Dimness issues with S-VHS VCRs?

[crissrudd4554]

I'm writing in regards to something that I've been trying to override for almost two years now. I've been doing captures with S-VHS VCR's for the last couple years. I presently have two. Panasonic AG-1980 and JVC HR-S9900u. They both work nice but I lean more towards the JVC. But there's one consistent thing that aggravates me with both machines. The TBC will cause occasional issues where the image might go a tad dim in spots and maybe a tad bright in others. Case and point. Watch how this shot goes a tad dark towards the end.

https://gifmaker.me/video-to-gif/vie...fk-v5rGvz-hnet

https://i.postimg.cc/nc2My041/GIFMaker-me.gif

What do I do about this?? I've tried two external TBC's in the past few months (one I even purchased from a member of this site) and they did not fix the problem. I had other problems with the TBC's as well. One actually caused a DVD recorder I was using to shut down after 15 minutes of recording. Regardless I bought them to hopefully alleviate this problem. They did not. Do I need to try another VCR?? Because right now I'm at a compromise. Use regular non-S-VHS VCR's with a DVD recorder as a pass through and just ignore the minor frame jumps I'll get with those recordings or stick with the S-VHS players and live with the dimness issues. Really don't want either scenario. Suggestions???

[lordsmurf]

You're running into AGC issues. That may mean capture card, or an interaction. Which card?

[crissrudd4554]

It’s not a capture card issue because it occurs with more or less ALL my capturing methods. This includes DVD recorders as well as capture cards.

-- merged --

I mean if everyone wants a brief round down of my capturing methods then fine. I’m just gonna list what I frequently use.

DVD Recorders:

JVC DR-M10
Panasonic ES15
Sony VRD-MC6

Capture cards:

WinTV HR-850/950
Magica Capit
VIDBOX NW03/NWO7

But as I mentioned regardless of which method I try the issue seems to to surface regardless of my configuration. DVD recorder to VCR, capture card to VCR, external TBC, no external TBC, S-VIDEO, composite, the fluctuation appears in some form or other. Some instances are better than others but it’s never gone. Leaning more towards VCR issue because it happens with both my S-VHS players. Little to never with regular consumer VCR’s. Any suggestions??

[lordsmurf]

JVC M10 can have AGC effects, but rarely stark.

Panasonic ES15 has AGC that you notice the moment it gets turned on.

850 or 950? Both can be ATI 600 USB clones, but most are not. The "not" have AGC aggression for certain. The ATI 600 USB can have AGC effects, but lessened.

Everything has AGC. The artifacts strike most at extreme darks and lights, and is very noticeable when dark.

Anti-copy screws with the signal even more, even when "ignored" or "defeated". It's more like "diminished to near-nothing" than outright "removed".

VCRs, TBCs, DVD recorders, capture cards -- all have AGC. That's just the nature of consumer analog formats. It has to be.

Your projects are niche edge cases, it seems, so you're getting into the weeds of video, lots of scenarios where you can easily see the AGC.

The goal is to have AGC changes remain minor, or at least not be obvious.

Luma gain can drift downwards or upwards over time, or between sources, the AGC keeps it in check, somewhat like bumper bowling for kids. Without AGC, without bumpers, you have gutter balls.

[aramkolt]

Could that be macrovision? Looks like a scene from Star Wars you've got there perhaps.

I had no idea that blu ray and analog outputting streaming devices still use macrovision, but apparently they do:
https://www.youtube.com/watch?v=vtr9tr97KQ4

Would be curious if your issue goes away if you use it with either a good full frame TBC or the Sima Copymaster. Seems like the Sima Copy master simply strips out the normally off-screen areas such as closed captioning and regenerates the horizontal sync pulses where macrovision normally resides to mess with the automatic gain control which gives you the fluctuations in bright and dark.

The Sima has S-Video and Composite in and out.

[crissrudd4554]

It occurs with non-copy protected tapes as well as copy protected tapes so I honestly couldn’t tell ya.

So I’m a nutshell there’s much way to adjust this???

-- merged --

Well even if it doesn’t improve the issue I got myself that SIMA device since I need a new stabilizer device anyways since my go to one doesn’t seem to want to work with my JVC DVD recorder. I have another device that seems to work with it but it has a black vertical line in the center.

