle for gloss meter reading is a valid too.

We also test detergent resistance and slip.


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## akimel (Oct 25, 2008)

RaskyR1 said:


>


I keep looking at the two photos and wondering, "Okay, which ones are the darker ones?" What can I say? I'm an absolute dolt! :lol:


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## dantheman (Dec 10, 2007)

I`ve been sitting thinking about this and on reading DaveKG`s first post on the subject, I believe here lies the proof that a layer of wax/sealent does work
if you look at it in sections, each one answers the questions

"How do you see what you see? Light enterring your eye. So, you see red paint because white light reflects off the paint and the paint absorbs all colours and reflects red and you then see the red (in a simple sense). Now, adding a submicron layer of a "clear" film to the paint finish introduces another boundary of different refective index"

Adding a layer of wax creates a new surface or layer which light will pass through but some will also be reflected straight from the surface, a bit like taking a picture in a darkened garage with a floodlight set at an angle, the light reflects off giving a really glossy appearance
This is where the effect of a warmer glow from a wax a hard/sharper from a sealent, basically the different appearance of different products depends how sharp or diffused the reflection.

"... so the light goes from air, through the wax layer, through the clearcoat layer, bounces, and returns through these layers... Each layer will change the light as it travels through it by altering its direction, and its wavelength... Typical light wavelength in air is around 400 - 700nm (0.4um to 0.7um). Is this of the order of the thickness of an LSP layer? I suspect the thickness is of the order of the wavelength in the wax medium and from this one would suspect that you can get multiple reflections from boundaries interfering constructively to give an enhanced reflection. "

this could be why some waxes are supposed to improve the appearance of the flake, by the light getting bounced around it, which hit the flake from different angles giving the appearance of flake popping, plus add this effect to a darker background as described below

"However, if this indeed does happen you will reduce the light to the colour coat and take away from the colour intensity (which we know does not happen to a tenable level). Further, this effect will rely on even layers - and the paint is not even and neither will the LSP layer."

But if it does reduce the amount of light or intensity this would result in the paint appearing darker or deeping, which is what a lot of people describe, dark colours becoming deeper and richer

dont dispute that a properly prepped surface is a must but do believe that a wax or sealent is the icing on the cake


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## FinstP (Nov 29, 2008)

This is an interesting thread to me, and one of the reasons that I joined this forum. I run a thin film centre specialising in the design and manufacture of optical filters, which are made from multiple layers of totally transparent films but which can be used to produce anything from 0% to 100% reflectance depending on the number of layers, their refractive indices and thicknesses. These filters are rarely more than a few microns in total thickness. We also have the equipment to accurately measure reflectance over the visible ange of wavelengths at all angles. If anyone wants to send smallish flat samples of "before and after" waxes/finishes then i am interested enough to measure them. We can measure sub-nanometer thicknesses in principle.


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## Dave KG (Feb 23, 2006)

dantheman said:


> I`ve been sitting thinking about this and on reading DaveKG`s first post on the subject, I believe here lies the proof that a layer of wax/sealent does work
> if you look at it in sections, each one answers the questions
> 
> "How do you see what you see? Light enterring your eye. So, you see red paint because white light reflects off the paint and the paint absorbs all colours and reflects red and you then see the red (in a simple sense). Now, adding a submicron layer of a "clear" film to the paint finish introduces another boundary of different refective index"
> ...


But from a purely ray optics analysis of the light model, 0.002um thickness is sub-wavelength and thus the effects you describe here would not be replicated in practice... Naturally the ray optics description is over simplified, but its basis backs up the experimental evidence from the wax test rather well. 

I suggested the above as examples as to what could cause changed in appearance but alas I am not convinced they apply to a wax layer - certainly not when analysed from a simplistic model, but perhaps a more advanced model of the light behaviour will allow one to account for certain effects. If the layer was much thicker, not sub-wavelength, then I would happily say the effects you describe do make a difference - some claim that thicker lacquer coats look glossier for example and this is explained by what you have outlined above.

When I am not shattered after a hard day in the lab I will break the analysis down and run a few numbers and test a couple of simplistic theoretical models and see what I come up with - not saying they will be correct, but I'm yet to read a convincing scientific argument so I'll see if I can make one myself


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## Dave KG (Feb 23, 2006)

Clark said:


> What I would like to add into this is that personally I've never found side by side comparisons to work for me, I.e. a panel taped into x amount of sections with different LSP's applied to each section. The whole car needs to be done to fully appreciate the final result in my opinion


Exactly, and something I believe too, which is why the wax test used 7 full cars rather than just panels for the comparison.


