Trebors PRO Palettes and Colors Guide with Conversions

[Trebor]

Hoping some may find the following helpful and beneficial...

A7800_PRO_PALETTES_TREBOR_V2021-DISTRO.zip

 

I've put together a variety of palettes for both NTSC and PAL regions.  The variety, in part, distinguishes between colors as they typically appear under a CRT, and colors as they appear under an LCD/modern display.

 

For the CRT palettes, each region contains three considerably different, within reasonable range, hue settings (CRT_V1, CRT_V2, CRT_V3), and the choice between a standard (STD) or bright (BRT) display.  There is relatively less significant variety among LCD/modern displays respecting colors, so only two hue settings (LCD_V1, LCD_V2) with standard (STD) and bright (BRT) options present.

 

Console temperature deltas were taken into consideration, provisioning CRT and LCD palettes with COOL, WARM, and HOT palette appearances.

 

The palette information is presented in three ways:
1. RGB triplet in *.pal format.
2. RGB triplet in *.css format.
3. Hexadecimal in *.css format.

 

A variety of formats allows for incorporation more readily under emulators, as well as implementation under FPGA simulations.

 

The attached zip archive includes various color charts and screen captures from four games.  The captures are grouped together and provided on an individual basis. 

 

Additionally, *.gif files have been created with a one second interval swap showcasing all palettes, just the CRTs, just the LCDs, for both regions.  It makes for easy, quick viewing in seeing if there is significant change for any and all of the 256 possible color values.

 

Double click the images in the spoilers that follow to show their true size.  They are truncated to a much smaller image when just revealing the spoiler.  All images and more are provided in the zip archive at the top of this post.

 

All NTSC Palettes GIF

Spoiler

 

All PAL Palettes GIF

Spoiler

 

Two games (Dig Dug, Commando) demonstrate the differences between display types and their associated hue setting, as well as, standard and bright display options.  There is little change for these titles as the console warms up from the captures provided, so a warm palette is demonstrated only.

 

NTSC Dig Dug & Commando

Spoiler

 

 

 

PAL Dig Dug & Commando

Spoiler

 

 

 

The other two games (Choplifter, Midnight Mutants) demonstrate changes made both with different display types and temperature condition of the console.  They are accompanied by palette charts covering all palette settings provided.  Choplifter focuses on the standard (STD) version of those palette settings and display, while Midnight Mutants is set for the brighter (BRT) setting of the palettes.

 

NTSC Choplifter

Spoiler

 

 

PAL Choplifter

Spoiler

 

 

NTSC Midnight Mutants

Spoiler

 

 

PAL Midnight Mutants

Spoiler

 

 

See the Atari 7800 Color Documentation page under 7800 8BitDev.org for a technical overview, explanation of the consistency issue, and color artifacting, of the palettes: http://7800.8bitdev.org/index.php/Atari_7800_Color_Documentation

 

Last, but not least, the same NTSC palettes are applicable for the Atari 5200 system.  Both NTSC and PAL palette files can be referenced for the Atari 2600 system, when the proper sequencing and layout is followed and applied.

[Trebor]

Planning to post a series of Retail games with some of their respective color keys and a few accompanying screen comparisons.  Dialogue that follows will touch on what is utilized and possible alternatives if the opportunity to provide better color consistency is present and the reasoning behind it.  In turn, it may assist developers in their color selections, as well as, satisfy any who have curiosities of the matter.  Plus, I think it is fun and interesting.  

 

For the vast majority of the time, we will be leveraging the NTSC version of games with NTSC palette references.  However, the concepts and principles are very much applicable for PAL selections; especially considering for the most part the palettes are very similar with a shift of one hue range between the two regions (I.E. NTSC $3x <--> PAL $4x | PAL $5x <--> NTSC $4x). 

 

First up is CHOPLIFTER:

 

 

SKY would have maintained more consistency appearing blue with the $9x range instead of the selected $8x ($88 --> $98).  Hue $8x, after going higher than the first few luminance levels, can tend to look purple with both a cooler system and even more so when moving from a CRT to an LCD. 

 

GROUND couldn't possibly be dealt a worse selection ($E8) for consistency.  Of all the palette ranges available, $Ex contains the most variance - especially under a CRT.  For a CRT, it tends to start as a definitive green (Cold system), or chartreuse green (Cool system), and transforms to a gold/brown by the time the system is hot.  LCD's go from a bright green to a chartreuse green.

 

Here are some alternatives to maintain a golden brown like appearance at the same luminance level, along with pros and cons:

 

$F8 = Much more consistent (cool, warm, and hot) in the brown/gold range under a CRT; but still appearing greenish when the system is cold.  LCD is going to maintain a green look when the console palette is cold or cool, but warm and especially hot, will provide a tan/gold/brown color.

