# Color temperature changing during video shot (7D)



## ri_baptista (Mar 23, 2017)

Hello!

Yesterday I shot some videos with my 7D and after downloading the videos to my laptop I noticed every movie starts with the correct color temperature and after a few seconds the colors seem a lot hotter.

Does somebody knows why this happens and how can I prevent that?

Here are some facts:

* I was using Live View so I could trigger movie recording remotely from my laptop (I was shooting alone).

* I recorded SEVERAL takes within a period of 4 hours, each take lasting about 2 minutes, and waiting about 1 or 2 minutes before starting recording the next take (sometimes I started immediately). I kept just the very last ones, so I don't know if this issue was happening during the first takes. Could this problem be related to camera sensor working for hours straight, even taking a break of 1 or 2 minutes between each take?

* Light sources remained constant during the entire recording session.

Below are some screenshots so you can see what I'm talking about:

Thanks!

AT THE START OF THE VIDEO:






AFTER A FEW SECONDS (notice how skin tones changed drastically):


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## FotosbyMike (Mar 23, 2017)

Was your WB set to Auto anything or manual? If it was Auto anything the glare off the guitar appeared too cool(Blue) so it warmed(adding yellow) to the video.


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## KmH (Mar 23, 2017)

What type of light is your light source? Fluorescent? Tungsten? LED?


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## ri_baptista (Mar 23, 2017)

Hi @FotosbyMike

That makes total sense... I've just checked WB is set to Auto on EOS Utility Software. Tonight I'm gonna try to set it to a fixed value (fluorescent).
I didn't know an Auto WB setting would make it dynamic DURING video shooting. I thought it would remain constant after video recording started.

Thanks!


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## ri_baptista (Mar 23, 2017)

Hi @KmH!

It is a fluorescent lamp.


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## KmH (Mar 23, 2017)

As fluorescent lights cycle through the AC voltage range (+60 V to -60 V) their color temperature changes making fluorescent lighting a poor choice for shooting video.
Particularly if you have the White Balance set to AUTO.

The other issue with fluorescent is flicker, again because of the voltage cycle rate - 60 cycles per second in the US.
To shoot video with a DSLR we want to set the shutter speed to 2x our frame rate, which puts us on shutter speeds too close to 60 cycles per second.


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