PS2 Seemingly incorrect NTSC scaling with PAL PS2 on CRT

[vonpedal]

Hi!

I recently installed FHDB 1.93 on an SSD (the newest version didn't advance beyond the FMCB logo so I went with this) and both NTSC and PAL games are loading fine on my 30004 model PAL PS2 through OPLGSM 0.9.2. However, there is something off about the image being sent to my CRT. It is not super noticeable, but there is definitely something wrong about how the image is being scaled it seems. It's as if the image isn't aligning properly to the slot mask of the CRT. Or as if the image and each line is being drawn ever so off from where they should be, resulting in an image that is more jagged and more flickery than interlaced 480 should be. However, I've run the PAL version of Rayman 3 in its 60Hz/NTSC mode and that results in a clean and solid image looking how it is supposed to, so with that in mind there shouldn't be any problem with this particular PAL PS2-CRT combo running 60Hz/NTSC content, unless I am missing something.

I split the SCART RGB signal and sent the other one to an OSSC to examine the actual resolution and fps and both Rayman 3 in the 60Hz mode and the NTSC ISOs running through OPL read 525i, 15.73kHz, 59.94Hz so I am stumped as to why NTSC games render incorrectly through OPL vs NTSC content from disc.

I've attached images showing the phenomenon. In it you can see how the CRT looks when given a proper image vs how it behaves when being fed an incorrect one. The problem manifests itself most noticeably in these images as sort of wavy patches of the image towards the edges of the screen where parts of the image almost seem to fall between the rows of the slot mask. Any ideas?

(The attached image is somewhat large. It kind of has to be for me to adequately resolve the fine CRT details, so make sure to view it at 1:1)

 

[arcadekidflo]

1. Try to disable the modchip , you you have any
2. Try to force NTSC in the game's settings in OPL
3. OPL 0.9.2 ? Why not newer ?

 

[vonpedal]

Thanks for the reply

No modchip installed. And I also just tried with version 1.1.0 of OPL. (0.9.2 was the one that came with the FHDB install). These are the steps I've already tested:

- Tried forcing different modes through OPL. NTSC, PAL and PAL60. They all exhibit the same problems.
- Tried setting the system mode to either PAL or NTSC before booting into OPL.
- Tested Rayman 3's 60Hz mode to exclude NTSC/60Hz being the problem with this specific PAL PS2-CRT setup. No problem here and 60Hz works and looks great. No jaggies, no excessive flickering.
- Split the SCART signal from the PS2 and sent the other one to an OSSC to examine the actual resolutions and frame rate. Rayman 3's 60Hz mode reads as 525i, 15.73kHz at 59.94Hz, the same as what the NTSC ISOs on the HDD read.

Also, here's a smaller, cropped version illustrating the issue:

 

[arcadekidflo]

It looks like some kind of " nearest neighbour " filter but the result is worse than the original .

To be able to figure out the cause you need to try :

1. another TV or even capture card
or
2. another set of video cables
or
3. another console

 

[Peppe90]

Thanks for the reply

No modchip installed. And I also just tried with version 1.1.0 of OPL. (0.9.2 was the one that came with the FHDB install). These are the steps I've already tested:

- Tried forcing different modes through OPL. NTSC, PAL and PAL60. They all exhibit the same problems.
- Tried setting the system mode to either PAL or NTSC before booting into OPL.
- Tested Rayman 3's 60Hz mode to exclude NTSC/60Hz being the problem with this specific PAL PS2-CRT setup. No problem here and 60Hz works and looks great. No jaggies, no excessive flickering.
- Split the SCART signal from the PS2 and sent the other one to an OSSC to examine the actual resolutions and frame rate. Rayman 3's 60Hz mode reads as 525i, 15.73kHz at 59.94Hz, the same as what the NTSC ISOs on the HDD read.

Also, here's a smaller, cropped version illustrating the issue:

First thing to do, use a newer OPL version (OPL 1.0 should be fine for this test), I don't even remember how GSM was on 0.9.2, maybe it is buggy with some games. Check if the behaviour is the same.

Are you forcing PAL FFX to NTSC?? Why if I may ask? You get some FMVs out of sync that way.

Also GSM disables the flicker filter on FFX, so it is normal to have the image a little more flickery (but also colors are better, just slightly since FFX flicker filter isn't much heavy), indeed using GSM is good on LCD or very stable CRTs (like HD ones).

P.S. Don't use PAL60 it is actually just normal PAL (at 50hz).