View Full Version : major blue on stage show


Jim Stamos
October 17th, 2015, 10:00 PM
i know colored lights are not our friends. was shooting lion king at a school.the shows lighting was mixed, some very dark scenes and some very bright. at one point they had some colored lights on that werent really noticeable on the stage, but one must have been blue, because both of us shooting with our ex1rs had major blue on our lcds. i guess its what the camera see. in the edit, it obvious and i cant do anything about it. im sure the parents will wonder, but ill make it clear to the lighting people that for video dont use colored.
anyone else had this ordeal??
jim

Dave Sperling
October 17th, 2015, 10:33 PM
I'm assuming that you're talking about blue from LED par lights and not blue from HMI follow spots...

We often have trouble with washes from Blue LED lights when shooting Broadway stage productions -- some LED brands seem to have an exceptionally low CRI (color rendering index) and the light in the near-ultra-violet part of the blue spectrum can overload the blue channel of the camera -- making everything they hit blurry (and of course overly blue.) If we shoot setup scenes during the day we can usually get the lighting designer to adjust the colors for us (we set up a sony OLED monitor for them to look at), but if we just go in and shoot with the existing show lights we warn the client that the blue scenes may be unusable.

We do seem to have better luck when we shoot with F3's rather than EX's, and presumably the expanded color gamut of the F55 would be the best option (but we don't have the budget for that.)

If you know you are going to be in that kind of situation and also know you can deal with color correcting everything, you might want to look at reducing your chroma levels as well as setting your color balance to a higher temparature -- knowing that you'll be working with the colors in post...

Mike Watson
October 17th, 2015, 10:43 PM
I stopped shooting school plays ten years ago, but in the ten years prior to that I had hired guys who had delivered pretty dodgy footage at times - out of focus, bad framing, shaky, etc.

The one thing I can say to console you is that no matter how bad it was, I was always sure to get some parent asking me "why did you shoot so much of little timmy and so few shots of my little johnny??"

And in all those years, never had a parent complain about a technical detail. I once delivered 50 DVDs that had "MEDIA DISCONNECTED" instead of the wide shot for about 20 minutes toward the end of the production, and I didn't find out for SIX MONTHS after delivery, and only then because *I* opened up one of the DVDs to have a look at something. NO ONE EVEN WATCHED THEM.

David Heath
October 19th, 2015, 11:54 AM
And a major cause of the problem is often overexposure. The colour channels are matrixed to form luminance and (from memory) the equation is Y=0.3R+0.69G+0.11B. Hence if there is only blue light, the MOST the luminance signal can ever be is about 10% of maximum. That's pretty dark, and if exposure control is being done from a monochrome monitor (or waveform monitor looking at Y) there is a strong tendency to overexpose.