Hello, Padmoo! Welcome to our wonderful forum! It's nice to have you with us.
padmoo wrote in post #18313970
I'm thinking about setting it to Tv to freeze the birds in motion and raise the ISO to 800.
I will tell you what I would do if shooting birds with a 40D. What works best for you may be different, but I have good reasons for shooting the way I do and will share them with you.
I would mostly shoot in Av mode, a.k.a. Aperture Priority.
I would set the ISO to 400 and leave it there. Noise is a horrible thing to see in bird photographs.
I would give the exposure as much light as I could, without blowing out the highlights. I figure out what this exposure will be by shooting a test image, then looking at it on the LCD playback screen. Make sure that the blinkies are enabled. Increase the exposure of the test images until some blinkies appear, then back off 1/3 of a stop. The reason for this is that light is the enemy of noise, so if you give an exposure as much light as possible, you will be keeping the noise at a minimum.
For situations in which you do not have time for the above "test image method", I would have it on Av mode, set it to the largest aperture (lowest aperture number), and then dial in +2/3 of a stop exposure compensation. This is a good "catch all" that will give you the most chance of success when you don't have time to do fine-tuned exposure adjustments. But please do add the exposure compensation - the 40D, like other Canon DSLRs, seems to always underestimate the amount of light that is needed for a proper exposure. In other words, do NOT trust the 40D light meter. In fact, you may find that in many situations, adding a full stop of exposure compensation may be better than adding just 2/3 of a stop.
So basically what I am trying to do is to shoot an image that is brighter than what I want it to be, and then pulling the brightness down when I edit the photo on my computer. Doing this will result in the least noise and the fullest, richest colour gamut.
I would not worry about shutter speed unless the birds are flying or engaging in some type of fast, erratic behavior, such as fighting with one another. For most images, the birds will be still, and you can shoot great portraits at very slow shutter speeds. Many, many bird photographers mistakenly think that they need a lot of shutter speed, and this thinking usually keeps them from getting technically excellent photos in low light conditions.
As for White Balance, I would either use the auto WB setting or the "K" setting. When using "K", shoot a test shot at any temperature, then compare the image on the LCD with the scene in front of you. Make it warmer or cooler as needed to match the scene. Sometimes you may have creative reasons for not matching the actual scene in front of you, and the "K" setting is great for this, as it allows a great latitude of adjustment in either direction.
In giving you advice as to settings for the 40D, it would really help if we knew what lens you were using, and how frequently you use a tripod. I can't really offer any good advice about stopping down for sharpness unless I know what lenses you use for birds.
All of my above suggestions are based on my personal philosophy about bird photography, which is that I want excellent images. I do not really care about "getting the shot" unless the shot can be technically excellent.
What good is a photo if that photo has noise grain in it? What good is a photo if the background isn't perfectly rendered? What good is a photo if some of the highlights are blown? What good is a photo if some of the feather detail won't come up because the image is underexposed?
This is my thinking - that if conditions won't allow me to get a really good photo, then I don't want any photo at all. In other words, if I have to bring the ISO up to 800 (on a 40D), then why bother taking a photo at all? In that case I will just put the camera down an enjoy bird watching.
The way you feel about bird photography may be very different. You may want to take some photos even if they cannot be technically excellent, because you want to have a photo by which to remember your encounter. That is fine, and if that is the case then by all means push that ISO up to whatever you need in order to "get the shot".
This is why I cannot tell you what settings will be best for you. All I can do is to tell you what I would do if I were shooting birds with a Canon 40D.
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