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  #1  
08-11-2013, 02:17 PM
yellow_inspir yellow_inspir is offline
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Hello all,

I am new to the forum but I have a few years of consumer-level experience with VHS to digital transfers.

I have recently taken on a project to digitize a few dozen SVHS tapes of microscopy data recorded in the 1990s.

Currently using a JVC SR-S365U on loan from the AV department. It seems to be working fine aside from the very serious problem of persistent "streaks" or "blips" appearing in the center of the image no matter what is done with the tracking settings. These artifacts are not on the tapes themselves, as they are absent when the tapes are played in lower-end VCRs. Should I attempt to clean the heads? I don't think this deck has been maintained much, if ever, during its probably very active service life.

Furthermore, the project manager would like a capture card solution that can encode the SVHS output to .mp4 "on-the-fly" in order to avoid compressing later due to time limitations.

Can any of the cards suggested here: Best ATI All In Wonder card alternatives, to transfer tapes to digital? accomplish this?

Finally, do I really need a TBC for this job? The tapes don't appear to have much jumpiness but I do want them to come out as optimally as possible.

I have a budget of a few hundred dollars for this job. Any suggestions at all would be most appreciated. Thank you for reading my thread and best regards!
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  #2  
08-11-2013, 04:05 PM
volksjager volksjager is offline
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there is probably something wrong with that SR-S365U
try cleaning it, if it doesn't help buy a better deck
do you know what deck they where made on?
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  #3  
08-12-2013, 10:53 PM
yellow_inspir yellow_inspir is offline
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Thanks for your interest in helping me out, volksjager.

Unfortunately, it would be impossible to track down what machine was used to make these tapes.

What I do know is they were transferred from U-Matic to SVHS at a research institution in France.
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08-14-2013, 11:29 AM
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lordsmurf lordsmurf is online now
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Quote:
Furthermore, the project manager would like a capture card solution that can encode the SVHS output to .mp4 "on-the-fly" in order to avoid compressing later due to time limitations.
This isn't going to look good at all.
It needs a quality deinterlace, and that's going to require post-capture processing.

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- For sale in the marketplace: TBCs, workflows, capture cards, VCRs
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  #5  
08-24-2013, 07:18 PM
yellow_inspir yellow_inspir is offline
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Hi, lordsmurf. Thanks for the input. I figured that good post-processing was necessary. The priority is definitely to capture and preserve as much of the best quality video as possible so speeding up the process is a bad idea.

The following screen shots were taken from some .avis captured uncompressed using Virtualdub with a Pinnacle s-video PCI card and JVC SRS365U in AUTO and SVHS mode.

JVC_SRS365U_SVHS_AUTO.jpg

This a screen cap of part of the video. From what I have read about it online, the image seems to exhibit the infamous JVC "comet" issue.

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Here is another screen cap of the same tape taken immediately after a cleaning of the video heads using a PreSat 99% IPA-soaked foam swab. The comets disappeared only to return almost immediately after this video was taken. My guess is that the static electricity accumulated between the upper and lower drums of the video head that is said to cause this issue was temporarily dissipated during the cleaning. It only took minutes of operation for the static to return.

JVC_SRS365U_SVHS_AUTO_after_cleaning.jpg

For comparison, here is a screen cap from a video of the same tape recorded from a JVC HRS5901U in SVHS and AUTO mode. I can immediately see the difference in quality between the VCRs.

So now I want to try to repair the JVC SRS365U. From the service manual, I see the static brush assembly pdm4440a is the part in question. It seems to be available from many suppliers online for about $6.05. Will a replacement brush solve the problem at least for an extended period of time sufficient to capture these tapes? Maybe cleaning the existing brush will suffice?

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JVC_HRS5901U_SVHS_AUTO.jpg

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ScreenHunter_67 Aug. 24 17.05.jpg

I see that a realignment is necessary after disassembling the video head. I have experience with an oscilloscope and access to the necessary cables. However, I have no idea how to obtain this MHP alignment tape. It doesn't seem to be sold anywhere.


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