A Rolling Shutter Issue? at DVinfo.net

Bruce Ostrout · July 29th, 2008, 03:07 PM

I have noticed on a few shoots under flourescent lighting I will get several thick amber colored vertical bars crawling up the screen. On two occasions with a Z1 in a room with flourescent lighting I noticed the WB level pulsing to an amber then blue. At first thought when this occurred on both the Z7 & Z1 I thought it might be the LCD wigging out, but the effect occurs on tape.

I am thinking this issue is the same on both cams but looks like bars on the Z7 because of the rolling shutter. Does anyone else see this and know how to remedy it? Shift to an alternate shutter angle....?

Bill Pryor · July 29th, 2008, 03:11 PM

You're not shooting with the auto shutter and auto white balance on, are you? That might cause the problem.

John Knight · July 29th, 2008, 04:42 PM

Page 71:
Is your FLICKER REDUCE set to "ON"?
Have you tried experimenting with ECS FREQUENCY?

Bruce Ostrout · July 29th, 2008, 05:01 PM

Quote:

Originally Posted by Bill Pryor

You're not shooting with the auto shutter and auto white balance on, are you? That might cause the problem.

No, but I might have been at a shutter speed other than 1/60. I will have to see if i can repro under controlled conditions. I might post some footage.

Bruce Ostrout · July 29th, 2008, 05:03 PM

Quote:

Originally Posted by John Knight

Page 71:
Is your FLICKER REDUCE set to "ON"?
Have you tried experimenting with ECS FREQUENCY?

It is set at whatever the defualt would be. I have not messed with ECS frequency.

Terry Brown · August 3rd, 2008, 04:19 AM

Our Z7 has just gone back under warrenty to have this problem looked at.

We have both a Z7 and S270 and the banding "striation" issue was incredibly strong if we over exposed the aperture to allow for backlight etc. I sent a still to Sony and they said that it does look like the Z7 is faulty.

We could not recreate the exact same problem on the S270, however I was editing some HDV footage this morning, filmed with the S270 under high pressure mercury lighting and there does seem to be an issue.

The aperture was opened slightly to compensate for the fact that the presenters were dressed in white coats with a predominately bright plain background and I have noticed a very faint striation.

It's so faint as to be virtually unnoticable during normal viewing, but if you speed it up you can see bands moving down the image.

Shutter was switched off and I will check about the flicker reduction, I do know that with the Z7 we double checked anything that could affect the shutter.

I will experiment with the S270 and get back with an update.

Laurence Kingston · August 3rd, 2008, 10:57 AM

I have exactly the same effect when I shoot under fluorescent lights and fast forward through the footage. I can't see it though at normal playback speed so I didn't worry about it.

Terry Brown · August 12th, 2008, 02:49 AM

Hi Everyone,

Looks like this was my bad and no one at Sony realised it before asking me to send back.

Probably like many people that have been making videos for many years, I only read the bits of the manual refering to things that were new to me on this camera. I presumed that the shutter was either ON or OFF!

What I missed entirely is that the Z7 does NOT have a Shutter OFF setting, it is either Manual or Automatic.

And because I had the Data Display option in menu switched off there was no indication that the shutter speed was automatic.

So from now on this will always be in manual with the speed set to 50FPS unless we need to adjust it to reduce flicker.

Seems a bit of a silly setting to me (the S270 does have ON, AUTO and OFF settings).

But oh well - I might stop blushing by the end of the day. Other than that the Z7 is awsome!

Michael Poole · November 30th, 2008, 04:55 AM

Could it be rolling shutter a cmos chip problem i have heard that Cmos chip suffer from rolling shutter when paning and change of light more so than 3ccd camera's

Quote:

Originally Posted by Laurence Kingston

I have exactly the same effect when I shoot under fluorescent lights and fast forward through the footage. I can't see it though at normal playback speed so I didn't worry about it.

Aaron Lucas · December 1st, 2008, 06:24 PM

Quote:

Originally Posted by Michael Poole

Could it be rolling shutter a cmos chip problem i have heard that Cmos chip suffer from rolling shutter when paning and change of light more so than 3ccd camera's

Did you read the post above? This issue has nothing to do with the use of rolling shutter on CMOS sensors.

Hugh Mobley · December 4th, 2008, 10:42 AM

If you can get or find the issues of Pro HD magazine,(or HD Pro) it addresses the rolling shutter and three other issues inherent with the cmos chips, its what you have to put up with, its the way the chip analyzes the info, the ccd sees the whole thing, the cmos sees it like you letting down a shutter. thats it, I believe it was the August and October issue, there are also white papers , go to DALSA and fish thru for the tech stuff, its there also, this company was instrumental in the design. I had to read it twice (my friend let me read his) the chips provide things the ccd doesn't, and basically the Ex1/3 could have never been made without them, too much heat. so you get what you get. All high end cameras use the ccd for now, and the cmos is cheaper to make I believe

Laurence Kingston · December 4th, 2008, 12:00 PM

I just shot some Z7 24p footage under mercury vapors. The banding was very pronounced.