 

$18 = All the time a consistent gold/brown appearance on a CRT; all the time on an LCD, a bright green or chartreuse green.

 

$28 = All the time orange/brown leaning appearance for a CRT; all the time on an LCD, a brown/gold appearance. 

 

STATUS/BUILDING/FLAG 'RED' $34 works beautifully. Either $34 or $33 is best bet for a consistent red on a CRT.  It could be taken a luminance step or two brighter for the sake of an LCD, but it is going to look and lean more of an orange-red on a CRT.

 

STATUS/BUILDING/FLAG 'BLUE' $80 works beautifully as well.  We're as dark as it gets, so no concern for any purple lean.  $81 could be leveraged as well for a slightly brighter look under an LCD, while still looking very 'true blue' for a CRT.  Of course, $90 or $91 would also work fine. 

[+-^CrossBow^-]

21 hours ago, Trebor said:

Planning to post a series of Retail games with some of their respective color keys and a few accompanying screen comparisons.  Dialogue that follows will touch on what is utilized and possible alternatives if the opportunity to provide better color consistency is present and the reasoning behind it.  In turn, it may assist developers in their color selections, as well as, satisfy any who have curiosities of the matter.  Plus, I think it is fun and interesting.  

 

For the vast majority of the time, we will be leveraging the NTSC version of games with NTSC palette references.  However, the concepts and principles are very much applicable for PAL selections; especially considering for the most part the palettes are very similar with a shift of one hue range between the two regions (I.E. NTSC $3x <--> PAL $4x | PAL $5x <--> NTSC $4x). 

 

First up is Choplifter:

 

 

SKY would have maintained more consistency appearing blue with the $9x range instead of the selected $8x ($88 --> $98).  Hue $8x, after going higher than the first few luminance levels, can tend to look purple with both a cooler system and even worse when moving from a CRT to an LCD. 

 

GROUND couldn't possibly be dealt a worse selection ($E8) for consistency.  Of all the palette ranges available, $Ex contains the most variance - especially under a CRT.  For a CRT, it tends to start as a definitive green (Cold system), or chartreuse green (Cool system), and transforms to a gold/brown by the time the system is hot.  LCD's go from a bright green to a chartreuse green.

 

Here are some alternatives to maintain a golden brown like appearance at the same luminance level, along with pros and cons:

 

$F8 = Much more consistent (cool, warm, and hot) in the brown/gold range under a CRT; but still appearing greenish when the system is cold.  LCD is going to maintain a green look when the console palette is cold or cool, but warm and especially hot, will provide a tan/gold/brown color.

 

$18 = All the time a consistent gold/brown appearance on a CRT; all the time on an LCD, a bright green or chartreuse green.

 

$28 = All the time orange/brown leaning appearance for a CRT; all the time on an LCD, a brown/gold appearance. 

 

STATUS/BUILDING/FLAG 'RED' $34 works beautifully. Either $34 or $33 is best bet for a consistent red on a CRT.  It could be taken a luminance step or two brighter for the sake of an LCD, but it is going to look and lean more of an orange-red on a CRT.

 

STATUS/BUILDING/FLAG 'BLUE' $80 works beautifully as well.  We're as dark as it gets, so no concern for any purple lean.  $81 could be leveraged as well for a slightly brighter look under an LCD, while still looking very 'true blue' for a CRT.  Of course, $90 or $91 would also work fine. 

Choplifter is a great example to demonstrate this. The title screen will also the main difference in the green color from cold to warm up between CRTs and LCDs as well.

 

Xevious is another tricky game as the water on that one will change quite a bit in addition the tan colored roads/paths on the ground between cool and hot console temps.

 

[Trebor]

On 6/28/2021 at 10:15 AM, -^CrossBow^- said:

Choplifter is a great example to demonstrate this. The title screen will also the main difference in the green color from cold to warm up between CRTs and LCDs as well.

Most are familiar with the title screen appearing green in color.  However, even under a CRT, when the console starts cold, it will provide a strong amount of blue in its appearance.  The reason for it is the utilization of $B0 as the title screen background color.  The $Bx range overall has a very strong blue influence when cooler.  As the system warms up, the blue emphasis decreases.  Green ultimately becomes the more dominant influence overall:

 

 

This is a very borderline hue range, straddling the fence between green and blue.  Since the color pot in the console impacts the number of degrees between hue ranges - whereas a console warming up increases that value - as demonstrated above, even the slightest adjustment of 0.5° can play a significant role with a value chosen within this range. 

 

The $Ax hue range experiences something similar, but the blue and green ratios are different.  As shown above, $Bx is more green-blue, while $Ax, shown below, is more blue-green:

 

 

To exemplify both hue ranges in practical usage, if shooting for a turquoise or aqua (I.E. Inky in the Pac-Man line of games) a value of $AA is a very adequate selection.  If looking for a more seagreen or mint end result, $BA would be the better choice. 

