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  #21  
12-13-2011, 11:36 PM
robjv1 robjv1 is offline
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Originally Posted by sanlyn View Post
It's amazing how that 20-pixel border of "head switching noise" disappears when I remove the proc amp.
While clearly some of the 'noise' here is caused by the proc-amp, don't virtually all VHS and SVHS VCRs have some head switching noise at the bottom of the frame? The smallest I've seen is on GShelly's (on Videohelp) JVC SR-W5U in the screenshots he posted. I've never seen a VCR with none though. Any models that you know of?

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Originally Posted by sanlyn View Post
I realize that many TVs crop the display and won't you set up for the full image. I don't watch those TVs. I find that doing so is visually annoying. I think you might have bypassed looking at the sample captures made without the problematic proc amp on some protected tapes. Why maim a good image? All I had to do was find another way to capture without the Macrovision side effects. The proc amp is less fiddly, but not if I have to cut up the film directors' work.
I know by default that monitors don't have overscan, but I thought the majority of the TV sets out there (including LCD, plasma) applied some overscan to the image. I actually have a couple of HD CRTs (Sony KD-XBR910 and KD-XBR960) which have a noticeable overscan but it can be dialed down to 0 if need be in the service menus.
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  #22  
12-14-2011, 08:21 AM
sanlyn sanlyn is offline
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Quote:
Originally Posted by robjv1 View Post
While clearly some of the 'noise' here is caused by the proc-amp, don't virtually all VHS and SVHS VCRs have some head switching noise at the bottom of the frame? The smallest I've seen is on GShelly's (on Videohelp) JVC SR-W5U in the screenshots he posted. I've never seen a VCR with none though. Any models that you know of?
I didn't say there was no pulse sync or switching noise in the VCR's I used. The captures posted here show 4 pixels of that noise at the bottom of the frame on all tapes:
http://www.digitalfaq.com/forum/18279-post9.html
http://www.digitalfaq.com/forum/18300-post11.html

My deceased JVC 7600 produced a similar frame. As I said, there's no image down there. I mask it with RGB 12 black in TMPGenc or Avisynth. I don't see 4 pixels as being that much of a problem. But 20 pixels, yes. I have one Panny VCR I don't use any more that has a lot of noise down there, but I don't think it was properly aligned and haven't found a tech who would (or could) check it. My experience with most (but not all) a/v techs is that they're clueless when it comes to PQ.

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Originally Posted by robjv1 View Post
I know by default that monitors don't have overscan, but I thought the majority of the TV sets out there (including LCD, plasma) applied some overscan to the image. I actually have a couple of HD CRTs (Sony KD-XBR910 and KD-XBR960) which have a noticeable overscan but it can be dialed down to 0 if need be in the service menus.
My old HD CRT bit the dust some time back, but I did adjust for full frame. I did that with my old SD CRT in the service menu, but still lost about 4 pixels anyway -- better than the default, though. I do the same for my SONY LCD and Samsung plasma. By default the latter two used a bit of overscan. The SONY does it on all input sources, the Samsung didn't do it with DVD or BluRay but it cut off a bit with VCR input (I wonder why?).

I belong to a local videophile/classic film club with about a dozen members. All of them raise hell when they see overscan. I recall some of us paid good cash to attend a silent-film festival in Connecticut. The first thing we noticed was that the projector was set to expand the image several inches beyond the size of the screen. One member demanded his money back; the manager refused, had no idea what the guy was talking about, so the member walked out. None of us stayed for more than a couple of films.

What I'm talking about is strictly a personal preference. In my PC repair business I visit many homes and see SD material stretched on HDTV's everywhere. The viewers don't see any difference, and I don't say anything (I have other work to do, anyway, and how they watch TV is none of my business). It's just a personal "thing".
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  #23  
12-15-2011, 09:19 PM
robjv1 robjv1 is offline
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Quote:
Originally Posted by sanlyn View Post
I belong to a local videophile/classic film club with about a dozen members. All of them raise hell when they see overscan. I recall some of us paid good cash to attend a silent-film festival in Connecticut. The first thing we noticed was that the projector was set to expand the image several inches beyond the size of the screen. One member demanded his money back; the manager refused, had no idea what the guy was talking about, so the member walked out. None of us stayed for more than a couple of films.

What I'm talking about is strictly a personal preference. In my PC repair business I visit many homes and see SD material stretched on HDTV's everywhere. The viewers don't see any difference, and I don't say anything (I have other work to do, anyway, and how they watch TV is none of my business). It's just a personal "thing".
Nothing wrong with that at all -- lots of footage is precious and should be maintained at the highest standard possible. I can understand where you are coming from and your expectations for the premium equipment you use.

