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Posted: 26 Jan 2020, 21:18 

Gosh, this is technical. I've never used Avisynth, so I'm going to have to look all this up. It looks complicated.
It is, but here's a primer: http://macilatthefront.blogspot.com/2018/09/tutorial-4-sd-to-hd-revisited.html

1. What is this blur? Is that just an artifact from working with such an old format?
It's a common artifact of high-contrast transitions that occur horizontally; it's an artifact of analog video. One longer explanation of this is in the Video Essentials laserdisc tutorial material, IIRC. It affects both luma and chroma, which is why you can see this kind of blurring sometimes in the NTSC SMPTE color bars test pattern even though the luma is constant in those transition areas.

I think that artifact is in the source material. It was definitely not introduced by my software process, although it's possible it might have been exasperated during the capture process.

2. Is this a levels thing? Can you explain what this means?
Analog video goes from 0 to 100 IRE. For North American NTSC broadcasts, 7.5 IRE is considered the displayable level of black; for Japan, they used 0 IRE. When I started capturing laserdisc, I used to capture with 7.5 IRE as the black level, but I found that mixed-content discs (like Mind's Eye, and some documentaries) would mix these standards and the 0 IRE content would have severely clipped blacks. So, I now don't assume anything, and capture with 0 IRE so that I can adjust it later using the waveform monitor display in Premiere, sometimes clip by clip if necessary. Even if the disc is mastered properly and correctly, I still do this, just because I want fine control over the black level.

100 IRE is too intense and caused blooming for large areas of white on older sets, so the general NTSC standard for white is 80 IRE.

The final output of my adjustments translate black->100 IRE as 0-1024 RGB (1024 being the highest value in a 10-bit colorspace). Some people argue that 80 IRE should be used as "full white" but I have seem clipping and loss of detail when I do that, so I follow the standard. As a result, sometimes the output is a hair dimmer than what people are expecting, but at least nothing clips. Until I have an HDR process, allowing 100 IRE material to be "whiter than white" is not feasible for me. I have an OLED that can do HDR and DolbyVision, but Premiere Pro's HDR workflow still leaves a lot to be desired, sadly.

3. I realize you are saying 10-bit is great, and as an editor myself, you are absolutely right. However, I don't want to spend more money than I already have on this. Do you think my Elgato Game Capture HD would suffice? I think that only does 8-bit 4:2:0.
No. See next answer:

4. If I do want to upgrade in the future, is this older version of the Blackmagic Intensity Pro still 10 bit? https://smile.amazon.com/dp/B001CN9GEA/ref=nav_timeline_asin?_encoding=UTF8&psc=1
That is exactly the hardware I'm using. It works on an i7-8700k system with two GTX 1080 ti cards, taking up the third and last slot on the motherboard. With the correct older version of the software, I've had no issues, although it took some adjustment to handle 486 total lines instead of 480 (I just crop the two 2 and bottom 4 in the final avisynth output stage).

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Posted: 09 Feb 2020, 05:04 


Do me favor - discuss your technical questions in PM, nothing personal.

That's the very definition of "personal".

If this thread is specifically about " mclaus projects only Laserdisc digitalization and restoration", then you should change the title of the thread. The title of the thread suggests that it is a discussion about all Laserdisc transfers and restoration, and technical details are part of that discussion.


How do you interpret the footage in Premiere (or in my case, After Effects)? Upper field first, lower field first, or off so it shows both fields at once? Do you use any pull down settings?

The 525i30 footage captured from the BMIP is lower-field-first.
Pulldown settings are for turning telecined film footage back into 24p, but only use this for material you are 100% sure is only film. Some music videos have film elements with video effects or transitions, so pulldown isn't appropriate for those.

BTW, I wouldn't try to use After Effects as a video editor. If you're working with footage > 10 minutes long, it should be in Premiere.

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Posted: 02 Mar 2020, 00:04 

I don't know what version of avisynth+ that is; I'm using 20190829 r29xx (you have to get it from github, https://github.com/pinterf/AviSynthPlus/tree/MT I think). As for ffaudiosource/ffvideosource, I'm using FFMS2_2.23.1_MSVC_FFMPEG_4.2.2, also from github: https://github.com/FFMS/ffms2/releases

Here's what my scripts look like:

# FFMS is the only loader guaranteed to pass through 10- to 16-bit footage:
X = "computer dreams finished.avi"
A = FFAudioSource(X)
V = FFVideoSource(X)
AudioDub(V, A)
# produces YUV422P10 after loading v210 input

To start troubleshooting, do only the above, then info(), and see what colorspace is reported.

Keep in mind that avisynth troubleshooting is beyond the scope of this specific thread; there are years of threads about that over at doom9.org if you need targeted help.
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