Image Pulses 2X sec XH A1?

John Huling · December 16th, 2006, 12:07 PM

One only notices the pulsing in the shadow areas not in the highlights. Mossey Lichen laden rocks etc. They are an important part of the scene.

Nathan Brendan Masters · December 16th, 2006, 09:56 PM

Curious, is this a reoccurring issue? Has anyone else had this? I ask because I'm considering this camera (the A1, versus the FX1 which I can get on ebay for under 3g normally) and want to know of any problems with the codec. This is the first I've heard of this making me assume maybe this particular unit is defective but I don't know this for a fact.

-Nate

John Huling · December 17th, 2006, 07:23 AM

Nate
I don't think there is a problem with the camera. It's probably just me "camera operator" issue going on. Or something I am not aware of in the recording process.
That said I took some earlier advice and viewed the footage direct from the camera (HD) to a Sony HD Monitor and there is definately a "pulsing" 2x every sec about in the shadow areas. It looks as if one had slowed an old VHS tape down frame slow motion from the old days. If you look carefully you can see sort of a chromatic shift around details in the shadows. I would like to post the clip but I don't think it would show up on Computer Monitors.

Anyone reading my earlier posts? Before responding. Looking for what I may be doing or since I am still with in the time frame of exchange I could do that. If it truly is a problem. I have not heard of any one else except Holly Rogan that said she may have noticed it. It is a bit like looking at one of those pieces of art for a while to see if you can see the image...once you see it it's easy to notice everytime!

Larry Huntington · December 17th, 2006, 02:01 PM

I had an issue of pulsing much like you describe (for one shot) and I believe it was the image stabilizer that was trying to make suble adjustments combined with shooting a telephoto shot of some trees at dawn. Look at your source tape to see if it's in the tape, then rule out software.

Was the IS turned off?
Did you have Instant IF turned off?

Mark Williams · December 17th, 2006, 04:40 PM

I have had the same problem rarely with same subject matter using my old GL-1. Fast moving water and stationary rocks which would pulse. When I moved over to a Pany DVC30 I no longer had the problem. Of course all was shot in SD when I observed the pulsing on the timeline during playback and on NTSC monitor.

John Huling · December 17th, 2006, 06:08 PM

I am pretty sure everything was full MANUAL. No AF, IS.
I checked the clip directly from the camera to the monitor and it is doing it there. I am waiting to do some more tests and I will report back. Unless anyone has an idea of the cause. Please read this entire thread so I won't have to repeat anything. :) Thanks

Poppe Johansson · December 21st, 2006, 04:15 PM

John, are you talking about this kind of pulsing?
http://rapidshare.com/files/8447054/GOPpulse.mov
This shot is from my "Ice and Water" shots, 4x from trees.
http://www.dvinfo.net/conf/showthread.php?t=82090
Dark areas are pulsing 2x during one second (GOP speed).

At least in this case it's the limit of mpeg2 codec. A picture with fast moving water and still trees, that is very hard for HDV compression. My 720p downconverted (=second generation mpeg) clip shows this very clearly. I can't see it that much in the original FCP captured file, but after I exported shortened 1080i50 clip to Quicktime, pulse became more visible. So after all my "raw" 50i clip isn't 100% raw clip, because I have exported it from FCP and GOP order has changed. So that file is also 2nd generation mpeg2 file.
Better to import with lossless codec, like Bob Hart said. And I still think A1's HDV codec is very good.

But maybe you were talking about something else?

John Huling · December 21st, 2006, 04:33 PM

Poppe
I don't know why guess I am a complete idiot but I can't get those files to down load. I did before on Ice but for some reason they won't now. I keep getting a very long code that has to be entered and most of the edge letters are chopped off. Could you help?
Thanks John

Mark Williams · December 21st, 2006, 04:36 PM

Look carefully at the block of letters. In the background will be 4 or 5 larger grey letters. That is what you need to use. Don't feel bad, I experienced the same thing. The letters are faint grey and are hard to see. Its one of those "where's waldo" things.

