Black Balance?????

[Gene Sung]

I'm going to get an FS700 soon. I've noticed that people mention "Black Balance" when talking about the FS cameras.

I've never done a Black Balance on the Canon's that I've used. My questions are

1) What does a black balance do?
2) Why is there an extra step for this on the FS cameras, and not other brands?
3) Is there an advantage to doing a manual Black Balance over a camera that does it automatically?
4) How do you do a Black Balance and how often?

 

[FelixGER]

Remember black balance will reset to default every time you turn off the camera.
I´m not an expert but I think the camera is black balanced perfectly for most situations but I can imagine when using it in a very hot environment you can get rid of some noise when black balancing a too warm sensor manually.

 

[danstone]

Some answers...

1) Black balance (or black shading) is basically a way of resetting the CMOS sensor's voltage. Sort of like a "reset" button to give you a fresh start. If you have a hot pixel, for example, a black balance will fix it.

2) Most professional cameras have a black balance feature buried in a menu.

3) You usually only choose the "black balance" option and the camera does the rest automatically.

4) There's a lot of debate as to when to black balance. I only do it once before a shoot. I've worked with some guys who do it every power cycle and even when changing lenses. Most manufacturers recommend it when going through drastic temperature changes.

 

[nyvz]

2) Why is there an extra step for this on the FS cameras, and not other brands?

Just be glad it takes a few seconds on the FS100/700... RED cameras take 20-30 min to black balance, and not so much any more but phantoms had to be black balanced between every shot from what I understand. And better to have control over when it happens since you don't want to just hope your camera is properly black balanced after you change ambient temperatures or even black balanced at all. Even the my GH2 has black balance, but it may be more critical for image-critical cameras especially ones that really push image quality and have bigger sensors since they may be more prone to having more current around heating things up and affecting the photosite voltage readouts before they get to the ADC.

Black balance is a good idea for any camera if you want the best image quality. Helps minimize certain kinds of noise (especially FPN), hot pixels, etc. Minimizing noise is critical for getting the most out of highly compressed video formats like AVCHD. You really don't want it to spend all its bitrate compressing fixed pattern noise or contrasty hot pixels nor do you want them in your footage.