Error in 1080 24PA mode

B

Bob Gruen

Well-known member
I thought this might be an NLE problem, but now I don't think so.

I'm in the middle of doing a film-out test of my workflow and I've run into a big problem. There is a pink line in every three frames at the bottom of the image. It is on the very bottom on the left side then jumps up a pixel or two on the right. It appears on NLE playback and on exported material, but not in frame by frame inspection in Avid.

pinkline.JPG


My workflow is as follows:
  • HVX set to 1080i / 24PA
  • Recording in DV Rack making QT Avid files (which cannot be viewed with QT for some reason)
  • Import into Avid, DNxHD 175
  • Export as MOV encoded with DNxHD 175, 115, or same as source
I think I may have seen this line twice before. First, when the camera is set up to 1080i / 24PA it flashes the same / similar line on my 1080i television. When thoff did a test pulldown removal for me using the Serious Magic batch converter the pink line disappeared. So I assumed it was an artifact in the garbage frame that the Advanced Pulldown creates. Next when I bought DVRack and did not update it it had a bug that removed the wrong frame during advanced pulldown removal. The line showed up in this situation on the interlaced frame. I thougt that this verified my theory about it being part of the garbage frame, so I didn't worry about it.

So now that I am ready to send a file off to be printed the line has reappeared, maybe... I'm not sure if it is the same line or if it is a similar looking error in the data stream that Avid can correct on scene by scene inspection but not 'on the fly'... Now I am wondering if there is something wrong with my camera, although like I stated earlier the flaw does not show up when I view the footage frame by frame. I guess it could also be part of the garbage frame and DV Rack is not dealing with it properly.

Any thoughts or ideas? I want to get this exported to send it to DVFilm for a test printing. Any help or suggestions would be appreciated.

Bob
 
Can you export a few frames of the original recording and post it? I'm trying to see if this is a display-only problem with your video drivers.

I've been using DV Rack HD since it came out, and haven't run into this. However, I also don't use Avid or record QT Avid files, but DV Rack doesn't handle the encoding of the file, it just dumps the data from the camera into the container file, so it can't be adding the pink line at the bottom to the output.
 
I don't think the pulldown is being removed by
recording through DV rack.
What is your sequence set to?
Inspect the file in QuickTime outside of your NLE.
 
DV Rack can remove the duplicate frames -- that is controlled through the DV TYPE setting in the menu. If you set it to TYPE 1, the duplicate frames are removed; if you set it to TYPE 2, they are recorded to disk.

Bob, how did you wind up with a MXF file? DV Rack would have recorded a AVI or MOV. I loaded the file into Edius and don't see a pink line at the bottom (or the top for that matter, my guess is you used a DOF adapter).

Either the problem is with your display driver, or it happens in post when the image is flipped. I added the Mirror video filter in Edius to flip the image right-side-up, and that didn't add pink lines either.
 
Hi,

I think they have send the inquiry back to the factory and from what I hear, they are awaiting a reply from the factory. I suggest that you keep in touch with Paco and Hector as they will be who will help you solve the issue.

All the best,

Jan
 
I have had a similar problem with 1080i24pA only my line is in the top left and it seems to flex and shift as described above. I use a MacBook Pro with FCP 5.1.4. Any thoughts would be much appreciated on solving the issue.

Any pro's out there heard of this issue and know a solution? It isn't vital for me but it is annoying to have to increase the scale of all my 1080i24pA clips to cover up the problem.
 
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