Scott Caplan · February 16th, 2009, 07:18 PM

Is there a way to correct the banding in post? I thought the fluorescents in one location we shot at were high-frequency, but they were not. Plus I assumed the shutter was set at 1/60, and it was not. I'd like to avoid having to reshoot this scene, and wondered if there was a plug-in to correct this in post or not?

Thanks!

Scott

July 29th, 2008, 03:07 PM	#1
Bruce Ostrout Regular Crew Join Date: Jun 2006 Location: Jacksonville Fl Posts: 107	A Rolling Shutter Issue? I have noticed on a few shoots under flourescent lighting I will get several thick amber colored vertical bars crawling up the screen. On two occasions with a Z1 in a room with flourescent lighting I noticed the WB level pulsing to an amber then blue. At first thought when this occurred on both the Z7 & Z1 I thought it might be the LCD wigging out, but the effect occurs on tape. I am thinking this issue is the same on both cams but looks like bars on the Z7 because of the rolling shutter. Does anyone else see this and know how to remedy it? Shift to an alternate shutter angle....?

July 29th, 2008, 04:42 PM	#3
John Knight Major Player Join Date: May 2008 Location: Auckland, New Zealand Posts: 588	Page 71: Is your FLICKER REDUCE set to "ON"? Have you tried experimenting with ECS FREQUENCY? __________________ Over 28 years watching TV

August 3rd, 2008, 04:19 AM	#6
Terry Brown Tourist Join Date: Jul 2008 Location: UK Posts: 3	Z7 Shutter Issue Our Z7 has just gone back under warrenty to have this problem looked at. We have both a Z7 and S270 and the banding "striation" issue was incredibly strong if we over exposed the aperture to allow for backlight etc. I sent a still to Sony and they said that it does look like the Z7 is faulty. We could not recreate the exact same problem on the S270, however I was editing some HDV footage this morning, filmed with the S270 under high pressure mercury lighting and there does seem to be an issue. The aperture was opened slightly to compensate for the fact that the presenters were dressed in white coats with a predominately bright plain background and I have noticed a very faint striation. It's so faint as to be virtually unnoticable during normal viewing, but if you speed it up you can see bands moving down the image. Shutter was switched off and I will check about the flicker reduction, I do know that with the Z7 we double checked anything that could affect the shutter. I will experiment with the S270 and get back with an update.

August 12th, 2008, 02:49 AM	#8
Terry Brown Tourist Join Date: Jul 2008 Location: UK Posts: 3	Oh Boy feeling like a fool Hi Everyone, Looks like this was my bad and no one at Sony realised it before asking me to send back. Probably like many people that have been making videos for many years, I only read the bits of the manual refering to things that were new to me on this camera. I presumed that the shutter was either ON or OFF! What I missed entirely is that the Z7 does NOT have a Shutter OFF setting, it is either Manual or Automatic. And because I had the Data Display option in menu switched off there was no indication that the shutter speed was automatic. So from now on this will always be in manual with the speed set to 50FPS unless we need to adjust it to reduce flicker. Seems a bit of a silly setting to me (the S270 does have ON, AUTO and OFF settings). But oh well - I might stop blushing by the end of the day. Other than that the Z7 is awsome!

December 4th, 2008, 10:42 AM	#11
Hugh Mobley Major Player Join Date: Nov 2006 Location: Placentia, Calif Posts: 549	If you can get or find the issues of Pro HD magazine,(or HD Pro) it addresses the rolling shutter and three other issues inherent with the cmos chips, its what you have to put up with, its the way the chip analyzes the info, the ccd sees the whole thing, the cmos sees it like you letting down a shutter. thats it, I believe it was the August and October issue, there are also white papers , go to DALSA and fish thru for the tech stuff, its there also, this company was instrumental in the design. I had to read it twice (my friend let me read his) the chips provide things the ccd doesn't, and basically the Ex1/3 could have never been made without them, too much heat. so you get what you get. All high end cameras use the ccd for now, and the cmos is cheaper to make I believe __________________ Hugh Mobley www.petplanetvideos.com http://exposureroom.com/members/hmobley.aspx/

July 29th, 2008, 03:11 PM	#2
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	You're not shooting with the auto shutter and auto white balance on, are you? That might cause the problem.

August 3rd, 2008, 10:57 AM	#7
Laurence Kingston Major Player Join Date: Aug 2004 Location: Clermont, FL. Posts: 941	I have exactly the same effect when I shoot under fluorescent lights and fast forward through the footage. I can't see it though at normal playback speed so I didn't worry about it.

December 4th, 2008, 12:00 PM	#12
Laurence Kingston Major Player Join Date: Aug 2004 Location: Clermont, FL. Posts: 941	I just shot some Z7 24p footage under mercury vapors. The banding was very pronounced.

February 16th, 2009, 07:18 PM	#13
Scott Caplan Regular Crew Join Date: Aug 2008 Location: Kansas City (NJ/NYC transplant) Posts: 81	Is there a way to correct the banding in post? I thought the fluorescents in one location we shot at were high-frequency, but they were not. Plus I assumed the shutter was set at 1/60, and it was not. I'd like to avoid having to reshoot this scene, and wondered if there was a plug-in to correct this in post or not? Thanks! Scott