ArcadeVGA resolutions are bad calibrated or what ?

[tisurame]

I compared this problem with two resolutions: 320x240 and 640x480 (both have the same aspect ratio, so the result is the same).

I used Visualboy Advance, playing Castlevania Aria of Sorrow, because (without stretch) you have a small and centered screen, with top and botton borders. Then, its easier to notice any change on the picture size. And also because a moon appears on the title screen (good to know if the aspect ratio is wrong or not).

As a video output, I used ArcadeVGA itself, Svideo output from ArcadeVGA and a Matrox Card running at 15khz through AdvanceCab (320x240 and 640x480).

The aspect ratio of the Svideo output and Matrox card was the same, but the ArcadeVGA picture was different from both. With Svideo and Matrox you can clearly see that the picture is much wider (which is correct, since we are talking about a GBA game) than the picture using ArcadeVGA (that looked like a square).

The moon from the game title screen, with the svideo and Matrox, is a perfect circle. But with ArcadeVGA it looks vertically stretched (or horizontally compressed)

I thought that playing GBA games with a 4:3 resolution really looked like this. And I always wondered why people didnt notice the wrong aspect ratio. But now I know the problem is with ArcadeVGA. Playing GBA with a PC Monitor and regular video card looks correct.

Is there any solution for this ? ArcadeVGA video modes are bad calibrated ?

[wpcmame]

You control the the width of the visible area with the H-Size knob on the monitor. You need to calibrate it for the card you use.

The ArcadeVGA probably use a slightly higher pixel clock than the matrox card for the same resolution (which means a slightly narrower image). You can't say that one card is better clibrated unless you get different aspect ratio at 640x480 than 320x240 on the same card.

Best way to adjust the monitor is to run a vector game (e.g. asteroids) in mame. The reason is the startup screen which will have a white border with the same size as the resolution you specify.

e.g.
mame asteroid -r 320x240
mame asteroid -r 640x480

(you might need to add -noka if you specify a non 4:3 resolution)

[tisurame]

Well, the problem is if I adjust the horizontal size for 320x240 on the monitor , it will mess with other resolutions.

[Minwah]

Well, the problem is if I adjust the horizontal size for 320x240 on the monitor , it will mess with other resolutions.

Arcade monitors are designed to be run at one resolution (they normally have one game in them at a time).  So some slight difference in size between modes is normal.

I use many resolutions tho and the difference in horizontal size is minimal enough to not worry about or notice.  Vertical size is more of a issue, so some comprimise has to be made (I fit ~256 lines onscreen).

[wpcmame]

Arcade monitors are designed to be run at one resolution (they normally have one game in them at a time).

[RayB]

Well, the problem is if I adjust the horizontal size for 320x240 on the monitor , it will mess with other resolutions.

You have to settle for having black borders in some games. Or force MAME to use one resolution and stretch the image to fill it in.