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Felipe Jaco
10-16-2008, 02:12 AM
On every RED ONE shoot I have seen so far there are these flickers or some kind, or lines which appear every time when camera or objects in the shoot are moving. I think this is the biggest thing that it pushes it away from looking like film footage. I don't know how Soderbergh fixed this problem but I doubt he or any other good director would tolerate this. I mean it is so annoying, looks like picture is cutting it self constantly. I have this problem with my HVX200 and those are rolling shutter issues, am I right?

Gunleik Groven
10-16-2008, 02:20 AM
how are you looking at the footage?

Brandon Fraley
10-16-2008, 02:21 AM
with the exception of strobes, I've never seen ANY red footage appearing like you described. I'd definitely have your camera looked at.

Gunleik Groven
10-16-2008, 02:25 AM
I can recognize the description from when you look at footy in RC/RA and even in Scratch. If it is this symptom, it's a preview issue and has nothing to do with the actual files, but with uncompressing and computer horsepower.

Sander de Regt
10-16-2008, 02:29 AM
Since the HVX200 has CCDs I doubt it's a Rolling Shutter issue, since that's a CMOS only thing.

Gunleik Groven
10-16-2008, 02:30 AM
No, it's not a rolling shutter. But I think it is a preview issue.

Does this happen when you export your dpxs?

Felipe Jaco
10-16-2008, 02:34 AM
I can recognize the description from when you look at footy in RC/RA and even in Scratch. If it is this symptom, it's a preview issue and has nothing to do with the actual files, but with uncompressing and computer horsepower.

Now when you say this, it think you might be right. All dough I have pretty strong computer, it could be in compression. As I compressed one file in several different ways and the symptom was not always showing in the same amount.

Jason Sinclair
10-16-2008, 02:48 AM
So what system do you have...?

gnomer
10-16-2008, 05:01 AM
"Why it's strobing?!" is most common question about footage playback. It's about computer horsepower and nothing else.

Gunleik Groven
10-16-2008, 05:07 AM
Strobing happens, but this doesn't sound like it.

I've seen it in RED.... and in the D21 demo-footy @ ibc :)

It's there, and it cannot always be avoided.
The same thing is with rolling shutter skew. Sometimes it's there, but usually it's not much of an issue...

Mani Ghasemlou
10-16-2008, 07:28 AM
a totally uninformed, wild guess here, but maybe it's a v-sync issue on your display device. i.e. your monitor refresh rate isn't divisible by the frame rate of your media, so you're seeing the artifacts you describe.

Sudhir Chaudhary
10-16-2008, 08:03 AM
I saw this on my footage too, but only during playback in the editing suite. I agree its not rolling shutter but computer preview problem. If you have doubts the tearing should repeat itself at the same frame everytime you playback, so scroll back and forth to check that.

antique suede
10-16-2008, 09:25 AM
It canīt be an rolling shutter problem, because red donīt work with rolling shutter!? I rather think. Isnīt it so?

Jeff Kilgroe
10-16-2008, 10:00 AM
Symptoms of "lines" or breaks in the image are playback and display sync issues like "tearing". I have to ask what kind of computer is being used, video card, display, etc.. It's common to see strobing and judder for editing and playback and a lot depends on the refresh rate of the display, video card speed, CPU speed, etc..

RED does have a rolling shutter, but the effect is very low compared to most CMOS cameras -- especially when considering the resolution of RED. IMO, the "skew" effect produced by the lower read reset times ("rolling shutter") give the RED image a little bit of an organic feel and can help achieve a bit more of a "film look". People often forget that systems like film or even CCDs with a mechanical shutter element, will also have skew. Mechanical shutter systems produce skew with a different look due to the shutter being in front of the image plane, therefore out of focus, and it wipes across the image at an angle, not perfectly horizontal or vertical in most cases.

Kaku Ito
10-16-2008, 10:07 AM
I've noticed few rolling shutter issues on RED here and there, but from an ex-anti-rolling shutter guy (I kept making big noises about rolling shutter problems over at dvinfo.net and used to prefer P2 cams), RED's rolling shutter issue doesn't really kill RED, in fact, I sold my HPX555 (500 equivalent) and don't even touch HVX200 too often. Also, RED makes money but P2 didn't make money as much. RED did worked hard to minimize the rolling shutter issue.

Also, rolling shutter issues show up with the light source but so far we had solved with the shutter angle adjustment and also use high frequency lighting.

gbalaji
10-16-2008, 10:07 AM
On every RED ONE shoot I have seen so far there are these flickers or some kind, or lines which appear every time when .......

Are you seeing flickers on HD-SDI output or in Computer. Are you using HD Monitor and at what frequency you set your output in Camera / Display HD Monitor?