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English Lake District, Buttermere, looking west from the shoreside at Dalegarth toward Mellbreak and Crummock Water.

November 2017

 

A view inspired by classic Japanese prints.

 

Fells in view (from left)- on left: lower slopes of Red Pike, Hen Comb, very summit of Blake Fell; central: Mellbreak; on right: Rannerdale Knotts, lower slopes of High Snockrigg.

 

Co-ordinates of viewpoint: 54.52996,-3.25864

Map of area in view: https://osmaps.ordnancesurvey.co.uk/54.54589,-3.29418,13

output_1.png

drpeter_Buttermere_Pine.xex

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2 hours ago, a8isa1 said:

You might be surprised to learn that my NTSC palettes exist because I was attempting to get Altirra's colors to look like my real 800 with a scan converter and a CRT VGA monitor.  They are intentionally wrong.

 

Decades ago I read an Atari 800 field service note that describes adjusting the color trim pot so that hue 1 and hue 15 appear equal on the screen.   That's how my 800 stands to this day.  I eventually learned that this type of adjustment was incorrect.  However, I have no way to accurately put any of my Ataris back to the factory setting.

 

Moving years ahead to the release of some version of Rastaconverter.    Since my 800 is out of adjustment then the colors rendered in picture conversions of course would not align.  To my surprise there wasn't a position for the pot that would make the colors align. 

 

I assumed my 'scan converter' (basically a cable TV set-top box designed for a desktop computer) and CRT monitor combo were way off the mark with respect to the NTSC specification. 

 

I decided to view Rastaconverter picture on emulators only.

 

Some time later I learned that I could adjust Altirra's colors to resemble my real Atari.  This in turn got me to wonder if I used the now custom Altirra palette in Rastaconverter if the colors might look correct on my 800XL (by this time the 800XL was my daily driver).   The colors were considerably better.  Almost totally aligned.  I tweaked the hue starting color and hue angle.   My palettes are set where I stopped tweaking.   Atari Blue-green and cyan(ish) hues still don't seem to line up correctly.  The other colors are very close. 

The saturation levels in the palettes don't affect what a real Atari can output but they subtly affect choices made by Rastaconverter during the processing.

 

-SteveS

 

On my 800, which I just got a year ago, and have used it little until my upgraded 1200XL went down for repairs, and the colors on games I know well were sometimes wrong, compared to my PAL 1200XL or even to it when it was still NTSC and also before that when I owned a NTSC 130XE. They were wrong with the CPU card that came with the computer, which I recently replaced with a NOS from MyAtari, and the colors were still wrong with it's glued factory settings too. Mainly the issue is with green and brown colors. Two examples are the opening Lucasfilm title screens on Lucasfilm games that are green instead of the normal brown and gold shades and the mountains in RoF are green instead of brown. And Blue Max 2001 which should have a red/brown landscape background is also green. I couldn't get them to their normal colors using the trim pot without screwing up all the other colors. I have it back to factory now.

 

I do use a S-video to VGA converter for my LCD screens. My LCD screens won't pick up the 800's chroma signal connect via composite, or with my video to HDMI converter, only the Ambery VGA converter picks up the chroma signal, but it can work with anything PAL/NTSC and even mixed. I hope to have my 1084S monitor repaired soon, if I can find the time. I've got a dozen large electronic projects and little time to finish them. Mostly requiring time-consuming trouble shooting. But the colors were accurate with the converter for my PAL 1200XL.

 

I think that 1 and 15 hue adjustment is only for PAL computers, as they technically only have 120/240 colors since those hues are the same on PAL. They are not the same on NTSC so you get the full 128/256 colors. But most trim pots have brightly colored (usually pink/orange) glue where the factory fixed their settings, and all you have to do is line those back up, this requires opening it up to see, rather than adjusting through a case hole of course.

 

I purchased a PAL CPU board for my 800, and plan on converting my 1200XL back to NTSC, but I am waiting until I get my Incognito to replace the CPU card, since I don't have a PAL OS board, and no sense it buying one with Incognito on the way. The 800 will become my main computer once the Incognito arrives, since it'll have twice the memory of my 1200XL, and I want my main computer to be PAL for far more software compatibility. 

