NTSC core for VBXE?

[leech]

Here is a picture comparing the 800xl (NTSC) and 130xe (NTSC with VBXE, default palette).

If I can get the palette loader to work, will post more pictures.

 

Edit: okay in order we have 1) normal VBXE palette.   2) the AltirraDefault and 3) AltirraC1702 one.

 

Both seem too dark.  Also to clearify, the left is the 800xl connected via composite.  On the right is the 130xe with SCART out the VBXE.

 

Edited July 15, 2020 by leech

[leech]

1 hour ago, DrVenkman said:

Okay, well as a starter for discussion for NTSC folks, here's what I did. I started up Altirra and used the menus to select its default NTSC colors (View --> Adjust Colors ...). I then exported the palette as a .PAL file. Next I loaded this .PAL palette into Atari800 and then saved it as an .ACT file. I then set Altirra to NTSC + Commodore 1702 monitor. This is much more saturated (maybe too much so) but it's at least an option to consider. I went through the same steps to get an .ACT file. 

 

NTSC Default:

 

 

NTSC + C1702 Monitor:

 

There are several other presets available in Altirra plus infinite adjustability. Personally, I'd be happy with either of the above and I'm not strongly wedded to either. 

 

 

AltirraC1702.act 768 B · 1 download AltirraDefault.act 768 B · 1 download

I wonder why those came out so dark on my system.  Maybe I should muck with the brightness, though it seems correct for the most part. 

 

The above post of mine was done by using the vbpal from http://mono.i-demo.pl/ which I put onto an ATR, which I then loaded from the SD-Max (as of course mounting it directly on the SIDE2 makes it try to boot, which then it just gives me a boot error... so I booted into SpartaDOS and ran vbpal <filename> to load the palette, then I reset and went into the SIDE Loader to load the ACP program.).

[+DrVenkman]

3 minutes ago, leech said:

I wonder why those came out so dark on my system. 

That’s why I used Altirra screenshots rather than photos of a CRT. Too many variables in monitor brightness/contrast and potential saturation settings, let alone camera exposure and processing ... 

[leech]

1 minute ago, DrVenkman said:

That’s why I used Altirra screenshots rather than photos of a CRT. Too many variables in monitor brightness/contrast and potential saturation settings, let alone camera exposure and processing ... 

Yeah, I was thinking about feeding it through capture cards.  Though I am using the 1084s 'default' settings.  (As in the nobs are all in the middle part where it kind of clicks into place).  But if you look at the first 'default' picture of the VBXE, the colors are definitely brighter.

[+DrVenkman]

1 minute ago, leech said:

Though I am using the 1084s 'default' settings.

Sadly, that’s not a guarantee of anything with a decades-old CRT. How many hours are on the tube/how worn are the phosphors? How old are the caps on the power and neck boards? What are the settings of the R/G/B gain and bias controls inside on the neck board, and when we they last calibrated? How is the internal flyback transformer Screen control set? Etc. Not to mention that every brand and CRT, regardless of age, will have some variability in how it’s going to compare to the next.

 

Which, again, is why I decided to post screenshots from abstracted “idealized” palettes in an emulator to get an idea of what they look like, at least as a preliminary point of discussion.

 

 

[leech]

13 minutes ago, DrVenkman said:

Sadly, that’s not a guarantee of anything with a decades-old CRT. How many hours are on the tube/how worn are the phosphors? How old are the caps on the power and neck boards? What are the settings of the R/G/B gain and bias controls inside on the neck board, and when we they last calibrated? How is the internal flyback transformer Screen control set? Etc. Not to mention that every brand and CRT, regardless of age, will have some variability in how it’s going to compare to the next.

 

Which, again, is why I decided to post screenshots from abstracted “idealized” palettes in an emulator to get an idea of what they look like, at least as a preliminary point of discussion.

 

 

Sure, completely understandable.  But, even from the capture card, still looking about the same...  The 1702 palette looks probably the closest to the original.

 

 

Edited July 15, 2020 by leech

[leech]

So I know some like to make sure Star Raiders has the correct color of shields (I couldn't find a screenshot to compare, just the suggestion it should be Dark Gray / Bluish.  So here is my attempt (previously the shields were green with the screenshot of ACP above.)  Now that I've adjusted the pot, the palette does look closer to the ones @DrVenkman had posted.

 

[flashjazzcat]

Sophia dynamically configures itself with an NTSC palette. Why not just ask Simius what he used? I've seen no complaints regarding the Sophia palette.

[bfollowell]

9 hours ago, leech said:

Here is a picture comparing the 800xl (NTSC) and 130xe (NTSC with VBXE, default palette).

If I can get the palette loader to work, will post more pictures.

 

Edit: okay in order we have 1) normal VBXE palette.   2) the AltirraDefault and 3) AltirraC1702 one.