Regards,

Poppe Johansson · December 21st, 2006, 04:37 PM

Quote:

Originally Posted by John Huling

Poppe
I don't know why guess I am a complete idiot but I can't get those files to down load. I did before on Ice but for some reason they won't now. I keep getting a very long code that has to be entered and most of the edge letters are chopped off. Could you help?
Thanks John

There should be 4 bigger letters behind those smaller letters. Try adjust your monitor brightness. That could be the reason why you don't see them. They are all black and white.

John Huling · December 21st, 2006, 04:39 PM

Poppe

I can't believe I fiquired it out embarrassed to say I did not realize there were only 4 characters under all those other ones!

Poppe Johansson · December 21st, 2006, 04:42 PM

Quote:

Originally Posted by John Huling

Poppe

I can't believe I fiquired it out embarrassed to say I did not realize there were only 4 characters under all those other ones!

It's like the pulsing, once you see it it's easy to notice everytime! :)

John Huling · December 21st, 2006, 04:46 PM

Well the files would not open but yes once you see it you notice it everytime for sure. I shot some more waterfalls this morning all manual. I used your ice setting. Still get that pulsing 2x second in the rocks shadows especially large smooth areas.

John Huling · December 21st, 2006, 04:50 PM

By the way I shot this footage on 2 XH A1's today just to see if I could repeat the problem. I viewed the footage direct from the cameras to the Monitor HD

Raymond Toussaint · December 21st, 2006, 05:06 PM

Poppe was shooting in '50i' you were shooting in 24F right?

What I see in some other shots is a 'going smooth - going sharp' movement. Specialy on large objects like a velvet black jacket. I saw it on the guitarplayer shot from Iku, during a pan. That was 24F material and it is the normal long GOP behavier. It sees an Iframe and another and renders the inbetweens.

It is something that is HDV-2. Normaly you want notice it, but if you do, you keep on seeing it. The Sony FX1 and Z1 did it more badly.

December 17th, 2006, 04:40 PM	#20
Mark Williams Trustee Join Date: Dec 2002 Location: Deep South, U.S. Posts: 1,526	I have had the same problem rarely with same subject matter using my old GL-1. Fast moving water and stationary rocks which would pulse. When I moved over to a Pany DVC30 I no longer had the problem. Of course all was shot in SD when I observed the pulsing on the timeline during playback and on NTSC monitor. __________________ Mark videos: http://vimeo.com/channels/3523 Stock: http://www.pond5.com/artist/mark29

December 21st, 2006, 04:36 PM	#24
Mark Williams Trustee Join Date: Dec 2002 Location: Deep South, U.S. Posts: 1,526	Look carefully at the block of letters. In the background will be 4 or 5 larger grey letters. That is what you need to use. Don't feel bad, I experienced the same thing. The letters are faint grey and are hard to see. Its one of those "where's waldo" things. Regards, __________________ Mark videos: http://vimeo.com/channels/3523 Stock: http://www.pond5.com/artist/mark29

December 16th, 2006, 12:07 PM	#16
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	One only notices the pulsing in the shadow areas not in the highlights. Mossey Lichen laden rocks etc. They are an important part of the scene.

December 16th, 2006, 09:56 PM	#17
Nathan Brendan Masters Regular Crew Join Date: Feb 2004 Location: Chicago, Il. Posts: 85	Curious, is this a reoccurring issue? Has anyone else had this? I ask because I'm considering this camera (the A1, versus the FX1 which I can get on ebay for under 3g normally) and want to know of any problems with the codec. This is the first I've heard of this making me assume maybe this particular unit is defective but I don't know this for a fact. -Nate

December 17th, 2006, 07:23 AM	#18
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	Nate I don't think there is a problem with the camera. It's probably just me "camera operator" issue going on. Or something I am not aware of in the recording process. That said I took some earlier advice and viewed the footage direct from the camera (HD) to a Sony HD Monitor and there is definately a "pulsing" 2x every sec about in the shadow areas. It looks as if one had slowed an old VHS tape down frame slow motion from the old days. If you look carefully you can see sort of a chromatic shift around details in the shadows. I would like to post the clip but I don't think it would show up on Computer Monitors. Anyone reading my earlier posts? Before responding. Looking for what I may be doing or since I am still with in the time frame of exchange I could do that. If it truly is a problem. I have not heard of any one else except Holly Rogan that said she may have noticed it. It is a bit like looking at one of those pieces of art for a while to see if you can see the image...once you see it it's easy to notice everytime!

