F/Stop for Birds in Flight?

[KHarmon]

I know there are a lot of bird photographers here and I'm curious to know what F/stop you use when you shoot birds in flight?

I have been shooting at the fastest possible stop but is it wise to go with a stop that gives you more DOF and increases the opportunity to possibly get more of the bird in focus from wing tip to wing tip?

KHarmon

[Saorsa]

I start wide open and check the shutter speed. If I think it's adequate I will stop down a bit. In the case of this shot, I used f8 because I knew the action would be somewhere around the osprey but couldn't be sure where.



I still managed to get the shutter speed at 1/1250. If it droped much below 1/1000 I would have opened up a bit.

[Bobobird]

It is hard to put a hard and fast rule to that. I depends on the bird's features and does not mean just flight.

I will use 2 examples to illustrate.

Lets say you have a Great Blue Heron in just the right spot, exactly on the same plane as your camera. Typically you will focus on the eye and get a few shots. Say you are using f5.6. When you get home you find that the eye is indeed very very sharp but because the eye is protruding from the head the feathers just behind the eye are slightly soft. To get both sharp, you will want f8 or tighter so that the DOF covers the very front of the eyeball all the way back to the beak area.

Example 2 - an owl. Some like a Great Gray will have eyes that are recessed into the head and the face area is like a cup. Focusing on the eye, you will find that the entire front area including the beak are slightly soft. Then again you will want a tighter aperture to capture the entire depth of the head.

Same applies to in fight but because they are a bit further away the slight oof is not that perceptible but is there.

So as a general rule I will start with f8 or tighter if light is good. I do open up especially if the background is too messy and you want it creamed out.

[Brev00]

I think a lot depends on your lens. Wide open can be anything from 2.8 to 6.3 depending on the speed of the lens. Some lenses do so much better stopped down 1 stop which can mean, for slow lenses, you are automatically at f 8. Other lenses are pretty close to full sharpness wide open--at least adequately sharp for the job. It might also depend on your distance from the bird. If you are very close, the dof can be limited. At a greater distance, it might not matter as much. I know one bird photographer using an f 4 lens shoots at f 4 to maximize the shutter speed even if there is some aspect of the bird out of focus. But, that lens is pretty spectacular wide open. So, I think it is a combination of the strengths and weakness of the lens you are using along with the conditions at hand. My 70-300 is a slow lens but it is good at 300mm wide open. Unless the light is very strong, that is pretty much where I will be. I don't consider dof too much since if I can get a decent focus on the eye or head, all is good.