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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 :)

Strobe ?

I remember reading on the HVX forums that Panasonic said the most "filmic" setting for the Varicam was around a 220 degree shutter angle. I usually ride my HVX setting between 180 and 215 depending on the shot. Helps you gather a little more light too.
 
Finner said:
I definately noticed judder with the milk girls stuff.
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I´ve noticed it too. Since I was seeing the clip on an old G4 Dual 500 I though it was a lack of processor speed. But now that everybody else see the same thing I´m concerned...
 
24fps strobes when panned too fast in either film or video. Poi is right on here.
ASC manual refers to this problem as it relates to film cameras and makes recommendations for operators about pan rates.
 
The fact and what´s being discussed here is that HD cameras @ 24fps and 180 degree shutter strobe harder than 35mm film at the same settings when panning at the same speed.
 
Rodrigo Lizana said:
The fact and what´s being discussed here is that HD cameras @ 24fps and 180 degree shutter strobe harder than 35mm film at the same settings when panning at the same speed.
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Sure this is what started being discussed but this kind of strobe is first year film student 101 stuff and I would expect anyone with a small amount of camera experience to know this.

What has come to light in this thread and is of real importance is if there is a studder problem with the red camera that a bunch of us have seen and no one has mentioned that it has been fixed or did not see this kind of problem in the LA showing. If the camera has a jutter problem like a bunch of us have seen it will be unusable. Which would be important for all reservation holders and much more important then basic camera knowledge.
 
Let me also mention that I am not jumping to conclusions that this is a problem that has not been addressed by red. I believe they probably have already seen and fixed this problem It would just be nice to hear that it has been fixed by red or that it was only a problem with early footage.
 
Additional judder/stutter like effects in movement have been seen in 24P since it's beginning as opposed to film. I think much of this is because we are looking at 24 frames per second in the recording viewfinder and also the playback. This same effect is visible in the film camera viewfinder, however When looking at film in a theatre since 1937 we are seeing each frame projected twice by the projectors butterfly shutter, so in a sense we are seeing 48 fps. This technology was developed to add smoothness to what were then called the "flicks"

Another fact that several posters have alluded to is that sharpening made it worse, and looks like 90 degree shutter. For those not aware usual 180 degree film camera shutter is an exposure of 1/48 second.

Now if you hand hold your slr and shoot at 1/48th the stills will be quite blurry this effect allows visuals at 24 to have a more acceptable motion.

I'm thinking the important aspect of this question is what are the shutter settings on the RED. can we lengthen the shutter opening? for that matter for sports/stills etc. can we shorten it?

Because shutters in digital cameras are electronic, not a mechanical disk, it should be possible to approach 1/24th sec. exposure at 24fps which would add even more blur (than film) to each frame and therefore make the motion even smoother.

Of course when converted to film and shown in a theatre the motion artifacts in milk girls will be reduced by the butterfly shutter. When shown on HDTV the footage will be converted to 1080I with a field rate of 60/fps. We should keep in mind that the HD24P format was intended as an origination format not a distribution format.
 
tj williams said:
When shown on HDTV the footage will be converted to 1080I with a field rate of 60/fps. We should keep in mind that the HD24P format was intended as an origination format not a distribution format.
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Ah, but HD 1080P/24 is now an official distribution and display format for both HD-DVD and BluRay.

I'm thinking that to relieve some of the juddering or odd motion we may see, will require a longer exposure vs. film camera. Or at least that's the only thing I can come up with. OTOH, I think it will depend more on delivery formats. Possibly some new thinking and techniques will need to be applied to D-Cinema shooting. I'm also hoping that RED has evolved a lot since the milk girls shoot and this won't be much of an issue.
 
TJ

The lab I use e-mails me 24p dailes of film that I have shot for quick reference and it does not jutter anything like the milk girls stuff. Nor is this a standard problem like what I have seen before with HD 24p footage, it is different. I am just really surprised that no one on the red team like Grahame or Stuart or Rob has posted anything to clear all this up?
 
Finner said:
The lab I use e-mails me 24p dailes of film that I have shot for quick reference and it does not jutter anything like the milk girls stuff.
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Quite right, this is different even compared with 90 degree shutter.
As Finner said it has nothing to do with accepted pan speeds, everybody knows that, it has to do with getting the right product. I´m afraid and concerned that this kind of strobe could remain on the production models.
BTW, "bringing this shit to light" doesn´t mean we want to run the magazine on reverse, it just means we want the best for the camera and the whole project !. I also want to know what´s Red opinion on the subject.

Regards
 
I´m wondering how does an on-chip shutter works...it just add darkness to a select area of the chip ?. If that´s the case I believe the reason might be there. The moving-mechanic optical shutter might left a remaining effect while it pass and let the light back into the film thus blurring the image. This is just guessing btw. Someone said in here that the D-20 had the same strobe issue as any HD camera so that might be proving my theory wrong...Red guys ?
 
The most likely explanation is that the shutter speed was "off" on that test footage. Remember Frankie is rather prototype. I don't think we'll have this kind of issue on the new protos.

Graeme
 
Also maybe part of the problem in milk girls is the playback... on 1/2 size it seems less motion artifacted on my computer than full size? I'm unfamaliar with the way the torrent download works, Could that also be part of the problem?

Finner: I agree that film transferred to 24P is less obnoxious generally than digital cameras original in 24P I've always felt that was because film is naturally softer edged.

Certainly if the original footage played back on the projector at nab looks like the motion artifacts in milk girls the RED folk have a serious problem.
 
Artifacts in any footage you've seen so far are irellevent, because Frankie architecture is not shipping camera design.

Graeme
 
Thanks Graeme.

I would still like to hear from someone at the LA showing as to what the milk girls and other moving shots looked like.

Anyone who was there your comments would be great.
 
If current workflow at NAB -40 is good it shouldn't take all that long off task to show us some current 1080/24P footage replacement. The current footage is disturbing!
 
We're disturb… we're disturb… we're the most… dis… turb, etc
sung on West Side story's "Officer Krupkee" tune.

I wouldn't mind the new footage though:tongue:

Or just a more firm confirmation that all is fine in Red's world.

Emmanuel
 
Finner said:
I would still like to hear from someone at the LA showing as to what the milk girls and other moving shots looked like.
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If the shutter was off when the scene was recorded, then the milk girls footage should have looked the same.
 
By "off" I don't mean turned off, I mean somehow "wrong".

Graeme
 
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