Strobing / flicker effect when panning in 24p

Steve Phillipps · May 19th, 2008, 10:11 AM

Nonsense Eric, I've not seen it with any other camera I've used. It obivously is a rolling shutter problem. Varicam doesn't do it, Sony 750 doesn't do it, Sony Z7 doesn't do it, Digibeta cameras don't do it, Canon Ex-1 hi-8 doesn't do it!
What you do get from Varicam etc. is a motion blurring but it's subtle. This is just horrible and I think totally unuseable for action shots.
Steve

Dennis Joseph · May 19th, 2008, 10:24 AM

I am curious if the other Cinealta cameras have a similar judder/flicker effect when doing slow or quick pans. Anyone have any f-900 or F350 footage we can check out?

Is there anything that can be done to reduce the flicker? There is a "Flicker Reduce" setting in the menu for 50hz and 60hz but I don't know if it is for that.

Steve Phillipps · May 19th, 2008, 10:27 AM

None of the other Cine Alta cameras will do it 'cos none have a rolling shutter. I've used an F900 and it's fine. The only way to reduce is to slow your pans down. Incidentally, the Phantom HD also has a rolling shutter but I've never seen an issue with it, I assume it must just scan the image a lot quicker (it goes upto 1000fps so I gues it needs to, and you pay abut £100,000 for this ability!)
Steve

Eric Pascarelli · May 19th, 2008, 12:17 PM

Quote:

Originally Posted by Steve Phillipps

What you do get from Varicam etc. is a motion blurring but it's subtle. This is just horrible and I think totally unuseable for action shots.
Steve

I don't understand what "subtle" motion blur is. Perhaps you can post an example of unsubtle vs. subtle motion blur?

Motion blur is regulated by the exposure time and how much the action before the lens changes during the exposure. Longer exposure means more blur. Shorter exposure less blur. Gamma can affect the hardness of the edges of the blur, but only subtly. Very bright things tend to have a hard edge blur because they saturate the sensor quickly. There's really not much more to it than that.

Rolling shutter is definitely there, and visible, and sometimes ugly, but it does not affect the "subtlety" of the motion blur.

Dennis Joseph · May 19th, 2008, 12:17 PM

It flickers even in the slowest movement though.

Steve Phillipps · May 19th, 2008, 12:28 PM

Eric, I'm saying that they are 2 different things. Motion blur is always there in progressive, but it's subtle, more subtle the faster the shutter speed. But the effect of the rolling shutter is not subtle, it's ugly.
Steve

Dennis Joseph · May 19th, 2008, 01:14 PM

Here is an interesting article that will shed some new light on this subject.

http://hd24.com/dont_shudder_at_the_judder.htm

Eric Pascarelli · May 19th, 2008, 01:18 PM

Quote:

Originally Posted by Steve Phillipps

But the effect of the rolling shutter is not subtle, it's ugly.
Steve

I have to disagree. Rolling shutter is not noticeable under normal conditions, but tends to reveal itself at the extremes. The judder you see is not related to the rolling shutter nor is it unique to the EX1.

Steve Phillipps · May 19th, 2008, 01:53 PM

If it's not the rolling shutter then what is it? Varicam/Sony 750 don't do it. They're the cameras I mostly work with, and they don't look like the EX1 does.
Steve

Eric Pascarelli · May 19th, 2008, 03:27 PM

Quote:

Originally Posted by Steve Phillipps

If it's not the rolling shutter then what is it?
Steve

Please figure it out and tell us all. Post clips if you can.

I can assure you it's not the rolling shutter.

Dominik Seibold · May 19th, 2008, 07:37 PM

I noticed, that the vlc-player plays videos more smoothly than the quicktime-player does (I'm using a mac). At 24p the vlc-player produces that typical 3:2-pulldown-look when viewed on a 60Hz-Display (like almost all LCDs do have), but the quicktime-player does it a bit more jerky. Another example is 60p: With vlc it's perfectly smooth, but with quicktime there are periodically emerging kind of synchronization-problems. I wonder how long we have to wait, until apple fixes that. Perhaps somebody has to tell it apple?

Dennis Joseph · May 20th, 2008, 02:41 PM

Do most of you play back your footage on a big screen HD tv?

Some things that may come into play as far as why there is flicker can be the actual television signal being that it is 3:2 pulldown... streaming it through component cable which is not true 1080p.

Just a couple of things that may be a factor.

Has anyone converted their xdcam files into film? If so, what was the outcome?

Mark Jones · May 20th, 2008, 03:44 PM

I'm glad I saw this thread. I thought I did something wrong with my new EX1 or that my lasik didn't quite take. Even when shooting in 1080p or 1440x1080i I encounter the panning issue. I don't have the same problem with my cheaper Sony V1U HDV camera. I expected more for the bigger price and touted capabilities.

