Anyone have any idea what these are? Please help!!

[Chris Leising]

Hi,
So, I've been shooting on my c300, and noticed these weird gamma-artifacty scan line things in certain parts of the frame whilst shooting in this mental health ward/hospital. I'm shooting at 24p and 1/48th. Shooting c-log. Logging and transferring mxf clips into fcp 7 as prores. Here are some ungraded pictures. You can see what I'm talking about in the lower right part of the frame in the first pic, and on the back of the subject's navy fleece in the others. It's almost like a mix between mild scan lines and compression artifacts. Any info would be MUCH appreciated. Thanks, all!

[Barry Goyette]

I saw something like this last week on a dark neutral grey background we were using for some interviews. In FCPx it appeared almost like a weird tv scan sync problem, as the screen pulsated in the areas with the background. It was less visible in quicktime, but there was definitely some linear noise that I've never really noticed before. I tested at a variety of iso from 320 to 1250, and it was present throughout the range.

Barry

[Mark Koha]

Well, shooting in a mental health ward, the only thing that comes to mind is it's gotta be ghosts.

[David A. Fisher]

Did you adjust your shutter to the hrz rate of the fluorescent lights in the hospital?

[Darren Levine]

were you shooting 24P or PF?

[Chris Barcellos]

Looks like enhanced noise in underexposed area associated with scan lines resulting from florescent lights.. Had this occur with the 5DII in florescent lighting. Wondering whether your conversion process added to the noise. What about raw material. Same issue ?

[Chris Leising]

Hey, guys, thanks.

Yes, I shot some stuff at 1/60 to see and it didn't make a difference.

Everything is shot at 24p. I got the same thing when I was shooting this exterior at night.

What the hell is up with this linear noise?!?

Thanks for the help

cl

[Chris Leising]

Chris B- checking raw footage now

[Murray Christian]

As much as discovering the little details of a new camera w.new sensor etc is important and I don't blame anyone...I can't see a damn thing!
Is it really obvious in motion? If not I don't think there's much to worry about (so long as the audience is watching on a relatively well calibrated screen. Not something you want to bet on I know)

[Chris Leising]

I brought up the mids so you can better see what I'm talking about here.

[Chris Leising]

@ Murray- It's not that noticable, but I cant say that is putting me at ease!

[Mike Marriage]

I have had an issue with this too!

As below it was when shooting an interview against a dark grey gradient background. I was using selective colour correction and the effect became fairly noticeable.

Unfortunately I am unable to post the clip as the film is not yet release but I may be able to take a still of just the background if I can find a suitable section. Lighting was Kino Divas and Litepanels LED heads shooting at 25p. I think the issue is coming from the sensor.

[Chris Leising]

thanks, Mike, please post a still here when you can.

[Murray Christian]

Originally Posted by Chris Leising

@ Murray- It's not that noticable, but I cant say that is putting me at ease!

Cheers for the pic.
Don't worry. I'm one who would never buy an aperture grille CRT back in the day just because the two little suspension wires would bug me no end. So I know what you mean.

[Chris Leising]

Here's a little clip of it. I brought up the mids so that you can see better what's going on.

c300 footage on Vimeo