Re: Difference in Levels in Two Camera Shoot by Pat Ford on Aug 16, 2009 at 10:07:21 pm
Brian...here's some of what I wrote from the lighting pro forum. The thread has been more active there.
A saying I have is that with any major shoot you learn something new. This time it's to be sure the cameras match.
I have done this shoot twice before and we have have no problem with the cameras matching. This time we had trouble. I still do not know why. I could not get camera 2 to white balance the same as the other camera. It looked washed out. We became aware of this in the minutes before the show. The flash video is early in the program when the difference is most obvious.
Since I last posted, I went back to my camera tech shop and presented him with a tape of the same video as appears on the web. He ran the video through a vector scope and a waveform monitor. In a nutshell, he said that the chrominance was not far off; the problem was mainly in the luminance. Like you, he suggested I use a ND filter. I have tried to color correct to overcome these problems and have succeeded in improving the situation somewhat.
....time passes....
Eureka...maybe...One of the moderators of this forum kindly called and suggested that I check out the data code on the camera tape...heretofore I have been running the tape of the director's switcher output. So...I checked #2 camera. It appears early on that the iris was being rapidly moved to various settings as wide as 2. Also, the gain seems to be being messed with...it went as high as fifteen...the movement is so erratic that it is possible that it might be a camera malfunction.(?)In any case by the third and final tape the erratic iris movement has ceased; the camera is set at 5.6 and the gain at 6db. And, as I understand it, a setting of iris 5.6 and 6db gain would roughly equal an iris of 4 and 0 db on the other camera. The third tape on the #2 camera matches #1 fairly well.
Strangely the gain on the second tape on camera #2 is 15 db. There does not seems to be a noticeable amount of noise.
If the gain was the problem...and indications are that it is, it is unfortunately my fault. The camera guy did not notice it, but I was acting as a producer/production manager at this event. Furthermore, it's my damn camera. If the gain was set incorrectly...it was almost certainly showing on the camera lcd screen. The camera guy did not see it nor did I. Seems crazy and unlikely but that's the best explanation so far.
Brian...added for your comment...I believe the camera was on automatic...that explains the wildly wavering data code settings.
I might add...the back was a fuzzy black material...kinda like velcro...can you say black hole for light? Also most of the girls had white or light colored dresses. Then the two spots! Like the #1 camera guy said, it is like trying to shoot a supernova!
Anyway, tomorrow I hope to go down to the post house and get with my editor and see if we can figure out a strategy to turn this sow's ear into a silk purse.
Might add also...the director was good about favoring the #1 camera (the one not blowing out) and...for whatever reason...the #2 camera looked better as taping progressed. By the third tape it was fairly decent...at least in the ballpark.
Anyway...it's up to me to fix it. Thanks for your help.
