The "POWER" of CMOS' famous rolling shutter

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Willis Chung

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Random clip i watched on youtube. Chances are you filmmakers will not need to worry about this, but... there are chances you would think about what would happen, and this is what would happen...

http://www.youtube.com/watch?v=lzzTFJWOOXk&feature=related

now you're probably like... well shi*... im back to thinking about the hpx170 again... but ask yourself... are you a papparazzi... or are you a filmmaker. it's like an RPG... there "IS" a reset button.
 
Thank goodness for the rolling shutter, with a CCD you wouldn't have seen anything of the clip as the whole frame would have been over exposed from all those flash's.

There were lots of partial exposed frames where the flash only exposed the bottom quatre of the frame and the rest of the frame remained uneffected so the flash went by un-noticable, can't get any better than that.
 
Sumfun, I was referring to the quickly flashing lights at about 1:00 into the video, when they begin to 'strobe'. I thought the EX1 handled that quite well.
 
Buck Forester said:
Sumfun, I was referring to the quickly flashing lights at about 1:00 into the video, when they begin to 'strobe'. I thought the EX1 handled that quite well.
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Yes, I was referring to those lights, too. But if you look at 0:47, 1:12, and several other times, you can see that they are constantly on, and not flashing. These types of stage lighting, although they can be made to "strobe", have much longer duration than flashtubes used for still photography.

Also, in this case, the "strobes" were used as backlight. This would have less effect than if they were the key lights.

I agree with you that the EX1 handled the lights well, but that's to be expected in this case.
 
Ahhhh... well I'm not that technical I guess, ha ha! Gracias for the clarification. I just saw some very fast extended flashing and called it strobing. I don't shoot in those conditions so to be honest I wasn't expecting the EX1 to shoot something like that so well because the strobing seemed pretty substantial.
 
The video looks really good.

True, the EX1 handles stage lighing fine. I have Elation and Martin moving heads that have a "strobe" function. No issues.

These particular heads use a mechanical shutter for the strobe effects. Even at the fastest speed, the EX1 has no partial exposures. Now aim a camera's flash at the EX1, that's a different story.
 
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You know, I think people make too much of the rolling shutter issue. Okay, if you're doing news stuff like that then yeah, maybe the rolling shutter problem will affect you with bulb flashes. But go beyond that with other types of shooting (ie. filmmaking, documentary, regular ENG work) and there's not that much of a problem. My HV20, for instance, has only ever acted up with rolling shutter problems when I tested lightning effects with a Halloween strobe light. But when I rented a flicker box and tested the lightning settings, there were no problems whatsoever even on the fastest settings going off constantly. Folks, you can't let one little imperfection prevent you from using a truly great tool, whether it be an EX1 or even a RED One.
 
Buck Forester said:
Do we know what camera was shooting that first clip? Not all CMOS are created equal.
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I sincerely doubt it was an EX1.

I shot some fireworks on the 4th and there are some one frame white bursts (the stuff that designed to make loud exposions only) and the EX1 handled it all perfectly. That was the closest I'll ever get to giving my cam the rolling shutter stress test.
 
As far as rolling shutter goes the flash problem is way less concerning than the jellovision© issue.
Unless you are a paparazzi.
 
What I assume you mean by jellovision is even less of an issue than the flash non issue. 99% of footage that might show some form of motion distortion would be thrown out in post anyway. Even then, I have yet to see this issue in any way in all my EX1 shooting including lots of run and gun shooting. The only time I have seen it is when deliberately try to create it.

The only people concerned about this one are people with P2 cameras trying desperately to justify their own low res CCDs, lol...
 
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Like any tool, you learn how to operate it correctly. The only people who complain are those who don't know how to use it, or those who have not used it.
 
RDykmans said:
I sincerely doubt it was an EX1.

I shot some fireworks on the 4th and there are some one frame white bursts (the stuff that designed to make loud exposions only) and the EX1 handled it all perfectly. That was the closest I'll ever get to giving my cam the rolling shutter stress test.
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I shot fireworks with zoom lens to get right into it, and it does show up the rolling shutter effect on the rapid flashes in the grand finale. Especially on overcranked footage.

If you shoot fireworks wide angle, the problem is likely to be less noticed because the intense portions of the flashes cover less than the whole frame.
 
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