Edited by Gunstar

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Buddy- you're a young man. hard man
Shoutin' in the street- gonna take on the world some day
You got blood on yo' face
You big disgrace
Wavin' your banner all over the place

(singin')

We will, we will rock you...

output_4.png

drpeter_FreddieMercury.xex

 

41 colours

Edited by drpeter
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This thread is really interesting as time goes on.  You can almost see a style of each person's pictures, even though they are automated conversions.  I noticed this when drpeter started posting.  Very cool!

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On 10/15/2019 at 6:07 PM, Stephen said:

This thread is really interesting as time goes on.  You can almost see a style of each person's pictures, even though they are automated conversions.  I noticed this when drpeter started posting.  Very cool!

As Gunstar has noted, there are many subtle judgements and not a little skill involved in setting up, running and selecting the conversions that end up being posted, automated though they are- not least the selection of the original image.

 

I suppose you could obliquely liken it to photography, where after the pressing of the shutter button, the internal workings of the camera are entirely automated.

 

It's everything that comes before & after that which is the main determinant of the quality of the image (in every sense) and which leads to a recognisable individual 'style'.

 

As Gunstar has also noted (and also like photography) it takes time, trial and error, practice and the help of an artist's eye to learn the craft.... 

 

I'm still feeling my way, and enjoying developing my 'style' 😄

 

For example, on a purely technical level, I do things differently from Gunstar as I increasingly iteratively pre-process images alongside making changes to RastaConverter's parameters until I'm happy with the pre-process preview and introduce masks either from the start or when there seems a repeated tendency for the conversion to go in an unwanted direction.

Edited by drpeter
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2 hours ago, drpeter said:

As Gunstar has noted, there are many subtle judgements and not a little skill involved in setting up, running and selecting the conversions that end up being posted, automated though they are- not least the selection of the original image.

 

I suppose you could obliquely liken it to photography, where after the pressing of the shutter button, the internal workings of the camera are entirely automated.

 

It's everything that comes before & after that which is the main determinant of the quality of the image (in every sense) and which leads to a recognisable individual 'style'.

 

As Gunstar has also noted (and also like photography) it takes time, trial and error, practice and the help of an artist's eye to learn the craft.... 

 

I'm still feeling my way, and enjoying developing my 'style' 😄

 

For example, on a purely technical level, I do things differently from Gunstar as I increasingly iteratively pre-process images alongside making changes to RastaConverter's parameters until I'm happy with the pre-process preview and introduce masks either from the start or when there seems a repeated tendency for the conversion to go in an unwanted direction.

I too, like that each person's style can shine through, and I noticed right away that you have a very different style than I, definitely a good thing in my opinion. I like to limit my pre-processing to just good picture cropping and ratio so that every image I do can use the maximum amount of screen area and I downsize my images to 320x240 using the Lanczos algorithm from the i_view64 app instead of using the Lanczos or other algorithms built-in to Rastaconverter, then just leave it on the default 'box' filter of Rastaconverter. Other than that, I do everything else within Rastaconverter, with the exception of not using masks because I like the challenge of getting the best result I can without masking. If there is a repeated tendency for a conversion to go into an unwanted direction, I prefer to just adjust the palette, color distance, color correction and once in a while dithering to avoid that tendency. I do this because I have found in my own personal experience that if I use masking to concentrate on an area the area around that masked area degrades in an unwanted direction.

 

I like your photography analogy because one can have the best camera in the world, but without an artists/photographers eye and skill at setting up the subject matter before taking the photo the best camera in the world will still give you bad photos without proper lighting, perspective/angle, centering the subject matter, etc. I even hate the auto-focusing and exposure/light adjustments of modern digital cameras as it rarely works as well for me than manually focusing and manually adjusting the shutter speed for exposure. No computer assistance can make up for a good artist/photographer's trained eye.