 

All of the above is applicable for the PAL region too, just substitute NTSC $Bx --> PAL $Cx and NTSC $Ax --> PAL $Bx and very similar behavior as well as end results will be noticed.

 

As for the Choplifter title screen, a more ideal value would be $C0.  Then, all temperatures (and displays) would always have a consistent 'pure' green demonstrated.  With the selection of $B0 in place, seeing a blue/blue-green title screen is acceptable and expected, definitely for a cold console and a bit warmer.  If a console is showing a blue/blue-green title screen when the system is running for a considerable time, something is awry.

 

On 6/28/2021 at 10:15 AM, -^CrossBow^- said:

Xevious is another tricky game as the water on that one will change quite a bit in addition the tan colored roads/paths on the ground between cool and hot console temps.

Indeed.  It is already planned for breakdown and review down the road.

[Trebor]

BASKETBRAWL:

 

 

SKIN TONES utilizing the $1x range - $11, $14, $16 is a great choice and range for the intended original display type.  The $1x range appears as gold/golden range in appearance for CRTs, having darker, brown tones at the lower end of the luminance scale.  Unfortunately, LCDs/modern displays show this hue range as being in the green family - whether it's a 'true' green or more chartreuse leaning.  A couple of alternate options in this kind of scenario include:

 

-Replace $1x values for $Fx values = Under a CRT, when the console is cold, skin tones will appear greenish.   When it is cool and warm, it will appear just like or very similar to the $1x selections.  When the console's palette runs hot, the colors will change up somewhat looking a bit red-orange.  Under an LCD, skin tones will appear green still while cold and cool.  When warm, and even more so when hot, it will achieve that golden brown/tan objective.

 

-Replace $1x values for $2x values = Under a CRT, under all temperatures, everything is going to lean orange looking in appearance.  Under an LCD, a browner/gold appearance will be demonstrated under all temperatures.

 

GREEN SHIRT utilizing the low-mid end of the $Dx range is a good choice.  Under a CRT though, once the system is hot, the $Dx hue range of green picks up a considerable amount of yellow, which makes it more chartreuse appearing than a pure green.  Instead of $Dx choices, going with $Cx ($D3, $D5 --> $C3, $C5) at these low-mid luminance levels, maintains a true green throughout all console temperatures.  For an LCD, the point is moot.  The $Dx range does not pick up the same amount of yellow influence, leaving both hues ranges $Dx and $Cx, at this low-to-mid end of luminance, appearing near exact to one another.

 

BLUE WINDOW pretty much maintains a relatively consistent appearance.  At the lower end of the $8x range being used here - $80 and $83 respectively, there is no danger of acquiring a more purple look as the console warms up.  The $9x range would perform similar if leveraged instead, overall appearing a bit lighter and brighter for the same luminance values.

 

WALL BRICKS appear as intended under a CRT whether brighter or darker, brownish-red or reddish-brown, $10 for the majority and $21 for the outline, serve quite well here.  LCDs once again are suffering with the mishandling of intent and color within the $1x range.  Especially at this lowest luminance of $x0, the lack of red to brighten up the wall makes it appear nearly black on an LCD with standard brightness.  Brighter modern displays will fair better with seeing the wall, but it is really an ugly mess when compounded with the greenish skin tones of the players.  A compromise to this solution could be:

 

-Replace $10 with $20 and replace $21 with $31.  While $1x range is the real issue with LCDs here, we also need to modify the current outline of $21 proportionally to maintain a similar outlined effect.  As is the case with skin tones, the bricks will acquire more of a slightly orange look with a CRT, but not nearly as much in the case of the aforementioned skin tones, since we are so dark on the scale.   Subsequently, LCDs will be out of the green family and demonstrate that intended reddish brown brick tone look.

[Trebor]

KARATEKA:

 

 

 

PLAYER SKIN with a color selection at the lightest end of the scale, in this case $3F, under CRTs, runs a risk of a washed out look.  A higher contrast or strong bloom effect and it will look nearly as white as the player's clothing.  $3D would work a lot better here. 

 

PLAYER CLOTHING going for a pure white outfit, $0F is the choice.

 

OPPONENT SKIN $3C is a great choice, looking good as a flesh tone color.

 

OPPONENT CLOTHING $CF is picked as almost to balance the scales, so the opponent and player both contain a selection from the brightest possible luminance.  If clothing having a bright neon green color is the mission.. consider it mission accomplished.  Otherwise, a plethora of arguable better shades of green could have been selected.  Nonetheless, it is understandable that perhaps the goal was to really make the enemy pop off from the darker wall and floor area. 

 

PLAYER HEALTH | OPPONENT HEALTH utilizing $4x mid-range is perfect for pink and $7x mid-range is great for purple.  If looking for a deeper/darker purple a mid-range $6x would be an option.