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## Clark @ PB (Mar 1, 2006)

Dave KG said:


> Exactly, and something I believe too, which is why the wax test used 7 full cars rather than just panels for the comparison.


I assume the cars weren't all prepped by the same person?


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## dantheman (Dec 10, 2007)

finding this really interesting
:thumb::thumb::thumb:


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## FinstP (Nov 29, 2008)

One of the difficulties in any such discussion is the subjective terminology used by people to describe observed effects. People, even specialists, will probably always struggle to come up with terms that make sense of our senses! Try explaining how something new tastes or smells to someone without resorting to; it tastes like ...., or it smells like .....

Actually, optics probably goes quite far in allowing objective descriptions of basic visual appearance, but there is still a long way to go, as can be seen from this thread. Scientific terms like reflectance have definitions that should make them mean the same thing to everybody (if they were to actually read the definition!) and these definitions generally also allow quantitative measurements to be made on suitable, well-defined instruments.

Ignoring lasers, fluorescence and other exotic non-linear effects, what happens to light striking a coating is relatively straightforward to describe scientifically. 
Some of the light is reflected, some is transmitted, some is absorbed and some is scattered, that's all that can happen. 
The total intensity is conserved (you can account for all of the incident light in terms of these four components). There are good, sound scientific theories that can calculate the fraction of the incident light that ends up being reflected, etc (but then you need to study physics to understand what material properties are important, and crucially, what simplifying assumptions are made). 
Good science goes a long way to explaining what is measured by scientific instruments, but "appearance", which means how something looks to a human being, is something else altogether. 
For example something that is truly "black" ought to absorb all light that falls on it and therefore should not reflect, transmit or scatter any light at all. 
Real materials can come close to this ideal only over a limited range of wavelengths and a limited range of angles of incidence of the light. At low angles of incidence, all black paints tend towards 100% reflectance! Most will also become transparent at some range of wavelengths (but not necessarily those that can be seen by the human eye). A description of "black" therefore needs to include how much light is reflected and scattered. The engineering term "Gloss" is intended to capture this idea and is a reasonably well defined, measurable, term, but is not a perfect description of how a coating will actually look under real lighting conditions on non-flat panels. This shouldn't stop people from trying to find better, meaningful decriptions!

That's enough for this post, I could continue, and will if anyone's interested. Meanwhile, although my offer in the previous post holds, I don't suppose it's too practical unless people are prepared to cut up panels. Maybe best if I make up some test pieces myself and report back on the results.


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## Bilt-Hamber Lab (Apr 11, 2008)

Dave KG said:


> Exactly, and something I believe too, which is why the wax test used 7 full cars rather than just panels for the comparison.


But weren't the comparisons subjective? Different cars parked in different spots, under constantly changing light conditions with each observer's eyes at different heights? You reduce the influence of at least some of these if you test in non-lab conditions by using the same panel. You're looking a very minor and subtle differences, but they are there - you can measure them.

This is why controlled measurement using the equipment referred to in my earlier post such as, inter alia, a Spectrophotometer with Specular Excluded produces reliable comparisons


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## Dave KG (Feb 23, 2006)

Clark said:


> I assume the cars weren't all prepped by the same person?


The same people did the same sections on each car to ensure consistency, this was well thought out during the test. 



Bilt-Hamber Lab said:


> But weren't the comparisons subjective? Different cars parked in different spots, under constantly changing light conditions with each observer's eyes at different heights? You reduce the influence of at least some of these if you test in non-lab conditions by using the same panel. You're looking a very minor and subtle differences, but they are there - you can measure them.
> 
> This is why controlled measurement using the equipment referred to in my earlier post such as, inter alia, a Spectrophotometer with Specular Excluded produces reliable comparisons


Again, we were clever in the way data was taken - yes, subjective comparisons. But, the cars were moved around to ensure a random nature to the viewing of the cars and this will have nulled the different spots issue to allude to. Naturally each observer has different heights, but now we reach the realms of a group of people, all with a different eye, not being able to (collectively as a group) see a tenable difference between the finishes.

