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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Strobing

C

Chris Vincze

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Hi there,

Just upgraded to the release build 16, and have noticed really bad strobing on even very slow pans - faces as well as hard verticals. Nothing that would be out of the ordinary on even very slow dramas, but the pictures are unusable.

Has anyone else noticed this?

Chris
 
Is this possibly due to the new image processing for build 16 or an artifact of the larger 16:9 4K image? Anyone from RED got any ideas? It's not like this kind of artifact isn't present in other cameras - even film cameras. It just seems to be more dramatic.
 
I have also noticed that on build 16 when panning and tilting the picture seems to shudder more. I think build 16 is great, but this does seem to be the last major issue that needs looking at.
 
Are you seeing this everywhere you view your footage? I know there were some people seeing this before on the EVF, where it turned out to be a change of the EVF refresh mode setting.
 
I am mainly seeing it on faster frame rates when tilting or panning, could be a shutter setting, will have to test further. It's there when viewing back raw and processed footage on a broadcast monitor.
The effect is at it's worst when camera is tracking sideways past vertical lines.
 
We did again last week a side by side test RED with a ARRI 235 2perf and printed everything out on film and had again a direct comparison shot for shot. I saw that the shutter effect at a 1/50 exp. time at 25fps is at the RED footage a bit better... I was wondering. The problem of the rolling shutter at faster pans is there as it is at every cmos camera with an electronic one. The only problem we saw was the low light noise at the blacks in build 16. We added no noise reduction at all in the post process so we saw a digital noise there what was not seen as grain. It was digital noise specially in the blue channel.... But over all the RED did a great job against 35mm. Over all the footage looked amazing....

cheers

rainer
 
Great info Rainer... So you're saying that the motion judder between Red and 35 film is comparable or that the Red has less judder than film?
 
I have to say it depends a little also on the focal length. If you have a wide lens and a lot of detail in the picture, specially vertical lines it is a little more visible as on 35mm. But not that much that I would say it is a problem. But in the most cases the motion judder of RED matches good with 35mm.
One test was done compared with ARRI D-21. Also at this comparison both are nearly the same, also, and that really wondered me, in the look.....

Macgregor what exactly do you mean ??
 
To alleviate strobing on 35mm panning shots some people employ a shorter exposure time by changing the shutter angle (90 degrees, 45 degrees etc), depending on the length of the lens and the panning speed - I'm assuming this would make no difference to the Red camera?
 
Also: www.macgregor.autoecstasy.com/bikerstrobe.wmv

It´s very distracting and unconfortable for audiences. We printed these clips to film and once projected (digital and film projection) in a theater screen is even worse, the size makes things worse.

I still don´t understand why this happens. A 1/48th of a second is a 48th of a second. CCDs cameras didn´t have this issue, film didn´t have this issue. I wonder if the newer CMOS cameras show movement in this way too.

CLose ups are a bit of a problem as well as fast movements.
 
Judder

Judder

Can someone from Red respond to this?
Click to expand...

The response is, its not a suprise to see that with such a deep DOF and fast panning rate.

Has anyone done a side by side test that shows that this is actually different than on other cameras?
 
I don't believe it has anything to do with ccd vs cmos vs film. RED is sharper than what we've seen before and the especially since there's no grain, it's easier for the eye to lock onto each frame's details.

For panning shots, I now open up to 1/40th or maybe even a bit more and it looks very pleasing.
 
Show us a side by side test with 35mm scan with red footage.... would be really interesting.... for sure the motion judder could be improved, Stuart, if there is any time to have a look for it, we all will welcome a improvement to this... but it is not a hell more to 35mm....
 
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