 

SKY color results will vary between display type and console temperature under $8x mid-range values - specifically $89 in this case.  As demonstrated above, it can have a very strong purple lean due to the red ratio amount present.  When going for a true blue, $9x is the safest and most reliable range to pick from.

 

MOUNTAIN LAYERS having pure white snow cap tops, much like pure white player clothing, $0F is the choice.  Choosing from the $Ax family with $A5 and $A0 respectively, for the middle and bottom layers, they do turn greener as the system warms up, but have a strong blue ratio for the majority of the time.  If the goal is to lean green with only a slight touch of blue for the majority of the time, then the $Bx family would have worked better.  Blue the entire time brings us back to $9x family.  Green the entire time would be the $Cx range.

 

A step or two lighter luminance choices may have provided an improved look, bumping both a couple of steps brighter regarding the middle and bottom layers.  Noteworthy too, much like too light of a color being washed out at the highest luminance of $xF, a dark green could have suffered here though.  However, under $A0 there's near equal amounts of blue and green when the system is hot, and more blue than green present the rest of the time, as opposed to a $B0, and especially $C0.  So, indeed $A0 works here as far as not looking (near) black.

 

FLOOR as $32 works for being a type of brick red under a CRT.  LCDs show it a bit darker, more maroon (tad browner) leaning.  If a brighter red floor is intended, $33 or $34 could be leveraged.  Anything higher than $34 and an orange tinge would become apparent at least under a CRT.

[Trebor]

Below are color conversion lists containing the hue appearance of the C64 on the left, to a very similar appearing hue under the Atari 7800 system on the right. Selections provided are based on the original targeted CRT display device:

 

NTSC C64 to NTSC Atari 7800 Color Conversions:

COLOR_BLACK <--> $00
COLOR_WHITE <--> $0F
COLOR_RED <--> $34
COLOR_CYAN <--> $AA
COLOR_PURPLE <--> $67
COLOR_GREEN <--> $C4
COLOR_BLUE <--> $84                                            
COLOR_YELLOW <--> $1D
COLOR_ORANGE <--> $28
COLOR_BROWN <--> $14
COLOR_LTRED <--> $3A
COLOR_GRAY1 <--> $04
COLOR_GRAY2 <--> $08
COLOR_LTGREEN <--> $CA
COLOR_LTBLUE <--> $88
COLOR_GRAY3 <--> $0C

 

PAL C64 to PAL Atari 7800 Color Conversions:

COLOR_BLACK <--> $00
COLOR_WHITE <--> $0F
COLOR_RED <--> $44
COLOR_CYAN <--> $BA
COLOR_PURPLE <--> $77
COLOR_GREEN <--> $D4
COLOR_BLUE <--> $74
COLOR_YELLOW <--> $2D
COLOR_ORANGE <--> $38
COLOR_BROWN <--> $24
COLOR_LTRED <--> $4A
COLOR_GRAY1 <--> $04
COLOR_GRAY2 <--> $08
COLOR_LTGREEN <--> $DA
COLOR_LTBLUE <--> $88
COLOR_GRAY3 <--> $0C

 

Although there are not exact color conversions between the systems, the above provides a respectable compromise and brings the results under the 7800 close to the desired hues from the C64.

[Trebor]

Here we go @-^CrossBow^-...

 

XEVIOUS:

 

 

WATER (LEFT) as an $Ax value it is inevitable to run into the issue demonstrated above.  A cooler system will exhibit the hue bluer, but as the palette warms up, especially hot, it picks up a stronger green look.  If the water was $93, instead of $A3, it would have maintained a consistent blue appearance the entire time. The $D8 highlights in the water is also leveraged in the next area of discussion, so without further ado...

 

GRASS DARK (MIDDLE) and GRASS LIGHT (RIGHT) are so intertwined we will cover them together.  Simply put, $Dx is a warmer version of $Cx.  So warm in fact, it picks up enough red that it takes on a yellow tinge, especially with a hot console.  To keep a consistent green appearance, $C3 and $C8 would have been the better selections, instead of $D3 and $D8.

 

GROUND SHORE-PATCH-PATH utilizes $F9.  The behavior of the $Fx range is as follows:  When the console is cool - also known as the "Factory" setting - Hues $1x and $Fx match.  As the console continuously runs, the palette becomes 'warm' and then 'hot'.  The delta in hue reaches a point where ultimately Fx will match $2x.  In summary, $Fx COOL = $1x | $Fx HOT = $2x | $Fx WARM = Unique (between the appearance of $1x and $2x).