-- merged --

Well unfortunately the SIMA doesn’t seem to override copy protection when used with the JVC DR-M10 DVD recorder.

EDIT: Scratch that. Tried a different setup. Works now.

But now I have a different question. Why does this thing shift the image further to the left????

-- merged --

I'm presently testing a recording and while I won't say the SIMA "fixes" the problem from what I'm seeing it does actually make it somewhat less noticeable. It even improves the colors to some degree. There's a few other drawbacks though. In some places it causes minor tearing on the top edge but honestly its in the overscan area anyway so I could let it slide. The one MAJOR drawback though is the image being shifted to the left which also clips a small portion of the left edge off.

Without SIMA Copymaster

vlcsnap-2023-08-28-17h48m27s811.png

With SIMA Copymaster

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Is this a byproduct of this device?? Is it faulty?? Is there other SIMA devices I should test. And yes every tape I've tested with it does this.

[aramkolt]

Hmm. I'll have to see if I can find mine and see if it does the left shift thing. I have always noticed that the far left seems to have a couple pixels of odd coloration and you can kind of see it there in your sample clips. It's possible it's purposely cutting those to give a cleaner overall image and yeah, I suppose the black bar on the right would also be in the overscan area typically. Wonder if your capture is set to 704x480 if that would matter?

You could probably pop the cover off the sima and see if there are any potentiometers inside which could be the horizontal position maybe?

Also would be interesting to see a short video clip with and without the sima.

Agree that the image looks noticeably better color-wise with the sima, almost as though contrast has been increased, or possibly "less soft" though without actual sharpening artifacts that I'm able to see.

[crissrudd4554]

I’ll try to get clips posted tomorrow. I’ll also trying opening the device and posting pics too.

-- merged --

I’ll have clips tomorrow. Sorry for delays. I was waiting for additional hardware and doing more tests but anyways this is the inside of the unit. Anything specific I should be looking at???

737839E9-E66F-4879-B9AE-7962799AA4B0.jpg

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I'll have more clips tomorrow. Did some tests with AND without the SIMA with my Capit card and what do you know?? No shifting. Yet when I try the device with my JVC DVD recorder or my Sony DVD recorder the image shifts. I'll try to have those clips tomorrow. For now my Capit clips.

W/O SIMA

982946EB-2009-439D-93FA-1FB517B18A80.jpg

With SIMA

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Quote:

Originally Posted by lordsmurf

Your projects are niche edge cases, it seems, so you're getting into the weeds of video, lots of scenarios where you can easily see the AGC.

The goal is to have AGC changes remain minor, or at least not be obvious.

How would you suggest I do this?? I keep testing the same tapes and each time is on either my JVC or Panasonic S-VHS players these AGC issues are very visible. How do I reduce it??

[latreche34]

Looking at your samples I don't see the AGC being an issue, I think all VCRs exhibit that trying to keep the levels within a certain tolerance, You are looking for a modern digital video perfection that unfortunately did not exist in 19 century technology.
Just so you know that Copymaster box is not a TBC, it does not store video in a digital memory, it just ignores the copy protection signal in the VBI.

[lordsmurf]

Quote:

Originally Posted by crissrudd4554

How would you suggest I do this??

Sima was the low-end consumer products division of Cypress, and quality was often compromised, or the device was over-advertised with weak or non-existent abilities. Some of the "higher-end" (oxymoron?) Sima were known to remove anti-copy, but mostly the SCC2. But also noting that removing anti-copy sometimes has the added "bonus" of also harming the image quality in various ways (hot luma, etc).

I don't readily see what you're trying to show in those attached MPEG samples. Spell it out.

I agree with latreche34 here. Pixel perfection does not exist on analog. That's not an excuse to create crappy conversions. But at some point, there are diminishing returns.

Quote:

Originally Posted by latreche34

VCRs ... trying to keep the levels within a certain tolerance,

That's just AGC ... right?

[latreche34]

Yes, that's what the AGC does, compensate for levels and try to keep them within a certain legal tolerance, Some of those tiny level variations can even happen during recording the tape, This is why they had high end recording/editing machines with TBC back in the day, to produce high quality stable recordings, If the recording is made by mom and dad's basement VCR don't expect miracles.