December 17th, 2006, 02:01 PM	#19
Larry Huntington Major Player Join Date: Nov 2005 Location: Grass Valley, California Posts: 350	I had an issue of pulsing much like you describe (for one shot) and I believe it was the image stabilizer that was trying to make suble adjustments combined with shooting a telephoto shot of some trees at dawn. Look at your source tape to see if it's in the tape, then rule out software. Was the IS turned off? Did you have Instant IF turned off?

December 17th, 2006, 06:08 PM	#21
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	I am pretty sure everything was full MANUAL. No AF, IS. I checked the clip directly from the camera to the monitor and it is doing it there. I am waiting to do some more tests and I will report back. Unless anyone has an idea of the cause. Please read this entire thread so I won't have to repeat anything. :) Thanks

December 21st, 2006, 04:15 PM	#22
Poppe Johansson Regular Crew Join Date: Jan 2004 Location: Finland Posts: 77	John, are you talking about this kind of pulsing? http://rapidshare.com/files/8447054/GOPpulse.mov This shot is from my "Ice and Water" shots, 4x from trees. http://www.dvinfo.net/conf/showthread.php?t=82090 Dark areas are pulsing 2x during one second (GOP speed). At least in this case it's the limit of mpeg2 codec. A picture with fast moving water and still trees, that is very hard for HDV compression. My 720p downconverted (=second generation mpeg) clip shows this very clearly. I can't see it that much in the original FCP captured file, but after I exported shortened 1080i50 clip to Quicktime, pulse became more visible. So after all my "raw" 50i clip isn't 100% raw clip, because I have exported it from FCP and GOP order has changed. So that file is also 2nd generation mpeg2 file. Better to import with lossless codec, like Bob Hart said. And I still think A1's HDV codec is very good. But maybe you were talking about something else?

December 21st, 2006, 04:33 PM	#23
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	Poppe I don't know why guess I am a complete idiot but I can't get those files to down load. I did before on Ice but for some reason they won't now. I keep getting a very long code that has to be entered and most of the edge letters are chopped off. Could you help? Thanks John

December 21st, 2006, 04:39 PM	#26
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	Poppe I can't believe I fiquired it out embarrassed to say I did not realize there were only 4 characters under all those other ones!

December 21st, 2006, 04:46 PM	#28
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	Well the files would not open but yes once you see it you notice it everytime for sure. I shot some more waterfalls this morning all manual. I used your ice setting. Still get that pulsing 2x second in the rocks shadows especially large smooth areas.

December 21st, 2006, 04:50 PM	#29
John Huling Regular Crew Join Date: Nov 2006 Location: USA Posts: 172	By the way I shot this footage on 2 XH A1's today just to see if I could repeat the problem. I viewed the footage direct from the cameras to the Monitor HD

December 21st, 2006, 05:06 PM	#30
Raymond Toussaint Regular Crew Join Date: Nov 2005 Posts: 173	Poppe was shooting in '50i' you were shooting in 24F right? What I see in some other shots is a 'going smooth - going sharp' movement. Specialy on large objects like a velvet black jacket. I saw it on the guitarplayer shot from Iku, during a pan. That was 24F material and it is the normal long GOP behavier. It sees an Iframe and another and renders the inbetweens. It is something that is HDV-2. Normaly you want notice it, but if you do, you keep on seeing it. The Sony FX1 and Z1 did it more badly.