 

Under LCDs, the $1x range unfortunately appears as an unintended chartreuse/green hue instead of a golden one seen under CRTs.  So $Fx values when viewed from a cooler console will look chartreuse/green under an LCD as well.  However, as the console warms up, and ultimately the palette becomes 'hot', it will take on the look of $2x, which even under an LCD there is no green dominance.*

 

Understanding the above, alternatives to utilizing $Fx are as follows:

-Utilize $1x values instead.  For the entire time, the $1x hues appear as the correlating $Fx hues do under a COOL system for the respective display type.

-Utilize $2x values instead.  For the entire time, the $2x hues appear as the correlating $Fx hues do under a HOT system for the respective display type.

 

*

 

A significant difference between a CRT and LCD is often for the same hue and console temperature combination within the ranges of $1x, $2x, $Ex, $Fx, overall, an LCD contains visibly noticeable less red, a CRT, more red.

CRT_V3 & LCD_V2 "WARM"
STD PALETTES EXAMPLES:

 

SOLVALOU having $08 and $0C for the primary colors is enough luminance variance to create a layer of depth look to the ship.  Hue $A6 as a highlight, as similarly noted with the water, will appear bluer when cool and greener when hot.  A more consistent blue would be provided by $96; more consistent green by $C6.

 

TARGET crosshair utilizes $0E, which places it just one step below pure white.  After bloom from a CRT is factored, the difference is likely indistinguishable to most.  The slightly off pure white choice may be noticeable by some eagle eyes viewing from a LCD, but selecting one step down from absolute brightest white is nearly a moot point.

 

The outline of $79 is more interesting. It is among a range of hues and luminance values that may appear considerably to slightly, even subtly, redder or bluer dependent on console temperature and display type.  Regarding this specific hue, $79 looks Wisteria ("very light purple") under a CRT, while the LCD is more Amethyst ("light-medium purple") in color.**

 

**

 

Another significant difference between a CRT and LCD is often for the same hue and console temperature combination within the ranges of $5x, $6x, $7x, $8x, overall, an LCD contains visibly noticeable more red, a CRT, less red.

CRT_V3 & LCD_V2 "WARM"
STD PALETTES EXAMPLES:

[+mksmith]

Very nice thank you Robert ? 

[Trebor]

Below are color conversion details containing NES hue data on the left, to a very similar appearing hue under the Atari 7800 system on the right.  First, a general overview of hue ranges is provided.  It is followed by individual specific values for each hue.

 

Keep in mind data presentation is different between the two systems:
NES = LUMINANCE VALUE FIRST, THEN HUE RANGE
7800 = HUE RANGE FIRST, THEN LUMINANCE VALUE

 

GENERAL [NES Value <--> 7800 Value]:
$x0 <--> $0x
$x1 <--> $8x-$9x
$x2 <--> $7x-$8x
$x3 <--> $6x-$7x
$x4 <--> $5x
$x5 <--> $4x
$x6 <--> $3x
$x7 <--> $2x
$x8 <--> $1x
$x9 <--> $Dx
$xA <--> $Cx
$xB <--> $Bx
$xC <--> $Ax
$xD <--> $0x
$xE <--> $0x
$xF <--> $0x

 

SPECIFICS [NES Value <--> 7800 Value]:

 

$00 <--> $05
$10 <--> $0B
$20 <--> $0F
$30 <--> $0F
$01 <--> $81
$11 <--> $85
$21 <--> $99
$31 <--> $9D
$02 <--> $71
$12 <--> $75
$22 <--> $89
$32 <--> $8D
$03 <--> $61
$13 <--> $65
$23 <--> $79
$33 <--> $7D
$04 <--> $51
$14 <--> $55
$24 <--> $59
$34 <--> $5D
$05 <--> $44
$15 <--> $47
$25 <--> $4A
$35 <--> $4D
$06 <--> $31
$16 <--> $35
$26 <--> $39
$36 <--> $3D
$07 <--> $21
$17 <--> $25
$27 <--> $29
$37 <--> $2D
$08 <--> $11
$18 <--> $15
$28 <--> $19
$38 <--> $1D
$09 <--> $D1
$19 <--> $D5
$29 <--> $D9
$39 <--> $DD
$0A <--> $C1
$1A <--> $C5
$2A <--> $C9
$3A <--> $CD
$0B <--> $B1
$1B <--> $B5
$2B <--> $B9
$3B <--> $BD
$0C <--> $A1
$1C <--> $A5
$2C <--> $A9
$3C <--> $AD
$0D <--> $00
$1D <--> $00
$2D <--> $02
$3D <--> $08
$0E <--> $00
$1E <--> $00
$2E <--> $00
$3E <--> $00
$0F <--> $00
$1F <--> $00
$2F <--> $00
$3F <--> $00

[OldStyle]

On 6/28/2021 at 6:35 PM, Trebor said:

BASKETBRAWL:

 

 

 

@Trebor getting down to the nitty-gritty!  Very nice of you to hash out a comprehensive guide for this.  Cannot help but laugh at the ballers turning into zombies! ?‍♂️

[+-^CrossBow^-]

54 minutes ago, OldStyle said:

 

@Trebor getting down to the nitty-gritty!  Very nice of you to hash out a comprehensive guide for this.  Cannot help but laugh at the ballers turning into zombies! ?‍♂️

The most important part of this entire thread is to demonstrate how much different the 7800 colors look on LCD panels vs CRTs given the way LCDs generate their colors and I think the fact that most LCD tend to have more of one LCD pixel color vs the other colors and this is also why the tinting is so different. 

