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View Full Version : rainbow halo around white in high contrast - why?



mopalia
06-19-2007, 10:34 AM
I'm taking a lot of photos on a salt flat marsh. When I take pictures of white birds, like egrets, I get a multi-colored halo around the bird. I know there's a word for this but can't remember it. What is it and how can I get rid of it?
Canon S2IS, no filters. Very high contrast situation, I think. I'm new at this kind of photography (CA light is not what Seattle light was!) and I'm figuring out this camera one feature at a time.

John_Reed
06-19-2007, 03:51 PM
I'm taking a lot of photos on a salt flat marsh. When I take pictures of white birds, like egrets, I get a multi-colored halo around the bird. I know there's a word for this but can't remember it. What is it and how can I get rid of it?
Canon S2IS, no filters. Very high contrast situation, I think. I'm new at this kind of photography (CA light is not what Seattle light was!) and I'm figuring out this camera one feature at a time.Some people call it "CA." On the other hand, I've shot a whole bunch of Egrets in your neighborhood, and I do know that they DEMAND underexposure. Their feathers reflect so much light, it can drive a camera's exposure system crazy if left un-checked. Here are 3 examples in 3 different lighting conditions, the first in overcast at: -1/3 EV:

http://john-reed.smugmug.com/photos/145273502-L.jpg

Second one a little brighter, backlit at -2/3 EV:

http://john-reed.smugmug.com/photos/145273348-L.jpg

Full sunlight at -1EV:

http://john-reed.smugmug.com/photos/143626362-L.jpg

In the last one, you can see that the wing leading edges are already verging on being "blown-out;" but if I'd made it any darker, the underbelly would lose details.

My shots were taken with an FZ30, but a friend of mine who shoots a DSLR says he has to be really careful with Egret exposures too; it's not unique to you.

mopalia
06-20-2007, 09:15 AM
Yes, that's the term I'd forgotten. Your pictures show me why the ones taken on the day I'd forgotten that the shutter speed was the default, resulting in really dark pictures, didn't have this. And now I know which camera feature to explore today! Thanks very much.:cool:

coldrain
06-24-2007, 02:08 PM
Can you post a crop of a photo to exactly show what you see?
If it is purple fringing, selecting a smaller aperture will help.

To correctly expose a white bird, put the camera metering into a smaller spot metering mode, most probably recognized by [( )].
Then the camera will expose for the bird, not the surroundings (is you have the bird in the center of the photo).

SpecialK
06-29-2007, 09:43 PM
To correctly expose a white bird, put the camera metering into a smaller spot metering mode, most probably recognized by [( )].
Then the camera will expose for the bird, not the surroundings (is you have the bird in the center of the photo).


Uh, won't that produce a gray bird?

Studentpilot
06-29-2007, 10:29 PM
Your thinking of setting your white balance to the bird. Metering is judges how much light will hit the sensor. Spot metering means it will meter of of a single spot as opposed to take the average of the frame or other metering modes (IE Matrix)

coldrain
06-30-2007, 03:12 AM
Uh, won't that produce a gray bird?
Isn't all white that is not blown out... grey!?

So no, you will not get a grey bird. You will get a white bird, will all the grey gradations a white bird has when not overexposed.

SpecialK
06-30-2007, 07:13 AM
Sorry, guys. The meter wants to make things middle gray. It will make black gray, and it will make white gray - unless you compensate.