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Iain Barker
08-21-2013, 07:28 AM
Hi

Does any have any tips or know of any good articles on manual metering for birds in flight?
I tend to use Av mode with +/- exposure compensation to get the correct exposure but always have a problem with the subject moving from the bright sky to being in front of the background trees etc.
I am looking for information on the best way to meter for the bird no matter what the background is then I will not need to keep altering the compensation while tracking the bird.

Thanks,
Iain

Daniel Cadieux
08-21-2013, 08:13 AM
Iain, if the light is constant on the subject then manual mode is the way to go. Determine your correct exposure before the action occurs, and then leave it on manual. Like magic the bird will remain properly exposed no matter what the background is behind it as it flies by. Much simpler than using AV for this type of photography.

Loi Nguyen
08-21-2013, 08:58 AM
Ian, to elaborate Daniel's comments further, you will need to determine the correct exposure for the particular species you are after before the actions occur. A white bird will require a different setting tan a black bird for example. Blue sky is often a good way to determine the initial exposure. Aim your lens to a patch of blue sky to determine the exposure. For white birds I would add about 2/3 EV. For dark birds like Red Tailed Hawk 1 1/3 EV. When blue sky is not present, you need to find some other sources to determine the exposure. Then adjust accordingly. You do need to re adjust the settings in early morning or late afternoon due to the rapid changing of the light. This is how I do it. Loi

David Stephens
08-21-2013, 09:48 AM
For BIF using Av mode will require adjusting to the BG behind the bird. For clear blue sky, Av with a +-EV adjustment (depending on the birds' color) will work nicely, Do a test shot to see if your EV adjustment is correct and then you can stick with that. Broken clouds are a different matter and Av will prove unreliable as a bird moves from blue sky, to white cloud edges to dark cloud undersides. This is a situation that demands a manual setting that won't be influenced by what's happening with the BG. Thanks to your preview screen, you can take test shots and adjust to taste.

I always find it intriguing to shoot manual mode and watch the EV reading spinning wildly up and down as you move past changing BG. I use Av mode plus EV adjustment, most of the time, but there are times when it's very unreliable and Manual is the way to go.

Markus Jais
08-21-2013, 03:34 PM
I agree with Daniel and Loi here. Manual mode is the way to go.
An example:

When I photograph gulls I set what I think will do in manual mode on my 7D/1DX, do a test shot and check the display/histogram. This can be a really crappy shot, as long as the gull is correctly exposed. If not I correct the exposure.
Once exposure is set, you can start getting good shots.

Careful when you photograph longer because light will chance. For example in early morning you may need ISO 1600 but 20 minutes later it can be bright enough for 400 or less.
Also make sure to notice passing clouds. They take away light and the bird will be overexposed.

If a black bird like a crow flies buy, you will need to correct exposure as a correct exposure for a mostly white gull will often result in a too dark crow without any feather details. There is only so much magic Lightroom/Camera Raw can do with an underexposed black bird.

Midtone birds, e.g. Greylag Goose or Steppe Eagles are the easiest.

I use AV a lot but rarely or almost never for BIF.

Markus

John Chardine
08-21-2013, 04:08 PM
Hi Iain- Good advice above. To specifically answer your question, when using manual mode you do not "meter" during your normal photographic activities. When you do "meter" is before you start whereby you spend some valuable time determining the best exposure setting for your subject. This may involve initially taking a reading in Av mode of a neutral subject lit more or less like your subject and then through trial and error arriving at an optimum exposure for your subject. The trial and error process involves making an exposure and examining the histogram to make sure your subject is well exposed and not over, or under-exposed. Then you periodically review your LCD and histogram to make sure everything is OK or adjust your exposure with changes in light, which invariably occur. Setting your camera to show over-exposure in the highlights (blinkies) is very useful. Some starting out in birds in flight photography will recommend spot metering the subject as you photograph your subject. However, this is impractical mainly because your subject will take up varying area of the frame and if small, your metering spot will include some of the background. It will also include the background if you drift off the target as you track your subject.

Iain Barker
08-21-2013, 05:51 PM
Thanks everyone for the advice it's all very useful.
I'll try and put the advice given into practice over the next few days. I have had some good results in Av mode but think this is what I need to do to take my flight photography to the next step.

BobbyPerkins
08-21-2013, 07:54 PM
Because of constantly changing backgrounds with BIF photography manual mode is pretty much a requirement (if you want consistantly correct exposures).

Jim Neiger has posted some excellent info on this topic even here on BPN. Regarding the issue your having with "Manual metering of Birds in Flight", heres an excellent tutorial by Jim that may help.

http://photocamel.com/forum/tutorials/141176-photographing-birds-flight-1-exposure.html

Bruce Spell
08-21-2013, 08:33 PM
When using the manual mode technique do folks also manually set ISO as part of this or let the camera set auto ISO to suit the f-stop/shutter speed combination? I'm assuming you set the ISO as well so that the overall exposure is not changing while you are shooting...

John Chardine
08-21-2013, 08:41 PM
Correct!!!!!!!!!! Just to be clear, do not set auto ISO!

Diane Miller
08-21-2013, 10:00 PM
Jim's tutorial is excellent, but (unless I missed it) he doesn't mention the best "constant" -- a gray card -- available at camera stores. (A hassle to carry around, but it IS constant.) Keep it parallel to the sensor, in the same light as the subjects. Shoot the thing filling the frame (does not need to be in focus). Also excellent for getting a correct white balance.

One problem -- I have two, and they are both different, both in darkness AND in color. One is slightly blue-green and lighter. The darker/lighter part is easy -- shoot it and make whatever exposure compensation puts the histogram peak (which should be very narrow) in the middle. Then compensate from that as Jim discusses for different subjects, if necessary.

John Chardine
08-22-2013, 05:51 AM
Hi Diane- IMO a grey card for this application is just a waste of space in your bag. When I teach manual exposure, people almost panic in anticipation of the process of coming up with the initial exposure. That is, until you explain how easy it is. There are plenty of "grey cards" out there in nature or just take an exposure reading of any mixed-tone scene. You may be off a little relative to the optimum for your subject but it's a starting pointing from which you can home in on the correct exposure in literally seconds with a few test shots.

BobbyPerkins
08-22-2013, 07:09 AM
I agree with John and is exactly what Jim Neiger outlines as "Substitute Metering" as your base exposure. Then your comparing your subject to the metered constant and compensating accordingly.

Jim Neiger
09-26-2013, 03:20 PM
Because of constantly changing backgrounds with BIF photography manual mode is pretty much a requirement (if you want consistantly correct exposures).

Jim Neiger has posted some excellent info on this topic even here on BPN. Regarding the issue your having with "Manual metering of Birds in Flight", heres an excellent tutorial by Jim that may help.

http://photocamel.com/forum/tutorials/141176-photographing-birds-flight-1-exposure.html

My new E-book is now available. It covers this topic and a lot more. It's available in the BAA store.

BobbyPerkins
10-01-2013, 09:45 PM
Excellent Book Jim!