 

I'm glad Trebor has done this because I've gotten more than a few clients ask me why the colors look off when they get their 7800s back after having a UAV put into it. It is because of LCD just handling the color differently. You can adjust your TV in conjunction with the 7800 to compensate for this a bit. But, it will result in everything else likely not looking right on your LCD and the 7800 not looking right when used with CRTs and other LCDs as well. This is why, unless the color is grossly off when I test them on my PVM via composite, that I do NOT mess with the color trimmers on the 7800 that pass by me. Best to leave them be and just have to explain why they look different when plugging it up and viewing it on a modern display.

 

Tower Toppler is the only game where I think the UAV does NOT help in some way due to how different all the colors end up looking. Even through composite, Tower Toppler will not look right on a UAV.

[Trebor]

22 hours ago, -^CrossBow^- said:

...It is because of LCD just handling the color differently...

Indeed.  While the warm up changes are more of an exclusive characteristic of Atari 2600/5200/7800 consoles, some hue values appearing significantly different on an LCD compared to a CRT is not.  For example, the NES has comparable issues.  This can be seen with Super Mario Bros. sky and the background of Kung Fu, varying from blue to purple, just like we see with Karateka's and Choplifter's sky. Or, as in the case of Dig Dug and Commando, some shades of brown appearing green-chartreuse on an LCD, but contain more red on a CRT..Battletoads level one ground is a good example, cliffside of stage one in Contra is another.

 

A fix for this dilemma is to maintain consistency via hard coded color values for the palette hues instead of generating them.  The Atari 2600 and NES already have such a solution.  Hopefully, future revisions of UAV will follow likewise and perhaps other hardware developers may come forward with providing something similar for the 7800.  Having the ability to choose from three palettes under each region, as explained in the linked 2600 mod, is a great compromise.  Cool, warm, and hot palettes can be made readily available.  The linked NES mod provides selection from three palettes as well.  A passthrough option is also present, allowing the systems to just generate colors as they do normally.

 

When such a video solution is in place, it could leverage the files (data) from the download archive in the opening post, as they provision a reasonable wide range of hue settings, console temperatures, and other palette details in a variety of ways.

[Trebor]

FATAL RUN:

 

 

FIRE/EXPLOSION LIGHT utilizing the $1x range furnishes a beautiful golden appearance that shines on a CRT here.  The LCD mishandles the intent and provides a chartreuse look.  Though not appearing horrible on an LCD, it certainly diminishes from the title screen's intended beauty.  There is no substitution possible, due to the nature of $Fx coupled with the already being utilized $2x in the MEDIUM details of the image.  

 

FIRE/EXPLOSION MEDIUM leveraging the $2x range works beautifully here combined with the brighter $1x selections and darker $3x values.  It performs best under a CRT, losing some of its red 'pop' under an LCD.  There is no substitution that would work better under the structure and layout of the picture.

 

FIRE/EXPLOSION DARK fills out the remainder of color with the $3x range.  It provides the darker, reddest tones and works absolutely brilliantly. As we saw with $2x range, under an LCD, lacking the brighter redder tones results in a duller screen.  The $3x range is without equal, no change recommended here. 

 

Undisputedly, one of the best-looking title screens under the system, in which usage of hue ranges and luminance values were wonderfully selected.  The cars cleverly incorporate the three hue levels of fire and explosion, finalizing it all by wise choices within the grayscale.  Gorgeous under a CRT, and as good as it gets for the modern display, with zero visible impact by console warm-up, this is an instance where everything should remain as is respecting palette selection.

[Trebor]

Below is a conversion chart for the 7800 when selecting a hue value under one region and its closest equivalent under the other region.

 

7800 Hue Conversions Between Regions:

NTSC $1x <--> PAL $2x
NTSC $2x <--> PAL $3x
NTSC $3x <--> PAL $4x
NTSC $4x <--> PAL $5x
NTSC $5x <--> PAL $6x
NTSC $6x <--> PAL $7x
NTSC $7x <--> PAL $8x
NTSC $8x <--> PAL $9x
NTSC $9x <--> PAL $Ax
NTSC $Ax <--> PAL $Bx
NTSC $Bx <--> PAL $Cx
NTSC $Cx <--> PAL $Dx
NTSC $Dx <--> PAL $Ex
NTSC $Ex <--> PAL $Fx

 

NTSC $Fx <--> N/A - Best nearest PAL $2x

 

PAL $1x <--> N/A - Best nearest NTSC $Dx

[Trebor]

POLE POSITION II:

 

 

SKY blue consistency would be better accomplished, instead of utilizing $89, leveraging $99.  The hue range of $8x from mid to higher luminance values, when the console is cooler, leans more purple looking.  Hue range $9x remains bluer regardless of console temperature or display type.