Eric Pascarelli · May 20th, 2008, 03:58 PM

Mark,

I really don't think there's a problem with the camera. There certainly isn't a consensus here on that. Just conjecture.

Mark Jones · May 20th, 2008, 05:03 PM

Then I wonder what settings are making my same movements that I make with the V1U look so bad with the EX1.

May 20th, 2008, 03:44 PM	#28
Mark Jones Tourist Join Date: Mar 2008 Location: Fenton, MO Posts: 2	I'm not crazy after all! I'm glad I saw this thread. I thought I did something wrong with my new EX1 or that my lasik didn't quite take. Even when shooting in 1080p or 1440x1080i I encounter the panning issue. I don't have the same problem with my cheaper Sony V1U HDV camera. I expected more for the bigger price and touted capabilities.

May 19th, 2008, 10:11 AM	#16
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	Nonsense Eric, I've not seen it with any other camera I've used. It obivously is a rolling shutter problem. Varicam doesn't do it, Sony 750 doesn't do it, Sony Z7 doesn't do it, Digibeta cameras don't do it, Canon Ex-1 hi-8 doesn't do it! What you do get from Varicam etc. is a motion blurring but it's subtle. This is just horrible and I think totally unuseable for action shots. Steve

May 19th, 2008, 10:24 AM	#17
Dennis Joseph Major Player Join Date: Jan 2008 Location: Chicago, IL Posts: 206	I am curious if the other Cinealta cameras have a similar judder/flicker effect when doing slow or quick pans. Anyone have any f-900 or F350 footage we can check out? Is there anything that can be done to reduce the flicker? There is a "Flicker Reduce" setting in the menu for 50hz and 60hz but I don't know if it is for that.

May 19th, 2008, 10:27 AM	#18
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	None of the other Cine Alta cameras will do it 'cos none have a rolling shutter. I've used an F900 and it's fine. The only way to reduce is to slow your pans down. Incidentally, the Phantom HD also has a rolling shutter but I've never seen an issue with it, I assume it must just scan the image a lot quicker (it goes upto 1000fps so I gues it needs to, and you pay abut £100,000 for this ability!) Steve

May 19th, 2008, 12:17 PM	#20
Dennis Joseph Major Player Join Date: Jan 2008 Location: Chicago, IL Posts: 206	It flickers even in the slowest movement though.

May 19th, 2008, 12:28 PM	#21
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	Eric, I'm saying that they are 2 different things. Motion blur is always there in progressive, but it's subtle, more subtle the faster the shutter speed. But the effect of the rolling shutter is not subtle, it's ugly. Steve

May 19th, 2008, 01:14 PM	#22
Dennis Joseph Major Player Join Date: Jan 2008 Location: Chicago, IL Posts: 206	Here is an interesting article that will shed some new light on this subject. http://hd24.com/dont_shudder_at_the_judder.htm

May 19th, 2008, 01:53 PM	#24
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	If it's not the rolling shutter then what is it? Varicam/Sony 750 don't do it. They're the cameras I mostly work with, and they don't look like the EX1 does. Steve

May 19th, 2008, 07:37 PM	#26
Dominik Seibold Major Player Join Date: May 2008 Location: Nuremberg, Germany Posts: 285	I noticed, that the vlc-player plays videos more smoothly than the quicktime-player does (I'm using a mac). At 24p the vlc-player produces that typical 3:2-pulldown-look when viewed on a 60Hz-Display (like almost all LCDs do have), but the quicktime-player does it a bit more jerky. Another example is 60p: With vlc it's perfectly smooth, but with quicktime there are periodically emerging kind of synchronization-problems. I wonder how long we have to wait, until apple fixes that. Perhaps somebody has to tell it apple?

May 20th, 2008, 02:41 PM	#27
Dennis Joseph Major Player Join Date: Jan 2008 Location: Chicago, IL Posts: 206	Do most of you play back your footage on a big screen HD tv? Some things that may come into play as far as why there is flicker can be the actual television signal being that it is 3:2 pulldown... streaming it through component cable which is not true 1080p. Just a couple of things that may be a factor. Has anyone converted their xdcam files into film? If so, what was the outcome?

May 20th, 2008, 03:58 PM	#29
Eric Pascarelli Major Player Join Date: Nov 2007 Location: Los Angeles, CA Posts: 498	Mark, I really don't think there's a problem with the camera. There certainly isn't a consensus here on that. Just conjecture.

May 20th, 2008, 05:03 PM	#30
Mark Jones Tourist Join Date: Mar 2008 Location: Fenton, MO Posts: 2	Then I wonder what settings are making my same movements that I make with the V1U look so bad with the EX1.