Don't understand how to adjust my display over HDMI

[Cyber Akuma]

I was never good at figuring out adjusting display settings, especially back when I had to manually adjust my CRT monitors. For now I am using my MiSTer on HDMI but still not really sure how to do it properly. I want to replicate the original aspect of the image as correctly as possible.

Thankfully there are both official and unofficial versions of the 240p suite for most major systems to help, but feels like I am not getting something. Using the horizontal bars I realized that the default scaling was distorting the image, and by setting the video scale from "Normal" to "V-Integer" fixes it, even if it shrinks the image a little, but the vertical stripes are not correct. Setting it to "Wider H-V Integer" fixes that, and makes the checkerboard completely uniform, but then for just about every core the image is very clearly stretched when I do this but appears correct in the 240p suite.

I am very confused by this, why are the lines and checkerboard correct with wide H-V Integer but clearly stretched when in-game?

Does this have something to do with different resolutions some of the consoles could switch between? Or how some of them apparently didn't have square pixels and intended for the CRT to alter them correctly? How do I even account for that? I tried lookin up if there are any guides for doing this for each console but could not find any.

And does the resolution of the TV also effect this? The main TV I will be connecting it to is 4K, but I am also going to be connecting it to many 1080p screens occasionally. And currently I have it connected to a 720p screen for now. Does even this effect the image looking more stretched or squished the aspect ratio between scale set to Normal, V-Integer, and Wide H-V Integer if I move it across HDMI TVs of different resolutions?

The PSX seemed to be the hardest to do, setting it to Wide H-V heavily squished the two boot screens. I know the PSX was well known for many games switching between 240 and 480, I think SNES too, so not sure what to even do about this, there doesn't seen to be a way to change the scaling based on the output resolution.

Though the part that confuses me the most is why the default is "Normal" when that one seems to universally be incorrect over every core (Or is that just because I am currently using a 720p screen?)

Any help or advice on all of this? I am not sure where to even begin.

[rhester72]

It has to do with non-square pixels. Virtually all 4:3 systems back in the day managed to do so by "squashing" pixel widths appropriately, and the result is that you have to make a decision between mapping to 1:1 pixel displays (meaning the famous 'checkerboard' is presented with high visual acuity but obviously wrong aspect, or instead maintaining correct aspect ratio at the expense of dropping vertical pixel lines). You can't achieve both simultaneously without using a CRT, unfortunately.

[Cyber Akuma]

So my aspect will always be off regardless of what I do when using HDMI on a modern display? Do I at least have an option to prevent squishing or stretching the image? I tried comparing it to software emulators too but I still could not figure out what was the correct aspect.

E.G. Spyro on the PS1, with V-Integer the boot screen showing the Earth looks squished a bit, but it looked that way on software emulation too, with Wide H-V it looks like a circle, but other things look stretched then. I can't tell what is correct.

[rhester72]

If you use "Normal" (versus anything-integer), that will be the correct aspect ratio.

[Cyber Akuma]

Normal? You sure? That appeared to be the only one that was conclusively the wrong aspect.

[rhester72]

Yes indeed.

If you set to Normal and literally measure the width against the height, does it equal 1.33? (Pick a specific core and title to test with so there's at least a known quantity.)