 

SAND hues provision a beautiful golden look when under the original intended display, a CRT.  LCDs mishandle the intended result, so the display ends up with a green pyramid surrounded by green sand. The most dominant hues for this section of the scene are from the $1x range.  Without RGB substitution modification for the hardware, the colors will not look right under a modern display, as the $1x range appears either chartreuse or green.  Alternatives to the $1x range include:

 

-Substituting $1x values for $Fx values = Under a CRT, when the console is cold, the sand will appear greenish.   When it is cool and warm, it will appear just like, or very similar to, the aforementioned $1x choices.  When the console's palette becomes hot, the colors will change further looking a bit orange.  Under an LCD, the sand will appear green while still cold and cool.  When warm, and even more so when hot, it will obtain a more golden looking sand.

 

-Substituting $1x values for $2x values = Under a CRT, for all temperature settings, it will lean orange looking in appearance.  Under an LCD, a gold-like appearance will be demonstrated under all temperatures.  However, some of the intended contrast between colors for the sand are going to be lost here as now all three values would be in $2x range instead of just one.

 

ROAD SIGN having $1E in place, the same principles for the sand, mentioned above, applies here.  For absolute black, $00 is always the right choice.

 

BLIMP WITH SIGN having a $3x value in place, there is no other hue range like it.  Some of the lower end luminance values are best for red ($32-$34).  Starting with $35, the range lightens to more of a red-orange/bright orange result. Displays providing overall darker images may yield it a bit more red looking though.  As it continues with even brighter luminance values, the $3x range will appear salmon-like in color.  For a light gray, $0A is a great choice, and going to $0C gives a nice lighter contrast while not going quite pure white, more off-white.

 

ROAD LINES with $34 being best as possible offering from the color palette for a bright red, it works well here as road lines.  For pure white, $0F is the selection to make and nicely compliments the bright red.

 

AUTOMOBILE selection in the $2x range will remain consistently the same regardless of console temperature.  It loses some of the red influence shown under a CRT when viewed under an LCD.  When the console is hot, the $2x hue range and the $Fx hue range match.  $00 is perfect for absolute black, which makes the tires and highlights of the car.

[Trebor]

*UPDATE*  Palette information is still presented in three different ways: 1. RGB triplet in *.pal format.  2. RGB triplet in *.css format.  3. Hexadecimal in *.css format.  All palettes can be leveraged for the Atari 7800, 5200, and 2600 platforms.  Details are included in the attached zip archive.

 

ATARI_PRO_PALETTES_TREBOR-DISTRO_20211021.zip

 

WHAT'S NEW..

1. File names updated: A7800_ --> ATARI_
2. REG and EVN palette sets added. 
3. OPT, NAB, and TLS bright palette variations added.
4. DRK, WAB, and LST dark palette variations added.

 

DETAILS..

Palette File Names = "ATARI_'REGION'_XXX_YY_ZZZ-TTTT.pal"

 

'REGION' = Console type

-NTSC
-PAL

 

XXX = Display type palette interpretation:

-CRT = Palette colors as demonstrated under a typical traditional display (CRT).
-LCD = Palette colors as demonstrated under a typical modern display (LCD, OLED, Plasma).

 

YY = Hue setting interpretation:  

-CRT contains three versions..  V3 and V1 hue lean slightly red and green respectively, relative to V2.
-LCD contains two versions..  V1 leans slightly less green than V2.

 

ZZZ = Overall display settings interpretation:

-LST = Dark with less saturation.
-WAB = Dark and rich with no pure white.
-DRK = Dark and rich.
-STD = Dark with even color ramp.
-EVN = Balanced with even color ramp and darker grayscale.
-REG = Balanced with even color ramp and lighter grayscale.
-OPT = Bright with even color ramp.
-BRT = Bright and vibrant. 
-NAB = Bright and vibrant with no absolute black.
-TLS = Bright with less saturation.

 

TTTT = Console temperature interpretation:

-COOL = Console powered on for a few to several minutes.
-WARM = Console powered on for more than a few to several minutes.
-HOT =  Console powered on for a longer period of time.

 

Examples:

-"ATARI_PAL_CRT_V3_NAB-WARM.pal" = PAL console CRT color interpretation with a slight red hue lean that is bright and vibrant with no absolute black under a warm console.
-"ATARI_NTSC_LCD_V2_BRT-COOL.pal" = NTSC console Modern display color interpretation that is bright and vibrant under a cool console.