 

Both seem too dark.  Also to clearify, the left is the 800xl connected via composite.  On the right is the 130xe with SCART out the VBXE.

 

OK, there's so many screens, I really can't make heads or tails of what we're looking at.

 

Just to clarify. Going down we're seeing options 1, 2 & 3, and left & right, the Commodore monitor and the Samsung TV, we're seeing 800XL and 130XE, right?

 

If so, then the VBXE palette on the 800XL doesn't look anything like the real VBXE output on the 130XE nor does the AltirraC1702 palette. Also, VBXE and AltirraC1702 palettes look pretty close on the 800XL, but the AltirraDefault palette looks completely different than the other two and not all that different from the actual VBXE output on the 130XE. Also, the VBXE and AltirraC1702 palettes on the 800XL look way too green, though I'm not sure if that's normal or not.

 

[bfollowell]

7 hours ago, leech said:

So I know some like to make sure Star Raiders has the correct color of shields (I couldn't find a screenshot to compare, just the suggestion it should be Dark Gray / Bluish.  So here is my attempt (previously the shields were green with the screenshot of ACP above.)  Now that I've adjusted the pot, the palette does look closer to the ones @DrVenkman had posted.

 

 

I know there's a lot more involved that just the color of the Star Raiders shields, but I also know that's a quick and easy check for many of us, and they do look much better here than I'm used to seeing with a PAL palette.

[bfollowell]

3 hours ago, flashjazzcat said:

Sophia dynamically configures itself with an NTSC palette. Why not just ask Simius what he used? I've seen no complaints regarding the Sophia palette.

 

That's true. While I'm missing artifacting with my Sophia DVI, the image quality and the colors always seem to be spot on. Simius is usually pretty quick to respond to questions. This sounds like an excellent idea. If noting else, it may give us another, and possibly better, palette option.

 

[+DrVenkman]

2 minutes ago, bfollowell said:

 

That's true. While I'm missing artifacting with my Sophia DVI, the image quality and the colors always seem to be spot on. Simius is usually pretty quick to respond to questions. This sounds like an excellent idea. If noting else, it may give us another, and possibly better, palette option.

 

Will one of you who have been in contact with him before reach out and ask his input? (And while you’re at it, ask if he has a timeframe yet for Sophia 2 - my 1088XEL has been waiting for a Sophia since forever and I finally have something coming for it - eventually! ). 

[leech]

7 minutes ago, bfollowell said:

OK, there's so many screens, I really can't make heads or tails of what we're looking at.

 

Just to clarify. Going down we're seeing options 1, 2 & 3, and left & right, the Commodore monitor and the Samsung TV, we're seeing 800XL and 130XE, right?

 

If so, then the VBXE palette on the 800XL doesn't look anything like the real VBXE output on the 130XE nor does the AltirraC1702 palette. Also, VBXE and AltirraC1702 palettes look pretty close on the 800XL, but the AltirraDefault palette looks completely different than the other two and not all that different from the actual VBXE output on the 130XE. Also, the VBXE and AltirraC1702 palettes on the 800XL look way too green, though I'm not sure if that's normal or not.

 

The 800xl is stock and used for reference.  But I messed with the POT afterward, so it actually should be more accurate now.  I even managed to get Gold color on the Ballblazer intro screen, which apparently is also a quick calibration method.  But I think my capture device adds its own bit of artifacts to the screen, as it seemed greener there.

 

So yeah, when you say way too green.. the 800xl is stick.  I did tweak the lot so it should be less green now (the shields were green)  I will take another picture from the tube later.

[+DrVenkman]

10 hours ago, phaeron said:

Might consider the 'NTSC Contemporary' profile as an alternative to the C1702 profile. The latter is an older profile that was made before I implemented color primary correction and has a high amount of blue boost to try to make up for it. The NTSC Contemporary profile uses color correction instead and is a bit 'softer'.

 

Also, I would double-check these palettes on an existing VBXE before asking for a new core bake. The palettes are specified in sRGB, but I don't know if anyone has verified that the VBXE RGB output has similar gamma. I'm guessing that it should with a VGA output, but you never know. If there is a gamma discrepancy then a transform will be needed on the color values.

 

Thanks for your insights, Avery. Much appreciated!

 

Unless someone does it before then, I’ll create an “NTSC Contemporary” .ACT palette file this afternoon - I’ve been fortunately to be able to work from home throughout the pandemic but that means I gotta make hay while the sun shines, as the saying goes.

[leech]

3 minutes ago, DrVenkman said:

Thanks for your insights, Avery. Much appreciated!

 

Unless someone does it before then, I’ll create an “NTSC Contemporary” .ACT palette file this afternoon - I’ve been fortunately to be able to work from home throughout the pandemic but that means I gotta make hay while the sun shines, as the saying goes.

