digitalFAQ.com Forum

digitalFAQ.com Forum (https://www.digitalfaq.com/forum/)
-   Capture, Record, Transfer (https://www.digitalfaq.com/forum/video-capture/)
-   -   What is causing these capture quality issues? (https://www.digitalfaq.com/forum/video-capture/8958-causing-capture-quality.html)

Upandrunning 08-31-2018 02:30 PM

What is causing these capture quality issues?
 
1 Attachment(s)
Hi All

Just wondering if anyone knows what is causing the following capture quality issues in the attached image of a conversion I just did?

You will see there is a blury horizontal line across the bottom of the screen.

There is also two veritcal black bars up each side of the frame which erodes into the image.

Anyone have any ideas why this is so and how to get rid of it?

Also does anyone have any ideas on how I can get a better conversion of this video that is clearerer and sharperer as it seems too blury and low qaulity. Any tips will be helpful.

My workflow

Late 1980s commercial NTSC VHS tape ---- JVC HR-S7600AM VCR ---- BlackMagic Intensitry Pro 4K PCI-E ---- Windows 10 ---- BlackMagic Media Express -- capturing and saving at 525i59 NTSC 8-bit YUV Avi file.

Thanks :question:

lordsmurf 08-31-2018 02:36 PM

Post a clip, or at least a screenshot.

Right now, it just sounds like standard overscan noise: head-switching, pillars.

That's not a suggested workflow, due to Blackmagic issues, but I don't want to jump straight to blaming it just yet. Need to see exactly what you're talking about.

If it's just the one tapes, obviously the root cause is the tape. But now the question is did the errors cascade into the signal, and did that signal mess with other workflow hardware.

Upandrunning 08-31-2018 04:24 PM

1 Attachment(s)
Hi Lord Smurf

I attached a .png file of the digital conversion in my above message titled "Conversion.png" (unless I stuffed it?) but have reattached it again for this response.

I obtain this error across various tapes, especially the blurring horizontal line at the bottom of the screen.

I bought that ATI 600 USB capture device from you via this site, and it arrived to me in Australia, but it doesn't work with Windows 10 so I went back to the BlackMagic PCI-E card.

Thanks for your help

hodgey 08-31-2018 04:41 PM

The blurred horizontal line is head switching noise, it's always going to be there on VHS captures.

As you have a JVC machine, check the "Picture Control" setting in the menu, if it's set to SOFT or SHARP settings there image will be overly blurred.

Also note that the the video in the preview window in Blackmagic Express has some deinterlacing applied to it (don't remember if it can be turned off or not), so check the actual recording rather than the preview to see what the capture actually looks like (or consider using VirtualDub for more control and to be able to use lossless video compression).

Surprised you're not getting black frames with the Blackmagic card, maybe this particular one is different, or maybe they updated the firmware or drivers to fix the issue?

Upandrunning 09-01-2018 02:55 PM

Thanks for your response Hodgey

I turned the JVC picture control off. I think it did something. Can't quite tell though as my eyes aren't trained well enough yet to spot the quality differences.

In relation to deinterlacing, yes there is some. After I recorded the AVI file with the BlackMagic PCI-E and Media Express software, I then imported the AVI file it into Adobe Premiere and deinterlaced it, set the white balance with their selector tool, cut the beginning and ends of the vid, and then exported it as AVI lossless again. I thought de-interlacing is a good thing you so you don't see the lines anymore?

Also the AVI files with Black Magic are massive, depending on VHS tape length, can easily get over 100 GB for a file. I assume that is an indication of meaning lossless.

I am not aware of VirtualDub. I will research it.

Not sure what you mean by black frames? Do you mean lost video frames where the video and audio eventually get out of sync? I had the issue with a different vhs tape pretty the other day and had to cut the audio half way through in Premiere and move it back half a second or so along the timeline so that it matched the video again. Therefore halfway through the video is a short silent part so it can resync again. Not sure if that makes sense?

Cheers

Eric-Jan 09-02-2018 08:27 AM

When capturing you see a lot more, which computer screens call overscan, yes, any BlackMagic Design device needs a clean input signal, a Time Base Corrector between VCR and capture device will help, but not for everything, a consumer VCR with build in stabilization, can give also good results, Most VCR-DVD combo's will have this already build-in for obvious reasons.


All times are GMT -5. The time now is 02:23 PM

Site design, images and content © 2002-2024 The Digital FAQ, www.digitalFAQ.com
Forum Software by vBulletin · Copyright © 2024 Jelsoft Enterprises Ltd.