Color Shift

[Steve Gooderham]

Any suggestions please, I have just finished a shoot using my canon XL1S. The shoot was in a all white studio (wall, ceiling and floor) it was lit using three 500w quartz halogen lights fitted with diffusers. When viewing the end result it is apparent that the colour of the background was cycling from white through to a pale green and back to white over a 45sec-1 minute cycle, the change is so subtle that we did not notice it during the shoot, but it is now painfully apparent. The only other time I have seen something similar was when shooting in an office environment under cheap flourescents (I learned a lot about the decay features on flourescents after that debacle) however there were no tubes on in the studio.

Camera settings were, exposure and shutter - manual, ND - off, stabiliser -off, focus - manual, and white balance - interior light, (I am not sure but I suspect that may have been the problem. The camera has only recently (within the last 5 hours) been serviced by Canon

I am going to try shooting a white wall with different settings to see if I can identify the problem, but has anybody experienced anything similar ?

Other than this the camera has perormed well.

Best Regard

Steve G

[Anthony Meluso]

I also work with an XL-1 and had seen this same thing before. Unfortunatly I never have a color meter around to tell me what my light source temperature really is. But manually white balancing the sence usually helps. Anything else can be done in post.

[Jesse Rosten]

Steve -

Had the same problem in a white room with the Xl1s and daylight balanced flourescents. The problem was not my white balance, but actually SHUTTER SPEED. My fast shutter speed was cycling with the frequency of the lights and caused the color to fluctuate. I'm guessing it's the same thing that happens when
when you shoot a CRT and you see scan lines. Try decreasing your shutter to 1/60th and see if that helps.

peace
- Jesse

[Filip Kovcin]

i do not know about xl camera, but...

i had very similar problem some time ago with (i do not remember the model/number) Digital8 sony camera, but i noticed that image pulses when you turn ON camera's image stabilizing system... sounds strange, but when i turned that off everything was ok. the same was visible also when shooting the tv screen (not computer!). when stabilizer is on - darker line appears with strange irregularity, when image stabilizator was off - nothing. the picture was ok.

maybe - (i'm not expert on this, and don't know how to explain it properly) - sometimes - if you (the camera) are connected to ONE "power line" and the lights ar on different one - maybe for some reason those frequencies are not in sync... so maybe you can see the "breathing".

just a thought.

[Jeff Donald]

Was the camera AC powered or battery powered?

[Ryan Gohlinghorst]

I'm inclined to agree with Jesse on this one. It's the shutter speed. That also explains Filip's problem because, with the image stabilizer on, the camera won't allow the shutter speed to be faster than 1/100th. I don't exactly understand why, but it appears that it happens.