Why are my photos purple?

[CalamityJanet]

Does anyone know what might cause this? I was out early trying to capture the sunrise behind our vacation house and the shots taken during the first 15 minutes are horribly purple. Then it stopped and the rest were fine after that. All taken with Canon XSi and 10-22 wide angle lens, AV mode, auto WB, RAW. (I did a screenshot of my LR2 library to show what I mean.) It was cold, maybe 34 deg.F and windy. I formatted the card before I started shooting.

http://www.pixentral.com/hosted/19yRco3IDkUHKaFXcQjIBwXnHDqdM1_thumb.jpg (http://www.pixentral.com/show.php?picture=19yRco3IDkUHKaFXcQjIBwXnHDqdM1)

[Edmund]

When you look at them in RAW in the develope module what do they look like when you adjust the WB? Could be auto WB that early in the AM and it is fooling the camera.
Eddie

[CalamityJanet]

Hi Eddie,
In the develop module I change the WB from "as shot" to "auto" or "cloudy" and they look pretty close to what I think they should. I've just never seen this odd behavior before. I might get out early one morning soon and try to get it to happen again.

[ljameso1]

I also think the culprit was using auto white balance. At least you were shooting raw so could correct.

[lowbone]

Another for Auto White Balance. Next time you go out try a custom white balance. You can find out how this is done in the manual Keep in mind that as the light changes so will the WB.

[Codebreaker]

That's really strange because they're not all effected. I've shot with a Canon dSLR for about 5 years now and never used anything but Auto WB and never had anything like this.

That's a low temperature you have there and I notice its the first shorts that are bad. Where these the first shots after the camera was switched on?

Colin

[CalamityJanet]

That's really strange because they're not all effected. I've shot with a Canon dSLR for about 5 years now and never used anything but Auto WB and never had anything like this.

That's a low temperature you have there and I notice its the first shorts that are bad. Where these the first shots after the camera was switched on?

Colin

Yes, Colin, these were the first shots that morning. Like you, I always use Auto WB and between my XTi and XSi I've taken about 8,000 shots and I've never seen any thing like these purple clouds. I looked at the exif for some clues and the only thing that I see is that the first 15-20 shots have the longest exposures, from .5 to 1.6 sec. As the light increased and the speeds increased the purple disappeared. Could it be the temp of the sensor warming up caused it?

[JulieM]

Those are some funky skies! I too use Auto WB (shooting with the xTI) and have never seen anything even remotely like this. I can also say that in the winter months my camera is exposed to temps as low as -20 C (-4F) on a fairly regular basis and I've not observed a shift like that during the time the sensor might be expected to be warming up. I think I'd look at something other than Auto WB or cold temperture.

[CalamityJanet]

Those are some funky skies! I too use Auto WB (shooting with the xTI) and have never seen anything even remotely like this. I can also say that in the winter months my camera is exposed to temps as low as -20 C (-4F) on a fairly regular basis and I've not observed a shift like that during the time the sensor might be expected to be warming up. I think I'd look at something other than Auto WB or cold temperture.

Hi Julie,

I was astonished to see all that purple! My XTi (which now belongs to DH) and my XSi have both consistently produced good results with Auto WB. So much so that I seldom think about changing it to any other setting. Thanks for sharing your cold temp experience with your XTi...one less theory to explore. I guess I'll consider it just a fluke unless/until it happens again.