D.O.F. with a flash

[R.Robbins]

Is theyre a way other then manual mode to get decent dept of field with a Metz 54 flash on a EOS 30d. I use my camera to take shots of snakes and Lizards at night alot of the time to be logged into a national database but my problem is that In P mode it sets the aparture to f4 on my
70-200 f4 L Sometimes this is too shallow especially if it is a quick moving animal it moves and its eyes are out of focus If I could use a higher aparture I could get a larger plane of view to work with. Is theyre a way to set up Av mode or another mode that will get me a larger dept of field?

 

[EOS_JD]

Not 100% sure on this but this is my thoughts..... Someone may be able to confirm or correct what I'm saying here.

You need to get out of P mode as it sets SS to 1/60th with an appropriate aperture value. It uses the flash as the main light generally.

In Av mode dial in the required aperture and the shutter speed will be selcted by the camera to expose for the background. this may mean a slow shutter speed. Now remember if you dial in a smaller aperture like f8, you'll need more flash power and the flash range will be cut a bit unless you compensate by upping the ISO.

Slower shutter should not matter too much regards the subject as the brief burst should stop any motion.

If you use M you can also select a shutter speed but if you select a faster shutter speed than the background metering, the background will become darker although the subject should be exposed properly.

 

[Big Mike]

That's right, just use a smaller aperture to get a bigger DOF. As mentioned, this will make your flash have to work harder, which reduces your recycle time and your effective range.

 

[EOS_JD]

That's right, just use a smaller aperture to get a bigger DOF. As mentioned, this will make your flash have to work harder, which reduces your recycle time and your effective range.

And as I stated if you increase your ISO this will increase your recycle time and your effective range.

It's a decision only you can make. Do you want noisy images with a better exposed subject and background or a well exposed subject and darker background.

I saw a movie on the Canon 580EX/430EX flash unit the other week and it was fantastic! A friend had it and it really has helped me understand flash a lot more. I'm going to buy a couple of decent reflectors and try some still life and portraits using my 580EX and Sigma 500 super.

So far i've found flash difficult and although I can set it in ETTL and fire away with some success I'm happy that i might be able to understand it a bit more now.

 

[Big Mike]

Where did you see this movie? You have perked my curiosity.

 

[EOS_JD]

If memory serves me right it was a Blue Crane video. In fact I just did a search and found it

[ame]http://www.amazon.com/Canon-Speedlite-580EX-Tutorial-Digital/dp/B000E46XB2/ref=pd_bbs_sr_3/103-4776952-7438253?ie=UTF8&s=books&qid=1175729076&sr=8-3[/ame]

I think it was sent to the UK by my friend's family member who lives in the US. I'd never heard of them before but might see if I can order the 20D one from Ian Kerr (an ebay seller who imports to the UK and lives in the US).