While this test is not as accurate as putting a calibrated instrument on the panel, it answers the question of: "is their a perceivable difference to the human eye?". The test conclusively shows that for that particular sample, the answer is no. And this is backed up by much other anecdotal evidence.

I would be very keen to see the results you are seeing from the spectrophotometer published so we can analyse and compare the results, similarly to the wax test as they would be valuable and help to add value to the debate... if you would be so kind as to publish some data for us? However, one should be very careful with using high accuracy instruments and its a trap many people in science fall into - yes, we can tell apart a very tiny difference but in real world terms, what does this actually mean? Can we as humans perceive a difference? Which of course is the important factor to measure here, and one should be careful not to use a sledgehammer to crack a nut so to speak. But from a purely academic point of view, which is of interest to me, I'd very much like to see results published and an analysis of them 

Again, from a purely academic point of view, I wonder if you can give some information on the instrument itself and how it works, and what exactly it is measuring, physically? And how it achieves this measurement and what comparisons can be inferred from the data? I'm interested to know these things, again from the inquisitive scientist point of view, and also to allow myself to best analyse any data I see published from the instrument.


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## Dave KG (Feb 23, 2006)

A fellow physicist?



FinstP said:


> One of the difficulties in any such discussion is the subjective terminology used by people to describe observed effects. People, even specialists, will probably always struggle to come up with terms that make sense of our senses! Try explaining how something new tastes or smells to someone without resorting to; it tastes like ...., or it smells like .....
> 
> Meauring human perception is never an easy thing to do, and ultimately it is a job not for a physicist or chemist, but in many ways a physchologist - there are many "real" effects that we can perceive but then all of our perceptions are different and then we have the "non-real" effects which are just the brain playing tricks on us - which can be affected by what we are told, and what we believe as outlined above.
> 
> ...


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## Rich @ PB (Oct 26, 2005)

A lot of interesting thoughts above, and maybe a question that will never be answered fully due to the fundamental underlying issues, i.e. do we all see in the same way? Here is a side by side I posted up years ago, and I can still see a small but definite difference in the two finishes; in the flesh, Werkstat gives a sharper, darker look with greater flake pop on WR Blue, whereas the Blackfire gives a glossier, richer look with less clarity and flake pop. In the images, this can be seen if you look carefully enough (particularly at the sky in the door shots), but of course, monitors cary a lot in terms of the image they present, so I can accept that some people will see no difference. I can though!

http://www.detailingworld.co.uk/forum/showthread.php?t=5818


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## Rich (Oct 26, 2005)

I remember that thread, pictures can't easily be used - only way to show the two differences in the cars would have be to have a panel of each car in the same shot - As the exposure on say the door shots will be slightly different in each picture anyway.

I can notice the nuances in waxes and sealants on my own car though so can easily believe in the flesh you would see the difference.

I remember putting Mseal on my old Black clio and it looking all washed out on grey, changing to Werksatt and noticing how rich and black it looked.


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## dantheman (Dec 10, 2007)

been having a look at the original post on the seven cars
cannot find the ranking for the unwaxed car
can someone tell me the position it came in the rankings
:thumb:


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## Dave KG (Feb 23, 2006)

dantheman said:


> been having a look at the original post on the seven cars
> cannot find the ranking for the unwaxed car
> can someone tell me the position it came in the rankings
> :thumb:


It was only viewed later in the day as we had some problems with the paint on the car - Harely will be able to explain the full details of it, as he worked like a trojan horse on the day of the viewings to get the car sorted and out!


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## dantheman (Dec 10, 2007)

were the votes taken on points given for a 1st 2nd 3rd etc
or am i looking at the wrong results


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## Dave KG (Feb 23, 2006)

dantheman said:


> were the votes taken on points given for a 1st 2nd 3rd etc
> or am i looking at the wrong results


There's a full explanation of the results and the way they were achieved in the threads (stickied, top of this subforum)... essnetially, people ranked what they felt was the best car and they were awarded points based on this, which were the summed to give an end result... though as you will see from my analysis of these results, one would not infer exact positions from these especially as looking at the results (fully outlined) there is nothing more than what could be attributed to statistical variation.

Further to the 7th car, looking through my own files on that, the car was dealer prepped (the only one of the 7), and whatever was used resulted in sticky paint and trouble with the correction which caused it to run into the day of the test itself...


