# Getting more of a photo in focus?



## minimadgriff (Jul 8, 2007)

Evening chaps, 

hopefully I will make sense here. How do you get more of a photo in focus? some times when I take a pic not all of the object i am photographing is in focus? or if I want the main object and back ground in focus only one is? Is this Depth of field? 

Any Ideas what I need to do? 

Thanks 

Ben 

(Sony A350 with 18-200mm lense)


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## SBerlyn (Nov 9, 2008)

You need a larger depth of field; that is a smaller aperture (but bigger number  )

So for instance, F22 will give you larger DoF than F4

Try aperture priority mode as this will still automate the exposure for you based on the aperture you select 

S


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## minimadgriff (Jul 8, 2007)

thanks for the tips. 

doesn't changing rhe F number make the shutter stay open longer, so more chance of camera shake/blurr?


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## wookey (Jul 13, 2007)

Having a smaller aperture (larger f stop i.e f22) means you need a slower shutter speed.

Basically the diameter is smaller so less light gets through, which means you need a slower shutter speed to allow the light to come through the smaller diameter.

*edit*

check out the wikipedia link, it makes more sense with pictures lol

http://en.wikipedia.org/wiki/Aperture


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## beardboy (Feb 12, 2006)

The shutter speed makes the shutter stay open longer, the ISO controls the brightness and F is the aperture (DoF) as above.

If you have an ISO of 1600, the image will be VERY bright in daylight, but very fuzzy at night.

That's my understanding anyway, but i'm no pro, just fiddle with my DSLR every noe and then :lol:


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## bretti_kivi (Apr 22, 2008)

> doesn't changing rhe F number make the shutter stay open longer, so more chance of camera shake/blurr?


yes, depending. If we're talking about the difference between 1/200 and 1/500, I don't think you'll see the additional shake.

You are talking about Depth of field (DoF).

Higher DoF - so more in focus - depends on the lens (longer lenses mean lower DoF) and the distances involved.

If you're talking about a flower, 2" away, your DoF is always going to be minimal. Using a 10mm lens would help, but still not remove the issue.
If you're talking about a car on the other side of the road, then the DoF should be changeable. f32 will see most of it in focus, f2.8 just the part of the mirror. But f2.8 also may mean "too much light" and therefore you might not be able to take the shot (1/2000 may still be too slow!) - without resorting to ND filters. (Neutral Density - like buckas uses for his sunsets, but with the whole filter dark).

ISO can help you to vary towards the settings you want. Remember that you might *want* specific shutter speeds - say 1/125 for some motorsport stuff in bright sunlight - but above f/16 your lens might not be so hot, so you drop to ISO100. Adding an ND might then give you what you want / need.

Make sense?

Bret


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## PaulGTI (Oct 21, 2006)

This dude seems to explain it well, he has other vids worth watching too...


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## VixMix (May 8, 2008)

http://stopshootingauto.com/

A good blog with a excellent bit on DOF and exercises for you to try


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## minimadgriff (Jul 8, 2007)

thanks for all the replys, it's very much appreciated. It really helped with a shot I had to take yesterday!


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## slim_boy_fat (Jun 23, 2006)

minimadgriff said:


> thanks for all the replys, it's very much appreciated. It really helped with a shot I had to take yesterday!


Going to share......?


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## minimadgriff (Jul 8, 2007)

slim_boy_fat said:


> Going to share......?


nothing too special really, just the shot that is being used on a banner at autosport and in the mags :thumb:


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## bretti_kivi (Apr 22, 2008)

good job.

Bret


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## stink (Nov 19, 2008)

nice shot  looks liek a bit of a track beast!


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## minimadgriff (Jul 8, 2007)

stink said:


> nice shot  looks liek a bit of a track beast!


Cheers :thumb:

Track beast? Its our new BTCC car  Just waiting on a new aero package for it.


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