Edited by Gunstar
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This will be my last NTSC conversion because it is just too much work trying to get good images out of Rastaconverter for NTSC machines, besides extra pre-conditioning to capture the correct aspect ratio, I still find I have continual problems with NTSC palettes, no matter which I use, with green colors showing up where it should be black or grays (when viewed on real Atari machines) it's just too much of a headache for an already tedious process. I'll have a PAL machine up and running within a few weeks again anyway, and just go back to that, which I prefer for the full 240 lines of resolution.

 

I'd normally have kept working on this one, as it's not up to my usual personal standards I strive for, but when greens screw it up anyway, what's the point?

 

Tempest side art. 70 colors.

TempestSideArt.png

TempestSideArt.xex

Edited by Gunstar
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On ‎9‎/‎21‎/‎2019 at 9:54 AM, drpeter said:

Kanagawa-oki nami ura

 

Woodblock print by the Japanese ukiyo-e artist Hokusai.

Published ~1830 as the first print in the series Thirty-six Views of Mount Fuji

 

40 colours

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drpeter_Kanagawa.xex 21.93 kB · 42 downloads

Among the best fits I have seen for the Atari display, and it shows crisp and very well defined on my analog-to-digital video path.

 

It is worth mentioning, however, that I remember seeing a very similar version but showing a bit different in real life (at least as I remember it when being en-route to Bora Bora, and stopping by Tahiti, where they have a museum there showing it):

 

Waves-1.thumb.jpg.16e7a8f13fcd622a22ca451256bfdd0d.jpg

 

I wonder how the above one would look like rasta-processed, though...

 

Cheers!

 

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On 10/17/2019 at 5:00 PM, Faicuai said:

I remember seeing a very similar version but showing a bit different in real life

Being a woodcut print of some vintage, the appearance of any one print today will vary depending on a variety of factors: the inks and paper chosen and how they have interacted and degraded over time during display and storage, how the ink was spread and blended on the blocks, the printing technique and alignment of the blocks used for different colours (with some random variation), variation in any by-hand drawing or touching-up done after the print.  In some cases, there may also have been more than one set of blocks made, or replaced over time.  There are for example significant variations in the exact patterns in the waves seen in different examples of this print in galleries around the world.

 

Furthermore, there have been at least 4 stages of digital image processing involved in producing my image: the original photograph, post-processing before posting on the Web, pre-processing and cropping in preparation for Rasta and finally the Rasta conversion itself.

 

On 10/17/2019 at 5:00 PM, Faicuai said:

 

Waves-1.thumb.jpg.16e7a8f13fcd622a22ca451256bfdd0d.jpg

 

 I wonder how the above one would look like rasta-processed, though...

 

Something like this 😉

 

It's not a perfect conversion yet, I'm still working on it...

 

 

 

output_3.png

Edited by drpeter
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1 hour ago, Irgendwer said:

Experts know that this is the only acceptable A8 version:

L35_Katsushika_Hokusai_8.png.dbbe6a1bfd72bdf924ce8ddafd3ad329.png

 

😄

Not sure what "experts" know  about a 240x240 pixel image with 5 gradients of colors that point to a 16 bit color palette.

The picture in post #2237 looks much more fitting to the Atari.

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12 minutes ago, Irgendwer said:

Finally you got it!

 

You mean, I got it that you always can handle only parts of a sentence?

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It's a joke, if I am not wrong it's a level from Irgendwer's nice game Dye😄

 

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I got the joke, just didn't remember where it was from, even though I reviewed DYE in EXCEL, but it has been two years. Just commenting on Emkay's reply.

Edited by Gunstar

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On 10/17/2019 at 3:45 PM, Gunstar said:

This will be my last NTSC conversion because it is just too much work trying to get good images out of Rastaconverter for NTSC machines, besides extra pre-conditioning to capture the correct aspect ratio, I still find I have continual problems with NTSC palettes, no matter which I use, with green colors showing up where it should be black or grays

 

I see the same issues - my PAL conversions look fairly color accurate, and appear the same (or close) in Altirra versus hardware. My NTSC ones look good with a couple of the palettes distributed with Rasta, but then can look bad in Altirra, and sometimes even further bad on hardware. I also get greys that go green and it looks like luminance in general may be off depending on the conversion palette I used.