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## dantheman (Dec 10, 2007)

:thumb:


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## Bilt-Hamber Lab (Apr 11, 2008)

Dave KG said:


> The same people did the same sections on each car to ensure consistency, this was well thought out during the test.
> 
> Again, we were clever in the way data was taken - yes, subjective comparisons. But, the cars were moved around to ensure a random nature to the viewing of the cars and this will have nulled the different spots issue to allude to. Naturally each observer has different heights, but now we reach the realms of a group of people, all with a different eye, not being able to (collectively as a group) see a tenable difference between the finishes.
> 
> ...


Dave - Hunter make some great equipment and describe the process here http://www.hunterlab.com/pdf/color.pdf

My point is that only my careful measurement can a manufacturer judge the relative performance of its own products, or how they compare with others and indeed how formulation changes improve the products.

We will be adding test data to our site in due course, any comparisons with other manufacturer's products will be data produced by a third party.

I can say with certainty that when applied side-by-side on the same test panel the human eye can see a difference in the "jetting" imparted by different products, though this difference is indeed (in most cases) only small.


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## drive 'n' shine (Apr 22, 2006)

God I wish I was an egg head, most of this thread just read as blah blah blah to me :lol:

Anyway you guys to say all that ^^ in word of less than 2 syllables so a simpleton like me can understand it


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## FinstP (Nov 29, 2008)

Dave,

There is a multi-billion dollar industry based on paints/coatings. There is not much that has not been done! The post from Bilt-Hamber (http://www.hunterlab.com/pdf/color.pdf) is a good start if you want to start to catch up - and this is very out-of-date, not covering fluorescent paints or colour-shift paints that change colour with viewing angle. All this work has been designed to take take into account the differences between observers, so we can predict what the average person should see from precise scientific measurements.
It is easy to demonstrate that the human eye can discern reflectivity changes of less than 1 % in some circumstances - if you have AR coated specs, just touch the surface with your finger - you will easily be able to detect the area you touched).
The perception of colour is very much the domain of physicists - given your interests, it seems you chose the wrong university in Scotland in which to do your PhD!
You don't have to go back to Maxwell's equations to derive the appropriate equations, it was done 70 years ago. In fact, if you have MathCad then you can download a worksheet of mine that allows you to calculate R, T and A for arbitrary numbers of layers at arbitrary angles of incidence for materials with complex refrective indices (search for multilyrs.mcd on Adept Scientific's site). 
The Hunter Lab equipment is very good but is designed for routine measurements. We have state of the art equipment (ellipsometers and spectrophotometers) along with software thet can extract the thickness and complex refractive index (squareroot of dielectric constant, and more commonly used in the visible range) for films of thicknesses less than one nanometre.


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## Dave KG (Feb 23, 2006)

FinstP said:


> Dave,
> 
> There is a multi-billion dollar industry based on paints/coatings. There is not much that has not been done! The post from Bilt-Hamber (http://www.hunterlab.com/pdf/color.pdf) is a good start if you want to start to catch up - and this is very out-of-date, not covering fluorescent paints or colour-shift paints that change colour with viewing angle. All this work has been designed to take take into account the differences between observers, so we can predict what the average person should see from precise scientific measurements.
> It is easy to demonstrate that the human eye can discern reflectivity changes of less than 1 % in some circumstances - if you have AR coated specs, just touch the surface with your finger - you will easily be able to detect the area you touched).
> ...


Not that its much to do with the thread, but I would naturally strongly disagree with this statement and hope that its tongue in cheek! My research area is Electron Spin Resonance, so quite far removed for the analysis of light (other than a bit of microwave engineering which I dabble with as I build my own ESR spectrometer) in the world of magnetic resonance but I can still use my Physics knowledge that I have from general areas as well to solve problems with which I am faced... like any good Physicist, I break down a problem into what I know and build up from there, and also like any good Physicist I like to go back over a derivation to increase my own understanding of it.