Having said that, we don't see a problem, maybe you can point it out to us better.

[crissrudd4554]

The clips and screenshots was more to show how the SIMA was making the image shift to the left depending on the setup, not so much to illustrate the AGC issues (if that even is the problem here) but I will post more clips to illustrate the problem.

Spit it out??? Okay again like I said in my initial post when I make recordings be it with a capture card to my computer or from the VCR to a DVD recorder, with either of my two S-VHS players I frequently get the spots where it either goes slightly dark or slightly bright. This is a RARE occurrence if I use a regular NON-S-VHS VCR. For instance when I capture with say my Panasonic PV-V4523S VCR I don’t have these issues. But if I use a normal VCR with a DVD recorder as a TBC like pass through I get occasional frame jumps. If necessary I’ll post examples of this too.

Also just for clarification I KNOW the SIMA is not a TBC. I was not trying to use it as one. The issue I’m having happens with none copy protected tapes as well.

[lordsmurf]

I don't always reply to just the person asking the question, but address future would-be readers. That extra info can make a big difference at times. Certain bits of info cannot be stressed enough.

Alright, got it, image offset. That happens on lots of gear. Understand that the image does not exist as "centered" really. This gets into analog signal theory. The signal is taller and wider when demodulated into the image. It can vary tape to tape, deck to deck. It's not the device that causes it, but rather device interactions that cause it. Some of that wibbly-wobbly stuff that few people worry about, even those us of that know how/why. Again, analog is not pixel perfect saved data. There is room for interpretation by the playback and signal passthrough devices in a workflow.

AGC issues can sometimes be created when devices compete for ownership. So the VCR moves levels, the DVD recorder compensates. That why devices known to correct less, mostly certain capture cards, do better here, no competing, no trying to own the signal.

[crissrudd4554]

Alright I have a couple more gifs. Note how in both it gets a tad brighter midway?? Yes I know they're small and dark and you may wanna watch these in a dimly lit room but its there.

https://i.imgflip.com/7y95jx.gif

https://i.imgflip.com/7y95ox.gif

But its vice versa. Sometimes it'll go a tad lighter sometimes it'll go a tad darker. But one thing that is for sure is its a frequent occurrence when using my S-VHS players regardless of my capturing method. However, if I take the option of using a regular VCR with a DVD recorder as a passthrough I run into this issue.

https://i.imgflip.com/7y95s8.gif

Note how there's a subtle jump when he leans towards her?? These are those subtle jumps I've mentioned if I use a non-S-VHS VCR with either my JVC or Panasonic DVD recorder. For comparison here's the clip minus a jump.

https://i.imgflip.com/7y95uh.gif

-- merged --

Heads up. Links to those GIFs might not work on mobile.

[lordsmurf]

Dropped frames.

[crissrudd4554]

Exactly but it’s another one of those happens regardless of the recording method, one of the advantages of the S-VHS’ units built in TBC.

[latreche34]

Now it is not a level issue, it's a jumping issue? I think you are just knitting and picking, VHS is not perfect, that is I'm sure of.
The first two links did not work for me on a computer.

[lordsmurf]

I'd not call it picky. Some of those are bad errors. Others are just byproducts of the gear/tech in use. I don't have issue trying to resolve those, and in fact encourage it. But at some point, you do run into diminishing returns. Just learn where those are. Don't stop to early, and also don't try to keep push the immovable.

[crissrudd4554]

Sorry I’ve been MIA but I was doing further tests and well now I have a weird problem. Now my JVC VCR is shifting the image to the left even WITHOUT the SIMA or any other devices in the chain. I even did a test on my computer just VCR>CARD>Computer and yeah shifted image. I mean it’s not BAD but does strike me as odd that this never happened before. Is this an alignment issue??? Playback is still fine but yeah slightly shifted. I’ll post pics tomorrow.

I'm gonna start a new thread for this new problem I have.

-- merged --

Well after doing some additional tests I found my alternative although it’s a somewhat more expensive one. I upgraded to the JVC HR-S9911U and while it does have some occasional minor dimness issues, when combined with my Panasonic ES15 DVD recorder as a TBC standin they look far FAR less worse than the S9900u or the Panasonic AG1980 and are also far FAR less frequent. So as of right now this is the route I’m going on.