View Full Version : White Balance and Black Level Adjustments


Dustin Gray
April 3rd, 2008, 06:48 PM
I was talking to a friend that is in televison and he was telling me each time they set up a white balance that thier cameras have a switch for the black levels also.

Is it fesable on the ex1 to adjust the black levels on each shoot, if so by how much?

George Kroonder
April 4th, 2008, 06:13 AM
HOW TO: Manually White/Black Balance with a Vectorscope (http://www.provideocoalition.com/index.php/aadams/story/hot_to_manually_white_black_balance_with_a_vectorscope_and_paintbox/) by Art Adams on PVC.

The title actually mentions the use of a Paintbox, but you use the camera matrix controls for that (Picture Profiles).

George/

Bruce Rawlings
April 4th, 2008, 07:01 AM
The black balance is not something that is carried out every day as a general rule. Presumably the PP settings will ensure correct black balance on the EX1 depending on the one selected.

Bill Ravens
April 4th, 2008, 07:12 AM
yes, the BLACK level can be adjusted in PP. Whether it's wise to do so, without a waveform monitor, is another matter, entirely.

Michael H. Stevens
April 4th, 2008, 02:35 PM
I was talking to a friend that is in televison and he was telling me each time they set up a white balance that thier cameras have a switch for the black levels also.

Is it fesable on the ex1 to adjust the black levels on each shoot, if so by how much?

Black level, the point considered true black does not directly relate to white balancing which is a color adjustment to take account of the temperature of the light. The black level on the EX1 (not the black gamma) needs be set for every changed lighting condition while white balance may stay the same.

Having now put the EX1 to good use I can tell you it is absolutely necessary to set the black point for every shot for the best results. The histogram works fine for this. Read up on what Randy has written on how to do this with the histogram. It was Randy who put me onto this and it is the best piece of advice I have been given here.

Paul Burgess
April 4th, 2008, 05:09 PM
Could you please give the link for the Randy article?

Dustin Gray
April 6th, 2008, 12:01 AM
Having now put the EX1 to good use I can tell you it is absolutely necessary to set the black point for every shot for the best results. The histogram works fine for this. Read up on what Randy has written on how to do this with the histogram. It was Randy who put me onto this and it is the best piece of advice I have been given here.

Hi thanks for the info everyone, can someone direct me to Randys info on the histogram, thanks.

Alister Chapman
April 6th, 2008, 05:23 AM
Black Balance is different to Black Point. Black Balance is where the black or dark output level of the 3 sensors (CCD's or CMOS) is matched by adjusting the pre-amp gain or off-set. The Black Point is an adjustment that takes the combined output of the 3 sensors and allows an offset to be applied that raises or lowers the combined dark signal level.