Strange behaviour in lowlight at DVinfo.net

Eugen Oprina · November 30th, 2005, 12:02 PM

Hi guys,
I am a happy owner of the hd 101. I shot a cople of short films with this camera and I am satisfied what I got for the price. The last one has a low key mood. In post we observed some very strange ghost traces when in low light a caracter dressed in black was moving slowly against a lighter background. There are some traces like the one you see at the lcd (or plasma) screen with a slow refresh rate. The traces ar dark colored and very visible on the light background.It is very annoying. Did you ever encountered something like this? Is it my camera?
At the begining I thought that I used the matrix unproper but I made the test with the standard settings and th ghost traces are there.
I forgot to specify that I shot in DV 25P.
Any ideea?
Eugen

Tim Dashwood · November 30th, 2005, 12:08 PM

This was a problem Tony Wilson and I noticed early on when shooting in DV mode on both 100U and 101E. It appeared that the DV encoder was downstream of the MPEG2 encoder. The mpeg2 encoder shouldn't have even been in the equation when in DV mode!
Tony later received a new 101E camera with newer firmware and the problem was gone. I also observed that the problem disappeared after swapping my 100U camera for a new one. However, I'm not sure what my original firmware version was.

You should contact your dealer and tell him about the problem and request that JVC service have a look at it.

BTW, it has nothing to do with low-light... I observed the "trails" in bright properly exposed daylight. I still have the footage on the server somewhere. I'll find the link.

Eugen Oprina · November 30th, 2005, 12:29 PM

Thank you very much Tim, I'll call the dealer.
By any chance can we upgrade the software without sending the camera to JVC?
Eu

Tim Dashwood · November 30th, 2005, 12:51 PM

Quote:

Originally Posted by Eugen Oprina

Thank you very much Tim, I'll call the dealer.
By any chance can we upgrade the software without sending the camera to JVC?
Eu

Someone over on DVXuser was having a serious VTR problem in his 101E that required a firmware update. They apparently emailed it to him and he updated it himself via the SD card.
However, I believe he was in a remote part of the world, so these were special circumstances.
I would not recommend ever trying to update the firmware yourself. Let JVC do it. Then if they screw it up they can give you a new camera.

Stephen L. Noe · November 30th, 2005, 12:59 PM

This phenomena may explain the massive chromatic abberation "ghost swan" that Barry Green occasionally post. The swan screencap originally shows off the CA problems with the stock lens but the "ghost" CA was amazing and something I've never seen before. The screencap I'm referring to was the very first one I can remember posted for the HD-100.

Tim Dashwood · November 30th, 2005, 01:17 PM

Quote:

Originally Posted by Stephen L. Noe

This phenomena may explain the massive chromatic abberation "ghost swan" that Barry Green occasionally post. The swan screencap originally shows off the CA problems with the stock lens but the "ghost" CA was amazing and something I've never seen before. The screencap I'm referring to was the very first one I can remember posted for the HD-100.

No. It doesn't look anything like CA. It is more like a MPEG artifact on badly compressed DVDs. You may remember the DV clip for way back in August. It was one of the first clips I posted. I'm still trying to find it on my hard drive.

November 30th, 2005, 12:02 PM	#1
Eugen Oprina Major Player Join Date: Aug 2005 Location: Bucharest Romania Posts: 221	Strange behaviour in lowlight Hi guys, I am a happy owner of the hd 101. I shot a cople of short films with this camera and I am satisfied what I got for the price. The last one has a low key mood. In post we observed some very strange ghost traces when in low light a caracter dressed in black was moving slowly against a lighter background. There are some traces like the one you see at the lcd (or plasma) screen with a slow refresh rate. The traces ar dark colored and very visible on the light background.It is very annoying. Did you ever encountered something like this? Is it my camera? At the begining I thought that I used the matrix unproper but I made the test with the standard settings and th ghost traces are there. I forgot to specify that I shot in DV 25P. Any ideea? Eugen

November 30th, 2005, 12:29 PM	#3
Eugen Oprina Major Player Join Date: Aug 2005 Location: Bucharest Romania Posts: 221	Gohst traces Thank you very much Tim, I'll call the dealer. By any chance can we upgrade the software without sending the camera to JVC? Eu

November 30th, 2005, 12:08 PM	#2
Tim Dashwood Wrangler Join Date: Aug 2005 Location: Toronto, ON, Canada Posts: 3,637	This was a problem Tony Wilson and I noticed early on when shooting in DV mode on both 100U and 101E. It appeared that the DV encoder was downstream of the MPEG2 encoder. The mpeg2 encoder shouldn't have even been in the equation when in DV mode! Tony later received a new 101E camera with newer firmware and the problem was gone. I also observed that the problem disappeared after swapping my 100U camera for a new one. However, I'm not sure what my original firmware version was. You should contact your dealer and tell him about the problem and request that JVC service have a look at it. BTW, it has nothing to do with low-light... I observed the "trails" in bright properly exposed daylight. I still have the footage on the server somewhere. I'll find the link.

November 30th, 2005, 12:59 PM	#5
Stephen L. Noe Trustee Join Date: Apr 2005 Location: Chicago Posts: 1,214	This phenomena may explain the massive chromatic abberation "ghost swan" that Barry Green occasionally post. The swan screencap originally shows off the CA problems with the stock lens but the "ghost" CA was amazing and something I've never seen before. The screencap I'm referring to was the very first one I can remember posted for the HD-100.