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hockeyshooter
3rd of November 2008 (Mon), 20:42
I shoot a lot of hockey pictures with my Canon 40D. I have noticed at times when I shoot a burst of pictures, say 5 to 10, that at times, that I will have completely different looking pictures, despite that fact that they are taken so close together. One will look perfect, then the nxt one will have a pinkish hue to it, then the next one is perfect. Is there something causing the White balance to alternate?? I cannot figure why the camera would be doing this. Any ideas? I have been shooting mostly in Program mode.. then setting the ISO anywhere from 1000 to 3200, depending on the arena.

FlyingPhotog
3rd of November 2008 (Mon), 20:47
I shoot a lot of hockey pictures with my Canon 40D. I have noticed at times when I shoot a burst of pictures, say 5 to 10, that at times, that I will have completely different looking pictures, despite that fact that they are taken so close together. One will look perfect, then the nxt one will have a pinkish hue to it, then the next one is perfect. Is there something causing the White balance to alternate?? I cannot figure why the camera would be doing this. Any ideas? I have been shooting mostly in Program mode.. then setting the ISO anywhere from 1000 to 3200, depending on the arena.

May be a couple of reasons:

- The lights themselves may be cycling their color (really...) and you're catching them on even/odd cycles.
- Are you shooting in Auto White Balance? Try setting one custom white balance off a grey card and use that for the whole game.

eigga
3rd of November 2008 (Mon), 20:51
yep, light cycling. Only way to avoid this is to add flash. Otherwise you just have to edit

FlyingPhotog
3rd of November 2008 (Mon), 20:52
yep, light cycling. Only way to avoid this is to add flash. Otherwise you just have to edit

Isn't there a way to avoid the cycle by either matching or cancelling it by shutter speed...

(Suffering a brain fade at the moment...)

eigga
4th of November 2008 (Tue), 12:15
Yes, but I think the required shutter to achieve that is around 1/40... basically usesless for sports.

Here is a good read on the issue...

http://www.sportsshooter.com/message_display.html?tid=20873

scot079
4th of November 2008 (Tue), 14:18
I think you can shoot 1/120 and you'll only see 2 cycles in your photo...or something like that.

hockeyshooter
4th of November 2008 (Tue), 16:02
Thanks. I had never heard of that before, but it sounds possible. I shoot mostly in AWB. I suppose I should adjust it to match the ice. I've tried it set to various light sources and never liked any of the results from those tests.

dmwierz
4th of November 2008 (Tue), 16:29
Whenever your shutter speed exceeds the frequency of the AC, you run the very real risk of seeing light cycling. No amount of Custom White Balance will eliminate this.

You can, however, do a CWB with your shutter speed set to 1/60s or less to ensure your white balance is OK when you're not getting the impact of the color cycling.

This topic is dicsussed at length in episode 3 of this podcast:

http://www.sportsphotographycast.com

As mentioned above (and in Guy Rhodes' SportsShooter post), if you overpower the AC lighting with flash or strobes you can totally eliminate this color cycling.

Ain't this fun?

hockeyshooter
4th of November 2008 (Tue), 20:51
If white balance adjustment is not the answer, it looks like I may just have to live with it. I can edit them to some degree after. It would be easier not to have too. I am only talking about a very small percentage of my pictures. I was just wondering if it was something I had done wrong, or some setting I had accidentally hit.

PhotosGuy
4th of November 2008 (Tue), 21:03
It's just something you have to live with unless you can kick in just a touch of fill flash.

317544

mpeters
5th of November 2008 (Wed), 12:48
Shoot RAW, fix in post....or shoot at 1/500th and always shoot 9 frame burst. 1 will be right (that's a joke BTW.)

You can find the color shifts by simply pointing the camera and the ceiling so that the lights are not in the frame and shooting a 6-8 shot burst.

Even worse - they don't all cycle together...

pwrmac
30th of November 2008 (Sun), 08:50
The lights usually cycle at around 60Hz and any shutter speed divisible by 1/60 can get you correct exposures more consistantly. Other than that fire away and cross your fingures that "the Shot" hit the brighter light cycle.