yellow bias with high gain

[Jayson Crothers]

I'm shooting my first HD project soon. I photographed a series of tests the other day and while testing various gain levels, found something interesting that I hope someone could shed some light on.

 

Shooting on an F900/3, I shot at each gain setting, adjusting the lighting to compensate for more/less light. At +12db I noticed a subtle shift in the color of the image, just a bit warmer. At +18 the image leapt to being very biased towards yellow - our vectorscope and HD monitor both confirmed the image suddenly turning yellow.

 

Any explanations?

 

Two other questions:

 

-What's a clockit box?

-What advice/thoughts can people offer for shooting 2 HD cameras from a technical stance (my primary concern being sound and TC for each camera - I'm less worried about how this questions affects my work and more concerned with post issues)?

 

Thanks everyone!

[Elhanan Matos]

From my tests I have noticed that +12 and +18 db of gain is very saturated. What I did was desaturate the image about 50% using the saturation page in the paint menus, this looked about right ( I was not using a scope, so I was doing all this by eye) and I tweaked the Video levels until the white balance looked about correct.

 

-What's a clockit box?

-What advice/thoughts can people offer for shooting 2 HD cameras from a technical stance (my primary concern being sound and TC for each camera - I'm less worried about how this questions affects my work and more concerned with post issues)?

 

A clockit box is a device that will let you sync up time code between multiple cameras.

 

As for working with multiple cameras, I would recommend you get a DIT.