On a bit of a side note -- how prevalent was Macrovision in the heyday of the VHS business? I assume it only impacted the major studio films due to the fee of using the protection and the potential for lost revenue for the piracy of the film, was it pretty much all of them? I don't work with a big amount of commercial sources, but I do know for the few I do have, most of the non-independent films have the protection scheme.
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  #24  
12-15-2011, 09:42 PM
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Macrovision was not the only anti-copy system in use. There were a number of nasty signal injections that were known to massively screw up how tapes played, even with a basic VCR > TV playback. Disney tapes and Lucasfilm tapes were among the worst. The Young Indiana Jones Chronicles (movie version VHS releases, circa mid/late 1990s) stands out as a great example of tapes that would actually get worse when passed through a TBC. They played with errors directly to a TV.

--

As a photographer, the preset size of film is already limiting, and I almost always crop images to the perfect size. Frames are built for my images, I don't shoot images for frames. I have frames custom built, I don't use ready-make cheap frames from Hobby Lobby.

Videographers are forced to work within a preset space, too. But unfortunately, they don't really have the luxury of cropping. I would not 100% assume the crop is what a director necessarily wanted. Sometimes it's just "close enough" to convey the story (or art, if that be the case). Cropping a few more pixels is honestly still within that "close enough" territory. Not that it should be done if it can be avoided, but sometimes your hand gets forced.

I often have to crop 4:3 to 16:9, when the tape has catastrophic tracking errors. You work with remaining good signal, to produce the most enjoyable image and audio for the viewer (aka out clients). It's a necessary evil.

I can understand the pursuit of perfection, but sometimes it's just not feasible.

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  #25  
12-15-2011, 10:01 PM
robjv1 robjv1 is offline
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^ Interesting! I was always under the impression that Macrovision solely controlled the market and licensed it out to all of those companies.
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  #26  
12-15-2011, 10:13 PM
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Quote:
Originally Posted by robjv1 View Post
under the impression that Macrovision solely controlled the market
Eventually, yes, due to mergers and acquisitions (M&A).

To quickly swipe a Wikipedia quote:

Companies such as Macrovision and Dwight Cavendish provided schemes to videotape publishers making copies unusable if they were created with a normal VCR. All major videotape duplicators licensed Macrovision or similar technologies to copy protect video cassettes for their clients or themselves. Starting in 1985 with the video release of "The Cotton Club", Macrovision has licensed to publishers a technology that exploits the automatic gain control feature of VCRs by adding pulses to the vertical blanking sync signal.[6] These pulses do not affect the image a consumer sees on his TV, but do confuse the recording-level circuitry of consumer VCRs. This technology, which is aided by U.S. legislation mandating the presence of automatic gain-control circuitry in VCRs, is said to "plug the analog hole" and make VCR-to-VCR copies impossible, although an inexpensive circuit is widely available that will defeat the protection by removing the pulses. Macrovision has patented methods of defeating copy prevention, giving it a more straightforward basis to shut down manufacture of any device that descrambles it than often exists in the DRM world.

Note the keyword: major. A number of operations have always wanted to do things their own way, so they opted for small lesser-known methods, or developed in-house methods. I sometimes think Macrovision was altered or added to other methods, to create some of the messes I've observed through the years. (And I'd bet it wasn't within the user agreement, if it did happen.)

Most dedicated fans will buy a newer version, if available and unbutchered (no "improvements" or content edits). The best method for studios/producers to protect their income was to just provide quality releases for fair prices, as demanded by their customer base. (For the most part, that's happened, though it took a while. Forced copy "protection" was never so required as to violate the specs of how VCRs produce good images. You can mostly thank the now deceased Jack Valenti for that one.) Sadly, a few odds and ends slipped through the cracks, so we have threads like this. "Help me preserve my favorite movie that's not available in any other format." A reasonable request, I'd say.

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  #27  
12-16-2011, 07:32 AM
sanlyn sanlyn is offline
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Very informative. I'm not surprised that copy protection has many forms. I have a couple of tapes that uniformly display at least one variation: the disturbance at the bottom of the image gradually fades, although it takes about 45 minutes -- halfway thru the tape -- to disappear. At the same time, color and noise gradually improve as well. At first there's a lot of color noise, low saturation, slow but visible color tone shifts. On other tapes, there's a slow but detectable variation in brightness; this also disappears about halfway through the tapes.

Many of these effects are seen in normal playback, but the odd problems with frame borders appear only when I use a proc amp. Sign Video grays out the the bottom 20 pixels, but the BVP-4 does weird things with left and right borders, placing a stripe one one or on both, or distorting the right border video. Why these effects are there with a proc amp, I have no idea. My AVT-8710 has basic proc amp controls, certainly not as sophisticated as the PA-100 or BVP-4, but the AVT-8710 doesn't display those border effects. Other effects on color and brightness are always there, but they look a bit worse without the line-TBC or frame-TBC.

