You are certainly remembering this wrong, all VGA video cards output double scanned low resolution modes to reach 31KHz that all VGA monitors require. It is possible to reprogram the CRTC to do only single scan but you will need a special monitor than can sync to 15KHz and they are not common and are quite sought after.

Only an EGA or CGA card with appropriate monitor will show the lines once since they are 15KHz natively and the monitors are too.

Tiido wrote on 2021-12-14, 09:53:

You are certainly remembering this wrong, all VGA video cards output double scanned low resolution modes to reach 31KHz that all VGA monitors require. It is possible to reprogram the CRTC to do only single scan but you will need a special monitor than can sync to 15KHz and they are not common and are quite sought after.

Only an EGA or CGA card with appropriate monitor will show the lines once since they are 15KHz natively and the monitors are too.

Very strange, I played daggerfal and doom for years. The way remember these pixels were single scan. No way with the doom face like souble scanlines, look at that.
Also I remember that my friend's P120 was showing the graphics with doublelines. I'm surely remember that my monitor was very dark, since I played the daggerfall with light spell every time, and played the quake with gamma cranked up. it was an old (even in 1994) 14"monitor.

The low-res vga modes were always using scan doubling.
The required timings of the VGA display pretty much mandates scan doubling to allow "real" 200 lines to be shown.
Related video: https://www.youtube.com/watch?v=hQBoAyRo624

What you call "a proper look" could only be seen on a CGA monitor with its lower scanning frequencies, or on a TV if your card had TV output.

Maybe you had a better monitor than you do now, with good enough focus that scanlines were distinct even with the double scan :

Tiido wrote on 2021-12-14, 11:09:

Maybe you had a better monitor than you do now, with good enough focus that scanlines were distinct even with the double scan :
IMG_7848.jpg

Yeah, this is how everything looked on my Philips 170P Brilliance monitor. Before that I had a shitty Hyundai 17" CRT and to be honest it was a blurry mess with all kinds of abberration/ghosting that made it impossible to see pixels/scanlines.

Could it be that you had a Trinitron monitor back in the day?

They do look slightly different compared to Shadow Mask monitors, but certainly not to the extent that you're describing.

@vstrakh
I see what your point is. But I'm also pretty sure about what I had on my monitor back in 1995. The games I was playing were VGA games with 256 colors.

@Tildo
Yes, I can also see the scanlines with the doublescan on this monitor too. but since there is 2 for every line, it looks like we're seeing them through an LCD screen. Check the ears of the face on the doom. those 90 degrees ruins the feel.

@Jeseph_Joestar
I don't think it was a trinitron because glass curvature of it was not only from left to right. It also had curvature from top to bottom as well.

To decribe what I mean "proper" in a better way, you can see the dithering and color transition on POP 2. Deep scanlines were letting us filling the gaps within our brain to see the better gradient color transitions (check the sky color).

It also works for the diagonal pixellated designs. You can see the arm of the prince.

Non double-scanned 200p from a DOS machine looks awesome on my arcade monitor, regardless

The VGATV TSR is your friend
http://mirrors.arcadecontrols.com/VGATV/pwp.n … bo.pt/pscoelho/

maxtherabbit wrote on 2021-12-14, 23:20:

Non double-scanned 200p from a DOS machine looks awesome on my arcade monitor, regardless

The VGATV TSR is your friend
http://mirrors.arcadecontrols.com/VGATV/pwp.n … bo.pt/pscoelho/

Thanks for this precious advice. Once I relocate my Commodore 1084 monitor to my home, I will give it a try. It converts the VGA output into RGB for these monitors, lucky I have a 1084 😀

Also this quotation from the FAQ section "probably" confirms that old VGA monitors has a potential to show 200 lines without doubling it. Which means I was not dreaming 😜

3 - Do I need to do that hardware thing?
Not really. You have 2 (well 3) options:

- You can use a regular 15Khz monitor (those from Amigas, Ataris, probably old VGA monitors as well) that takes a VGA input;

Don't get carried away. Yes 15kHz/31kHz dual scan VGA monitors did exist back in the day but they were far, far from common

Well there were cheap ones before the MPR II babies ruined things, just overdriven 15khz models basically, huge dot pitch still .... yet having the advantage that after a few weeks of 10 hour a day use at close range you could read a book at night by the glow off your face 😉 .. though that was always causing arguments about whether it was the higher energy X-rays causing nuclear decay of certain atoms in the skin, or just atoms of phosphor getting blown out, quantum tunnelled through the glass, and getting tattooed into you. 😉

Even if one had a multiscan monitor capable of showing 15KHz, you still needed a TSR or some other form of help to actually turn the low res modes of the video card to 15KHz single scan ones, no stock video BIOS outputs those modes.

The only way I could remember getting a low, non-doublescanned video mode on a 'tron VGA CRT in the 90s was some 256x256x8 ModeX mode, and there it appeared squished.

the only monitor I remember showing such image was my Commodore 1084S.

If you have a large CRT, it's possible to have distinct scanlines in some of the standard VGA modes. On my 17" monitor the "EGA hi-res" mode (640x350) has quite distinct scanlines. The 350 line VGA mode is actually the exact same video timings as the double scanned 400 line modes (e.g. the 320x200 mode used by most 256 colour VGA games) but with different sync polarity -- this causes the monitor to stretch the image vertically so that the "extra" 50 lines disappear off the top/bottom of the screen.