Video capture Atari 800 to Windows 10 laptop

[Fred Toronto]

Hello folks... just recently resurrected my Atari 800 and was looking to display video output from it in a window on my Windows laptop.

 

To that end, I've invested in an S-Video cable from 8-bit Classics. This works fine if I connect to a monitor. I plug the large 5-pin end into the 5-pin S-Video port on the 800, and on the other end the red/white/yellow composite plugs into the monitor. Displays a nice clean image.

 

Now, I'd like to take that video and display it in a window on my Windows laptop instead. I've got a video capture device from UCEC, which has composite and S-video connectors on one end, and a USB connector on the other. So the chain is as follows:

 

Atari 800 --> S-video cable --> S-video connector on UCEC vidcap device --> USB to USB-C cable --> USB-C port on my laptop.

 

Then I run OBS software, and I'm able to view the video in a window. The problem is that the default blue background we're all familiar with is instead a very pale blue, almost white, making the "READY" prompt and any text almost unreadable. See image.

 

I've played around with every video-related setting I can find in OBS, to no avail.

 

Any ideas?

 

Thanks!

 

 

[Rybags]

Can't say I've had the same problem.  I've had reasonable picture from every device I've used which would include several PCI cards and a recently bought USB capture device with the usual composite and S-Video inputs.

 

See if VirtualDub from phaeron's site http://virtualdub.org works better.

It should give you access to all the available driver dialogs.  Often there's stuff like brightness and contrast overrides which might help.

[+DrVenkman]

Some inexpensive cables don’t properly separate the Luma and Chroma on their S-video connections. In fact, sometimes they have the Chroma pin carrying a complained Composite signal (Chroma + Luma) rather than only Chroma. This can cause lots of issues with capture devices that don’t have comb filters. If you can, try connecting just Composite video into the capture device and see if your picture improves. If you con’t have a Composite cable for your computer, you can buy or make an inexpensive adapter that connects to an S-video output and provides 2 separate RCA plugs - one for Luma, the other for Chroma.

[jacobus]

Sorry, OT -

9 hours ago, Fred Toronto said:

Hello folks... just recently resurrected my Atari 800 and was looking to display video output from it in a window on my Windows laptop.

 

Sorry OT, but you wouldn't be the Fred who is famous for his elevator repair skills, would you?

[Fred Toronto]

Haha yes that’s me ?. Just fired up my old 800 for the first time in about 25 years!

[Fred Toronto]

Thanks @DrVenkman. Can anyone recommend a video capture device that does handle S video correctly?

[+DrVenkman]

12 minutes ago, Fred Toronto said:

Thanks @DrVenkman. Can anyone recommend a video capture device that does handle S video correctly?

To be clear, it may not be the capture device - it might well be the cable. Some cable manufacturers put the combined Composite signal out through the Chroma line, expecting a comb filter in a consumer TV to eliminate the “extra” Luma signal from the Chroma pin. I’ve run into this even in “high end” Monster-brand S-video cables from the 90’s. Not sure that’s what’s going on with your Atari 800 video cable, but stranger things have happened. 

[Fred Toronto]

The cable I'm using is from 8-bit Classics (https://www.8bitclassics.com/) who seem to specialize in Atari 8 bit and C64, so I would assume they wouldn't have taken such a shortcut, but I don't know.

 

I've emailed them to see if they have any insights.

 

Thanks again!

[_The Doctor__]

assume nothing!

[Fred Toronto]

Process of elimination... I was able to hook the S-video output of the cable to a TV with an S-Video input, and the image is clean. Must be the video capture device (or the software)!

[jacobus]

21 hours ago, Fred Toronto said:

Haha yes that’s me ?. Just fired up my old 800 for the first time in about 25 years!

Welcome back Fred!  In case you hadn't guessed it, I'm Jim from the HBO ?

[ivop]

It looks like the "capture gain" is way too high and everything is washed out. Either the signal is too hot, or it's a problem with the device. Hopefully you can turn the gain down, either in software or with a hardware setting.

 

This reminds me of connecting an N64 to a modern television through composite video. You need to add a 75Ω resistor in series in the cable to not have it look all whitish without much contrast.

[Fred Toronto]

2 hours ago, jacobus said:

Welcome back Fred!  In case you hadn't guessed it, I'm Jim from the HBO ?

Haha! Once an Atarian, always an Atarian I guess.

 

HBO User Group - that was a lifetime ago!

[Fred Toronto]

1 hour ago, ivop said:

It looks like the "capture gain" is way too high and everything is washed out. Either the signal is too hot, or it's a problem with the device. Hopefully you can turn the gain down, either in software or with a hardware setting.

 

This reminds me of connecting an N64 to a modern television through composite video. You need to add a 75Ω resistor in series in the cable to not have it look all whitish without much contrast.

Thanks Ivop.

 

So I tried the composite input on the video capture device instead of S-Video. Now the image looks more or less normal (white text on blue background in Notepad e.g.), albeit not as clean as the S-Video. Unfortunately, the colour palette is still off somewhat... a video game that is supposed to have a blue background is closer to purple. Will have to see if I can tweak the palette to correct for that.

[+DrVenkman]

41 minutes ago, Fred Toronto said:

Will have to see if I can tweak the palette to correct for that.

The color potentiometer in your 800 has probably gotten a little out of range due to age-related changes to resistance. I can’t recall if the color pot on the 800 is accessible through the case without disassembly (my 800’s are in another room right now), but in any case, if you let the machine warm up for 10 minutes or so you can then adjust the color output to calibrate it better to your display and capture device(s).

[+mytek]

2 hours ago, ivop said:

This reminds me of connecting an N64 to a modern television through composite video. You need to add a 75Ω resistor in series in the cable to not have it look all whitish without much contrast.

Also another possibility along the same lines is that there is no 75 ohm termination on the capture device, so adding 75 ohm resistors from luma and chroma to ground might also be something to try. Best to do this at a point close to the input of the capture device.

[Fred Toronto]

6 hours ago, mytek said:

Also another possibility along the same lines is that there is no 75 ohm termination on the capture device, so adding 75 ohm resistors from luma and chroma to ground might also be something to try. Best to do this at a point close to the input of the capture device.

Thanks mytek - but that sounds way beyond my capabilities LOL.

[Fred Toronto]

6 hours ago, DrVenkman said:

The color potentiometer in your 800 has probably gotten a little out of range due to age-related changes to resistance. I can’t recall if the color pot on the 800 is accessible through the case without disassembly (my 800’s are in another room right now), but in any case, if you let the machine warm up for 10 minutes or so you can then adjust the color output to calibrate it better to your display and capture device(s).

Thanks DrVenkman, but the image is perfect when I hook up my Atari to an older flat-screen Sharp TV via S-video. So the fault must lie somewhere within the video capture device.