Take is going from normal to extrem overexpose

[Sebastian Cramer]

I was shooting a commercial today with two cameras. Both cameras are build 16.3.2.5, recording to CF in 3K 16:9 at 44fps. All mags have been formatted in camera.
B cam was shooting four mags. On two mags the first scene (in one case the seconde shot also) was going from normal exposure to extreme overexposure after the first 2 frames which looked good. The entire scene then stayed on this high level. It only happend on first takes of a mag. Other stuff looked good.

It's definitly in the R3D as it can be reproduced in RA and RC (enclosed frames are RC output/DPX converted to jpeg).

Any ideas? Anyone has seen this before?

Thanks,
Sebastian

 

[Sebastian Cramer]

Sorry, got the wrong reference frame, the red pixels in the normal exposure are not in the shot. Here is the right reference frame.

 

[Philip Powell]

I'm not certain it's the same but I'll mention it.

I'm not certain it's the same but I'll mention it.

But we had a similar looking event occur on an overexposed shot. I started a thread but nobody ever responded. First frame was fine then the blue channel got all whacked out and eventually popped back into place near the end of the shot. (3K 60fps build 16)

http://www.reduser.net/forum/showthread.php?t=17378

Check your histogram, does it jump at the transition point? On all channels or just one? Also the grid pattern that we all saw at full rez.

Again, not certain it is the same problem but thought I would mention it, as it kind of looks the same to me, and both shots shared overexposed elements. EDIT...I just reread your post, and I perhaps misundertood it. Are you saying you overexposed the shot while shooting? (which is what I thought you meant) Or that the shot "jumped" into a state of overexposure during shooting? Just MHO, but it doesn't look so much like overexposure to me, as it does a channel dropping out, i.e you've lost your Red or Blue Channel.

 

[Florian Stadler]

Looks like it's missing the red channel