Why is picture clear on TV, but not capture card?
 

hey guys,

one of experiment, I plug RCA out put to my laptop with USB ADC, and the picture was awful and there is scraches and noisy picture even there is no VHS , just welcoming page of VCR
while in the same time I plug it to old TV and the picture was like a glass ,,, sooooo clean.
Why ? what is going behind the scene .
By the way , with same ADC with same laptop with same color system of tape with different VCR had such a good result.

So I just change VCR ,,,, why this VCR work with only TV and not work with ADC

see attachment

The title of this should be something Why is picture clear on tv but not card. Something more specific so people having the same issue can find this thread later. Also adding tags is a good idea.

https://www.digitalfaq.com/forum/vid...-vhs-tape.html

you have a great title but I could not edit any more . I am bad in expression and in Tags, unfortunately

It’s okay. I wouldn’t worry about it. I do that same thing sometimes I was just letting you know. I also bring up stuff that is way off topic in threads and kind of derail the thread sometimes. I’m trying not to do that as bad. The people that have been members for a long time don’t really do that soo bad. All that just helps with the organization of the site and it helps people that are trying to learn by looking up old threads.

I hope that thread answered your question.

Title fixed.

Fun fact, even I don't use tags.
That SEO went out years ago: https://www.youtube.com/watch?v=OUh0MVFJ1EY
When the forum gets upgrade, all of that should vanish. I think.

Back to topic, you have noise patterning from somewhere. Too many variables. So from VCR, wires, the menu itself (non-standard generated video), the capture card.

to isolate this issue,
I keep all setup as same and just change the VCR. the result become so good.
but in general, even when I use good VCR it is not 100% like TV. the picture in TV is like a glass. it is clear in very good way.
is that possible to capture like this clear signal ?

Any solution to have great and clear signal capture card like TV exactly?

Get a better capture device.

I have Blackmagic intensity Pro , also tried Elgato , Tried C725b card , tried Aja analog/digital convertor ..
any suggestion better than these

I use same setup but instead of capture card I replace it with TV. It means that capture card is not good.
By the way I use same capture card with Camcorder 8mm D8 and the picture is so clean and good.
there is no chroma nosie like in the picture. this issue is only appeared when I use VHS capture. If I plugged it into TV directly the picture would be fantastic

Lordsmurf has his hand in a cast and isn’t really typing as much for the moment. These kind of questions pretty well any member can answer. I think it is answered though in the link I sent.

In what way you think the TV looks better? Are you comparing the small window on the capture application, or the captured file, either way you're still comparing apples to oranges, TV de-interlaces the video, the capture card doesn't, Need more than just a blue screen to come up with such a claim.

Analog signal is a wave. A digital signal is steps. A capture card take in the analog wave and samples it applying 8 bits (2 to the power of 8) of information at every sample point. Those samples are the steps. Timebase errors make it hard for the card to sample the signal. A TV doesn’t work the same way. It doesn’t have to do the same thing.

Ah, thanks again for answering my questions. But some time my questions considered as basics or logic . thats why I am trying to under stand what is going on in digitizations.

and for actually am not comparing small window VS TV . but I am comparing the result of capturing VS TV . I did not know that TV also has to be processed the signal before show it in screen.

about the link u provide it in this thread. This what I am looking for . it is exactly talking about my issues.

A lot of people’s questions are basic when they first start. YouTube is sometimes wrong and definitely isn’t a good place to find digitizing techniques but if you are having trouble with a particular concept some YouTube videos will slowly walk you through it with visual representations that can be helpful. If you are wondering what is going on in digitizing you have to figure out the difference between a digital and an analog signal first. https://youtu.be/j7-acuTio4M?si=zN-IqXMV5PRuv7fU.
https://www.digitalfaq.com/guides/vi...nd-sources.htm

Let me illustrate this conversation with an analogy:

When I step on the car gas pedal, it makes noise.
When I step on my cat's tail, it makes noise. The "MEOW!" sounds better to my ears.
Why?

Both are white ------- just like both USB ADC and TV are "video".

Are you seeing the problem here?
One is not like the other, even if you're wrongly thinking it is.

I know, it can be hard to understand when new. What you think you know, you don't know. In fact, you don't (yet) know what you don't know. That's part of learning. We shall help you fix that.

When trying to comprehend video capture, the TV is not helpful whatsoever. It may as well be an empty box. There is literally zero comparisons to be had here. A viewing device is wholly different than signal, playback, or ingest devices.

At least a TV proves there's something on the tape. I agree that if it looks good on the TV, it may not be that good after digitisation, but if it looks bad on the TV, then at least you know the recording itself is probably bad and it is not your capture process.

That "What is Analog and digital" YT provides no relevant information for digitising videos. It's not that hard; plug your VCR into a digitiser (via a TBC if you like) and start the capture. The theory is irrelevant. All that jargon isn't going to get you a better result. What counts is a good VCR and a good digitiser. Just don't go re-copying and re-copying tapes ad-infinitum.

@ahmed12h, if I'm reading your first post correctly, the second VCR is good, so it must be a defect with the 1st VCR. Maybe low output signal strength (if that's possible), enough for the TV but not enough for the digitisers?

Did you ever get an actual video image on the TV or digitiser from VCR 1? Those two images in post 1 are blue screens. I don't think they'd be a valid method of comparing the two scenarios.

He said he wanted to learn about digitization. You need to learn the differences in the signal for that. You have a good point though.

Yes, it does make for a good troubleshoot, for a basic process of elimination, for certain unknowns. In this exact use case, it eliminates the entire capture workflow, just preview tape contents from VCR. (Of course, VCR is still variable, until checked.)