View Full Version : Gray frame corruption on gunshot scene.
Noah Richoz
03-31-2009, 04:23 PM
I'm working on a show and we just finished a scene with some gunfire. On one of the shots during the gunfire (Camera distance to gun was about 6 feet ) we experienced some dropped gray frames during the gunshot. We're shooting RC36 MAX 4K with Hard drives. Was it the gunshot blast (full load banks) that made the corruption? The flash? The clips still do import into redalert.
Thanks,
any input would be helpful.
Colin Sheldon
03-31-2009, 04:57 PM
I would say the shockwave. We shoot a lot of westerns out where I live, and nobody I've worked with uses full load blanks. Half or at most 3/4 is all you need, especially at that distance.
sander kamp
03-31-2009, 05:04 PM
The hard drives are sensitive for vibrations, which includes load sounds.
Nick Gardner
03-31-2009, 05:19 PM
Non guns fix this problem, really safe, mussel flash last 2-3 frames, not loud. It doesn't help after the fact, but for the future.
Nick
David Guest
03-31-2009, 06:21 PM
As Sander said, the drives are extremely sensitive to vibrations. I'd almost guarantee it was the blast from the gun, considering you the length of the actual disturbance and the fact it was only a few frames that you lost. Were the dropped frames reported in the EVF/LCD? I only ask because we used the drives in a chopper, once... the dropped frames stacked up very quickly (something like 350 in a minute). We moved to cards.
Cail Young
03-31-2009, 06:29 PM
Definitely the shockwave from the blank firing.
Noah Richoz
03-31-2009, 06:31 PM
... Were the dropped frames reported in the EVF/LCD? I only ask because we used the drives in a chopper, once... the dropped frames stacked up very quickly (something like 350 in a minute). We moved to cards.
The dropped frames were not reported on the EVF/LCD, that's what really bothers me. I've seen dropped frames reported when they are green, these gray ones seemed to slip by. Anyone have an answer for that?
David Guest
03-31-2009, 07:29 PM
Sorry mate - that's a weird one. I'm clutching at straws here - but could it be a combination of the vibration/shockwave from the blast and the amount of colour information in the frame changing very rapidly? I've seen a couple of odd things happen with the camera when moving from areas of little or no contrast to areas of massive contrast (ie: a whip pan from a very dark wall to a very bright window).. in that case, however, the camera refused to record any further, rather than simply dropping frames. Bear in mind this has happened to me very, very rarely. I suppose the question then becomes how much of the frame was occupied by the actual blast?
Really just a shot in the dark, but it'd be good to work out.
Jannard
03-31-2009, 07:58 PM
Never use drives in this type of situation...
Jim
jbeale
04-01-2009, 12:05 AM
maybe the red drives should ship with some kind of "warning" piece of paper you have to tear through to get to the drive explaining the sound wave thing..
It's not a bad idea, but I think several of the folks reporting this issue in the past were using rented cameras. Embossing a shock/loud sound warning on the drive housing itself might be seen as a bit much... but maybe it isn't.
Josh Negrin
04-01-2009, 03:28 AM
the problem with a non-gun though, guys like me can tell the difference and are taken out of the film. Unless, of course, you paint in the slide action in after effects. Thanks for the heads up on this though, good to know.