 

I've been meaning to pick apart the palettes that come with RastaConvert; it seems almost probable given the issues that there just ISN'T a good NTSC palette - the authors may not even have had access to hardware. So I was going to make my own, but I need to find in the code what the format is - does anybody know to save me the trouble, is it just 444 or 888? Or better yet does somebody have a custom NTSC palette they find consistently good with Rasta?

 

Of course, even the actual hardware had a lot of variance on NTSC. It wasn't nicknamed "Never Twice the Same Color" by chance. However I've never seen early vs. late Atari hardware turn grey into green.

 

 

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if your hardware, whether it be old NTSC or next gen NTSC is calibrated and is matched to your television or monitor, it will always be the same color unless there is a power supply replacement or degradation involved. Drift from a signal transmitted from 150 miles away doesn't exist in this setting.

 

If you have an issue where the color are never the same twice... you have issues in your television or broadcast station. It's great that people like the artsy fartsy acronym association- but it has little to do with the reality of closed circuit NTSC. PAL had a myriad of problems in it's first couple incarnations. Folks really need to read about all of this... rather than latching on to such things.

Edited by _The Doctor__
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47 minutes ago, _The Doctor__ said:

If you have an issue where the color are never the same twice... you have issues in your television or broadcast station. It's great that people like the artsy fartsy acronym association

It's a...joke. About a what, 60+ year old analog broadcast standard. It's really not expected to be perfect in the first place, and I'm sure somebody had an equivalent saying for PAL.

 

The reference to hardware drift in color was regarding the atari hardware, which most definitely changed in color output for a given value in different incarnations (and not just between CTIA and GTIA, for instance XL and XE have slightly different color tone). And to be fair, not an NTSC issue, more of an Atari one.

 

 

Edited by gnusto
remembered the date for NTSC wrong =)

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Yes the topic is fairly well covered, being a part of those conversations can make the brain hurt... I modified my XL's to shift more towards the XE for Jingle disk... looks much better that way. I think I even pointed out a capacitor involved at some point in time. ;)

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10 hours ago, gnusto said:

 

Of course, even the actual hardware had a lot of variance on NTSC. It wasn't nicknamed "Never Twice the Same Color" by chance. However I've never seen early vs. late Atari hardware turn grey into green.

 

Yes, for years those in PAL land have made fun of NTSC in this way, but that's why our TV's also have/had tint control, but this could be set differently by different companies at the factory too, so one could walk into a show room and every brand looked different. But from my years of experience, every brand could be matched too. And I always liked being able to adjust the tint. Especially when playing PAL games that worked on NTSC back in the day, like Mastertronic titles that made it to the US, and English Software company too; mostly through mail order in Antic/Analog magazines, I don't recall coming across English Software titles where they sold Atari software in the US. 

 

But in this case, changing the tint or adjusting the pot on your computer isn't going to fix the problem, just change the color of what is still supposed to be Black and grays. And though I am having "color issues" with my 800 that I'm not used too, having been mostly an XL/XE user for years, I also have a green problem with it. However it's not turning blacks and greys green like Rastaconverter NTSC palattes, stuff that I am use to having a brown/yellowish color (depending on the lumanence of the color) are greens instead, but if I adjust the pot on the CPU board, all the other colors go out of alignment. I'm not worried about it though, as I have an Incognito board arriving soon, and when it does I have a PAL CPU board I'm installing at the same time on my 800, and my PAL converted 1200XL I will revert to NTSC. Now I suppose my 800's color issue could be that I'm using PAL versions of games that have NTSC versions (like Rescue on Fractalus having green mountains instead of brown, and the Lucasfilm titles on all their games being green instead of the brown and gold I'm used to seeing) but there's no distinction when downloading files from software archives.

 

 I've also tried using custom palette's that @a8isa1 has created, that you can download from a link in his posts. And though with one of his palette's, I was able to get rid of the greens in the Darth Vader "Dark Reflections" image I posted (that weren't meant, some where in that image), but after that, with every image I tried to convert I got the "false greens" no matter the NTSC palette.

Edited by Gunstar

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