Same here (the work from home bit).  Cool, I can test it out.

 

My screen captures, by the way were created via VBXE -> SCART -> OSSC -> USB3HDCAP and OBS, then snagging it via the Windows screenshot utility.

The 800xl images I tried to swap between s-video and composite.  But outside of the single wire for adding Chroma, it has zero modifications.

[candle]

just a note here

you're discussing hue and luminosity over camera shots or screen caputers of unknown and uncalibrated displays through web browser, various phases of image enchancments, monitor settings and driver settings on each individual computer you use for browsing this forum

any conclusive palette will be probably of least liking to any of you

i would go with Avery mathematical model of what NTSC should look like and live with it, or - don't know what else - but this is the reason discussion on forums over shades of blue is pointless

 

[+DrVenkman]

7 minutes ago, candle said:

i would go with Avery mathematical model of what NTSC should look like and live with it

That is exactly why I was using emulator screenshots from Altirra as my sample images. It’s a convenient baseline, easily reproducible by anyone who launches the emulator and sets the color options listed. The very same issues of monitor calibration, camera settings, a person’s own sensitivity to color, etc will also affect PAL color palettes.

 

So it just seems best to me to pick a good theoretical model of what NTSC “SHOULD” look like and then let us adjust our own monitors and displays to suit personal preferences - which is pretty much what PAL VBXE users have done anyway, right? 

Edited July 15, 2020 by DrVenkman
typo

[candle]

i have little demands for Atari palette - if green is green, not blue and i can distinguish all shades of given color i'm happy - this is not DTP work station after all

 

[leech]

52 minutes ago, DrVenkman said:

That is exactly why I was using emulator screenshots from Altirra as my sample images. It’s a convenient baseline, easily reproducible by anyone who launches the emulator and sets the color options listed. The very same issues of monitor calibration, camera settings, a person’s own sensitivity to color, etc will also affect PAL color palettes.

 

So it just seems best to me to pick a good theoretical model of what NTSC “SHOULD” look like and then let us adjust our own monitors and displays to suit personal preferences - which is pretty much what PAL VBXE users have done anyway, right? 

Yeah, the deep problem of the Ataris has always been, not all NTSC output is created equal.  Though I must say, I can freely recommend that Samsung Syncmaster 910MP to any retro computer enthusiast, I've been very happy with it (has SCART even, for a TV that can be used in the US, that's rare, though you have to put it in UK mode...).

If we have the actual RGB values they're supposed to be, I can calibrate the monitors to be the correct color (through Emulation or whatever) as I do have a Spyder5Pro.  I'm more curious about color representation of everything.  My original pictures really were kind of crap, but was mostly just to see a quick difference.  I also had to recalibrate those colors on the 800xl since then.  But I think at least I finally hit that sweet spot on that machine.

 

But I'm happy to test these on the actual VBXE in case Altirra's output isn't quite what the real hardware does.

[+DrVenkman]

Okay, at @phaeron's suggestion, this is Altirra's NTSC Contemporary pre-set. Once again, I exported the palette, imported it to Atari800, then exported it as an .act file.

 

 

I like this one quite a bit. If @Simius doesn't have a better suggestion (such as the one he uses for Sohpia), I'd vote for this one. 

NTSC_Contemp.act

[Mr Robot]

stick it in the vbxe with vbpal and see how a few of the usual suspect games look

 

[bfollowell]

2 hours ago, DrVenkman said:

Okay, at @phaeron's suggestion, this is Altirra's NTSC Contemporary pre-set. Once again, I exported the palette, imported it to Atari800, then exported it as an .act file.

 

 

I like this one quite a bit. If @Simius doesn't have a better suggestion (such as the one he uses for Sohpia), I'd vote for this one. 

NTSC_Contemp.act 768 B · 2 downloads

 

3 minutes ago, Mr Robot said:

stick it in the vbxe with vbpal and see how a few of the usual suspect games look

 

I agree with both of you. I think that image looks great! I also suggest checking it out with a few known suspect games. I’d also suggest waiting to see if Simius has any input. I’ll try to see if I can get a message out to him when we get back to our rental this evening.

 

[+DrVenkman]

50 minutes ago, bfollowell said:

I also suggest checking it out with a few known suspect games.

Well, testing on real hardware with both CRT and LCD output simultaneously, my E: text background is blue not aqua or teal, Star Raiders has blue shields rather than green, Pitfall II has the proper shade of blue between the trees, which are the correct shade of brown ... Any other titles I should look at quickly that you guys can thing of off-hand?

 

[Mr Robot]

I'm in the same boat as @Stephen re colour-blindness

[+DrVenkman]

2 hours ago, Mr Robot said:

I'm in the same boat as @Stephen re colour-blindness

If anyone besides me, @leech and @bfollowell have a VBXE in an NTSC machine, they have yet to speak up.