People ragging on the 7D/any CMOS cam seem to be FULL OF IT

bwwd said:
With all respect Barry but i dont believe that,also i tested that in DSLR strobing is more noticeable when panning left-right than up-down(why i dont know).
I have 20p canon and 7D in 24p strobes almost as much as in 20p.I also have camcorder with 25P and tested 25p in 7D which strobes more.
Guess i would have to make video to have some proof OR maybe i made some mistake somewhere, we will see.
I also talking about judder in static shots which i never saw in movies shot on film.But saw on 7D stuff and RED stuff.
It would be good if i am wrong because it would mean that you just have to work harder to get rid of stuttery footage.
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We heard all these same complaints about the DVX, and it didn't stop until I put a 16mm movie camera strapped physically to a DVX100 and demonstrated that they are, in fact, identical in strobiing. Identical.

So I have no doubt that the 7D will perform the same. I could try strapping the 7d to a dvx and verifying, but I don't really feel like spending another $300 or so on film/processing/transfer to show it's the same as a film camera. I am quite very confident that any such test would indeed show that they are the same in motion.
 
Ian-T said:
I just think Cameron prefers 3D to be viewed with the more realistic motion of higher frame rates. It makes sense. The idea behind 3D is to give the viewer the sensation of “being there.” 24p is still suspended reality and is perfect for 2D viewing…but in order to get a more “realistic” 3D experience the motion has to match (IMO).
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yeah I don't have a problem with 3d being at a higher frame rate- I think it'd be more ideal since the projected frames alternate between left and right. Also I do think certain things should be at high frame rates (60p if possible) like sports or other live events (news, award shows, talk shows).

I was just wondering how 48fps looked in general, I'm guessing it might look a little videoy but there's a chance it might not. If it somehow maintained the same cadence or whatever of 24fps then that would be pretty sweet.
 
I will record in friday 25 7D against 25p in canon camcorder because 7d was more strobey for me.
 
bwwd said:
I will record in friday 25 7D against 25p in canon camcorder because 7d was more strobey for me.
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I'm willing to bet good money that the only reason the 7d "strobed" more is that you had it on a faster shutter speed.
 
I dont think so ,i know how 1/50 shutter looks in my camcorder and when i checked 1/50 shutter on 7d i was surprised by stutter.But i could made a mistake so im willing to change my mind about this with proper proof ,ill test it in friday.
 
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Do you get that same “strobey” impression when watching other folk’s videos online (I mean “downloaded” footage of course).
 
LOL…you picked one of the worst hand held rolling shutter artifact ridden video as an example. IQ looked cool for viewing online….but not a great example.
 
bwwd, watch DVXFest MonsterFest "Bits & Pieces". That was shot on a 7D, in 24p mode, by someone who knows how to. Does that look strobey?
 
Guess not because i would notice stutter,its the one with little girl ? I deleted it yesterday while cleaning up HDD,il download again but ill do test with 25 tomorrow anyway.
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Ok ive seen it again and there is no strobing but also not that much movement,a lot of dialogs.
 
But with 1/50th you have to be careful about fluorescents and HMI lights, in NTSC territories. In those circumstances you must not use 1/50, you should use 1/60 instead.
 
How theyre dealing with this when shooting on film ? By changing shutter speed ? Or replacing light bulbs ?
 
Assuming a 48fps clip would play at half speed in a 24p timeline....could you play the clip back at 200% speed and have normal motion with twice the frames?

What would that do?
 
bwwd said:
How theyre dealing with this when shooting on film ? By changing shutter speed ? Or replacing light bulbs ?
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Well, film is shot at 1/48th second, not 1/50, so I suspect that that tiny difference might be enough. Someone correct me if I'm wrong?
 
It would result in frames getting blended (or dropped, depending on your settings).

So you'd have a case of where you have 24fps normal motion (through frame dropping) and instant 48fps slow-mo wherever you wanted.

Do you have an HVX? You can try shooting 720/60p and bringing it on a 30p timeline, it'll be the same as 48 on a 24 timeline...
 
Weston said:
Assuming a 48fps clip would play at half speed in a 24p timeline....could you play the clip back at 200% speed and have normal motion with twice the frames?
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No, it doesn't work that way. By definition, a 24p timeline will only count 24 frames for each second. If you changed a 48 fps clip to play at normal speed on a 24p timeline, then it will just drop frames to get 24 fps.
 
bwwd said:
How theyre dealing with this when shooting on film ? By changing shutter speed ? Or replacing light bulbs ?
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Film doesn't use a CMOS rolling-shutter sensor so it doesn't have the problem. Film exposes the entire frame for a goodly percentage of its entire exposure time.

If you're using narrow shutter angles, you can get flicker on film when using those types of light sources; for those, there are so-called "HMI-safe" speeds. For example, 24.000 is an HMI-safe speed, on film you can shoot at any shutter angle at 24.000 fps even under those magnetic-ballast lights, and have no flicker. However, if you tried to shoot at a non-HMI-safe speed, like... I dunno, 31fps or something, then you'll get some flicker. You won't get scrolling horizontal bands, you'll get flicker.
 
ydgmdlu said:
Well, film is shot at 1/48th second, not 1/50, so I suspect that that tiny difference might be enough. Someone correct me if I'm wrong?
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Film is shot at a wide variety of shutter speeds. There's nothing magical or sacred about 1/48. I've owned film cameras that had default shutter speeds of 1/40, 1/43, 1/50, 1/60, 1/80, and even 1/120 (Beaulieu 6008Pro, its default shutter angle was 90 degrees!)

Film is COMMONLY shot at 1/48, but there's no rule that says you have to, and various film cameras have various exposure times.

It's all about the shutter angle; the film cameras I've had have shutter angles of 90, 144, 156, 172, 180, 220, and 240 degrees (IIRC).
 
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