Whatever the cause of the effects with proc amps, it's beyond my expertise. But at least I found a workaround: remove the proc amp and use something nearly as effective but more fiddly and inconvenient. I rely heavily on the PA-100 luma meter; without it, I have to use a VirtualDub histogram and jockey back and forth between viewing settings and contrast/brightness controls, etc., and color balancing on bad video is just more bothersome. But, as long as the workaround works . . .that's what I'll have to tolerate.
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  #28  
12-16-2011, 06:17 PM
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Quote:
Originally Posted by sanlyn View Post
V but the BVP-4 does weird things with left and right borders, placing a stripe one one or on both, or distorting the right border video. Why these effects are there with a proc amp, I have no idea.
In the case of the BVP-4, it's really nothing more than an engineering flaw. It varies highly between the models. One of the BVP's here has almost zero in-image bordering. Others, however, can eat up almost half of the "safely off screen" overscan area.

Quote:
My AVT-8710 has basic proc amp controls, certainly not as sophisticated as the PA-100 or BVP-4, but the AVT-8710 doesn't display those border effects. Other effects on color and brightness are always there, but they look a bit worse without the line-TBC or frame-TBC.
I've never been comfortable referring to the AVT-8710's color controls as being anything related to a "proc amp". But I lack a good description. The video is not passed through any degree of complex circuits, so these are very basic adjustments.

Quote:
But at least I found a workaround: remove the proc amp and use something nearly as effective but more fiddly and inconvenient. I rely heavily on the PA-100 luma meter; without it, I have to use a VirtualDub histogram and jockey back and forth between viewing settings and contrast/brightness controls, etc., and color balancing on bad video is just more bothersome. But, as long as the workaround works . . .that's what I'll have to tolerate.
While VirtualDub is good (the ColorMill 2 plugin especially), you'd probably like Adobe Premiere Pro CS4 or CS5 much better. The color controls are quite advanced, Photoshop-like (not surprising considering both are Adobe products, and the software has lots of crosstalk of features / interoperability between programs).

Give that a try sometime, if you have access to Premiere Pro.

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  #29  
12-16-2011, 11:02 PM
sanlyn sanlyn is offline
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I don't expect much from the AVT-8710 image controls. Bright/Contrast is all I attempt to control there.

Unfortunately Premiere is unsuitable for the way I capture. I see no reason to tolerate design mistakes like 64-bit Vista/Win7. My captures are to AVI/YUY2, most of the initial luma and some very basic color correction are done with AviSynth, usually to avoid crushed blacks and blown out brights. A lot of tape damage gets fixed in YUV or YCbCr first, then I move to RGB with VirtualDub and After Effects CS3 for most of the color work. In fact AE is difficult to learn, but I'm finding it essential for correcting many VHS damage problems. I'm not knocking Premiere. It's great stuff. But with VHS, a lot has to be fixed before it gets to Premiere or AE.
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  #30  
12-17-2011, 12:58 AM
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I actually ran into an early copy protection system on a Disney Betamax movie, I think it was called CopyGuard. Most capture cards don't pick it up, but it did something funky with the vertical blanking interval. My Panasonic plasma TV showed the video with the VBI in the center of the screen (like the vertical hold on a CRT was stuck), so I saw the bottom half of the frame, black strip (VBI) and then the top half of the frame. Running that video though a TBC completely fixed the problem. Another cheap trick was to turn on the digital effects on my SL-HF860D deck, running any video though its frame buffer completely regenerated video sync like a TBC.

I also had some interesting problems with Macrovision VHS tapes that were dubbed to Betamax. Betamax was pretty immune to Macrovision due to how its automatic gain control worked, so dubbing was possible. What I found out is that there was still residual traces of Macrovision on those tapes (1990s Disney, go figure), it caused my AVT-8710 to jack up the contrast and/or brightness and completely blow out the whites in the video.
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  #31  
12-17-2011, 07:23 AM
sanlyn sanlyn is offline
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Amazing, the number of ways engineers can work Frankenstein effects on media. With so many hobbyists working around these tricks, the industry has finally hit on new ways to prevent private use: discontinue the input/output connections on incoming and playing components (cable boxes, TV, etc.), stop making anything that can make copies of anything, and screw up a/v with weird tricks like using Ethernet twisted-pair wire to make something that they misnamed "HDMI". It's a wonder anything transmits coherent images or audio, whether analog or digital. Back in the 1920's and 1930's engineers figured out how to screw up analog tv with a crippled NTSC that never improved very much for nearly a century. They replace analog chaos with digital logic and discover they created their own nightmare (as usual).

Maybe these guys oughtta read the original Frankenstein. There are reasons why they say the book was better than the movie.

Yes, I recall CopyGuard now. Wow. Takes me back.
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  #32  
06-08-2017, 09:29 AM
sanlyn sanlyn is offline
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The problem of 20 pixels of grayed area along the bottom of the captures with the PA-100 was solved by JVRaines, here:
http://www.digitalfaq.com/forum/vide...html#post44422

The trimmer adjustment was extremely small, and cleared the problem.
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  #33  
06-08-2017, 01:05 PM
robjv1 robjv1 is offline
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Worked great for me too. The adjustment was a very, very light turn with the screwdriver. Took me a little bit of trial and error to hit the sweet spot.

In my case, there was a slight gap between the bottom of the underscan area and the color corrected area, so masking it was losing a little more than I wanted to.
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