As you will no doubt appreciate, when one comes to a research area with which they are not familiar in depth (light, colour is not my area of expertise, my research is magnetic resonance), they can only base their thoughts on general knowledge and information I have from my own degree  ... I am currently slowly bringing myself up to speed on this area as well, quite far removed from my own, and in so doing it is my approach to derive as much as I can rather than rely solely on what has been done before me - just the way I am, I like to ensure I can understand fully before I build on it. Simply plugging numbers into a Mathcad model gives me answers, but it tells me nothing if that makes sense... I like to know _how_ a system works. I dont have to go back to Maxwell, someone has already done this for me - but you know, I would want to go back and derive it for myself, mainly here I imagine because I am doing so out of interest rather than out of it being my job where I _need_ results in a hurry 

Re: perception of colour, perhaps my post was misunderstood here. Naturally, colour and how the human eye sees it is very much in the domain of Physics... but what it also clear is that it is not _purely_ in the domain of physics and the human brain can "change" what different people see in ways that we simply cannot understand from equations like you use in your Mathcad sheet. There is a physchological element and one should not discount it. In a simple sense, why do we see red? Because a 663nm photon has hit out retina, its responded and a signal has been sent to the brain and the image they eye has produced is flipped so its right way up by the brain and we see it... I see a 663nm photon as red, so do you. But how do we know that red is the same to both of us? We don't - and this is what I was meaning above. Scientifically, we see the same photon and we both call it red, but there's not way of telling what I see as red is the same as what you see as red - its a little phschological mind game that one, and as scientists we typically hate playing them (part of the curse of your dance partner being a physchologist I imagine ).


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## Dave KG (Feb 23, 2006)

Bilt-Hamber Lab said:


> Dave - Hunter make some great equipment and describe the process here http://www.hunterlab.com/pdf/color.pdf
> 
> My point is that only my careful measurement can a manufacturer judge the relative performance of its own products, or how they compare with others and indeed how formulation changes improve the products.
> 
> ...


Thank you, I will have a read through the link when time allows 

I look forward to seeing test data, both by yourselves and that produced by a third party, and see how it compares with more experimental evidence "in the field" so to speak, of which the wax test is a very good example :thumb:


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## FinstP (Nov 29, 2008)

Dave KG said:


> Not that its much to do with the thread, but I would naturally strongly disagree with this statement and hope that its tongue in cheek! My research area is Electron Spin Resonance, so quite far removed for the analysis of light (other than a bit of microwave engineering which I dabble with as I build my own ESR spectrometer) in the world of magnetic resonance but I can still use my Physics knowledge that I have from general areas as well to solve problems with which I am faced... like any good Physicist, I break down a problem into what I know and build up from there, and also like any good Physicist I like to go back over a derivation to increase my own understanding of it.
> 
> As you will no doubt appreciate, when one comes to a research area with which they are not familiar in depth (light, colour is not my area of expertise, my research is magnetic resonance), they can only base their thoughts on general knowledge and information I have from my own degree  ... I am currently slowly bringing myself up to speed on this area as well, quite far removed from my own, and in so doing it is my approach to derive as much as I can rather than rely solely on what has been done before me - just the way I am, I like to ensure I can understand fully before I build on it. Simply plugging numbers into a Mathcad model gives me answers, but it tells me nothing if that makes sense... I like to know _how_ a system works. I dont have to go back to Maxwell, someone has already done this for me - but you know, I would want to go back and derive it for myself, mainly here I imagine because I am doing so out of interest rather than out of it being my job where I _need_ results in a hurry
> 
> Re: perception of colour, perhaps my post was misunderstood here. Naturally, colour and how the human eye sees it is very much in the domain of Physics... but what it also clear is that it is not _purely_ in the domain of physics and the human brain can "change" what different people see in ways that we simply cannot understand from equations like you use in your Mathcad sheet. There is a physchological element and one should not discount it. In a simple sense, why do we see red? Because a 663nm photon has hit out retina, its responded and a signal has been sent to the brain and the image they eye has produced is flipped so its right way up by the brain and we see it... I see a 663nm photon as red, so do you. But how do we know that red is the same to both of us? We don't - and this is what I was meaning above. Scientifically, we see the same photon and we both call it red, but there's not way of telling what I see as red is the same as what you see as red - its a little phschological mind game that one, and as scientists we typically hate playing them (part of the curse of your dance partner being a physchologist I imagine ).


Of course I was joking about the PhD. However my main point to you is that this is a well developed subject that has involved the efforts of huge numbers of well qualified people (just like ESR). Like any subject that is new to you, you should read something of what has been done before, because nobody has the time to start from scratch. From your comments I would think that you will be agreeably surprised at how much is understood about the human perception of "normal" colour and colour differences. I only say "normal" because there are some beautiful optical illusions that require a deeper insight into how the brain processes information. I would ask that you read the hunterlab color.pdf and then honestly tell me whether your knowledge has increased and by how much!


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