 

Recommendation:

-Start with.. CRT_V2_EVN-WARM.

[+sramirez2008]

@Trebor The Palette Whisperer.?

[+Muddyfunster]

I'm actually half tempted to add LCD and CRT/Emulation colour modes to my games. That or avoid the problematic ranges all together.

[Trebor]

12 hours ago, Muddyfunster said:

...avoid the problematic ranges all together.

PAL 2600's did just that, though the 'jumping around' hue order sorting may make it harder to discern.  Still, there are no $1x, $Ex, $Fx, hues available as they appear under PAL 7800.  Those ranges were swapped with grayscale repetition.  That is why the system palette has the same grayscale range, four times.  What should be just one hue $0x range and the aforementioned three hue ranges with colors 'muted'.

 

PAL 2600 $0x = PAL 7800 $0x
PAL 2600 $1x = PAL 7800 $0x
PAL 2600 $2x = PAL 7800 $2x
PAL 2600 $3x = PAL 7800 $Dx
PAL 2600 $4x = PAL 7800 $3x
PAL 2600 $5x = PAL 7800 $Cx
PAL 2600 $6x = PAL 7800 $4x
PAL 2600 $7x = PAL 7800 $Bx
PAL 2600 $8x = PAL 7800 $5x
PAL 2600 $9x = PAL 7800 $Ax
PAL 2600 $Ax = PAL 7800 $6x
PAL 2600 $Bx = PAL 7800 $9x
PAL 2600 $Cx = PAL 7800 $7x
PAL 2600 $Dx = PAL 7800 $8x
PAL 2600 $Ex = PAL 7800 $0x
PAL 2600 $Fx = PAL 7800 $0x

 

Or the same thing grouped another way:
PAL 2600 $2x = PAL 7800 $2x
PAL 2600 $4x = PAL 7800 $3x
PAL 2600 $6x = PAL 7800 $4x
PAL 2600 $8x = PAL 7800 $5x
PAL 2600 $Ax = PAL 7800 $6x
PAL 2600 $Cx = PAL 7800 $7x
PAL 2600 $Dx = PAL 7800 $8x
PAL 2600 $Bx = PAL 7800 $9x
PAL 2600 $9x = PAL 7800 $Ax
PAL 2600 $7x = PAL 7800 $Bx
PAL 2600 $5x = PAL 7800 $Cx
PAL 2600 $3x = PAL 7800 $Dx

 

PAL 2600 $0x = PAL 7800 $0x
PAL 2600 $1x = PAL 7800 $0x
PAL 2600 $Ex = PAL 7800 $0x
PAL 2600 $Fx = PAL 7800 $0x

[Trebor]

*UPDATE* 

ATARI_PRO_PALETTES_TREBOR-DISTRO_20211129.zip

 

WHAT'S NEW..
-Added accidentally excluded "REG" palette files.
-Removed erroneous duplicate set of "STD" palette files.

 

Additionally, with the official latest release of the 7800 MiSTer core, a streamlined (*.pal files only) version of the above archive has been submit for the repository.

[Trebor]

*UPDATE*

ATARI_PRO_PALETTES_TREBOR-DISTRO_20220318.zip

 

WHAT IS NEW..
-Addition of "ATR" & "RTA" palette files.

 

-In conjunction with the above new palette files, easier to follow palette sorting by folder:

 

\\(1) Display Type Colors Imitation\(2) Overall Picture\(3) Saturation Amount\(4) Hue Setting

 

(1) CRT or LCD
(2) Bright or Dark
(3) Saturation 1 (least) - Saturation 4 (most)*
(4) CRT V1,V2,V3 or LCD V1,V2**

 

*For Saturation 3 and Saturation 4, there are alternative choices, located in the Alternatives folder.

 

**CRT_V2 or LCD_V2 is recommended as the hue start point for their respective display type:
    -CRT with less red push, try CRT_V1; CRT with less green push, try CRT_V3.
    -Try LCD_V1 for modern display interpretation containing less green push.

 

As done previously, a streamlined (*.pal files only) version of the above archive update has been submitted for the Atari7800_MiSTer repository.

[+wavemotion]

@Trebor thanks for your diligent work on this!  I went through a large number of your palette files for A7800DS and, despite the DS having an LCD, I found the CRT V2 'bright' Sat-2 set to look best on the DS handheld.   I'm giving the user the option of three palette choices - COOL, WARM (default) and HOT.  So far I'm pretty happy with WARM across the board with a few games that I prefer COOL.

[Trebor]

7 hours ago, llabnip said:

@Trebor thanks for your diligent work on this!  I went through a large number of your palette files for A7800DS and, despite the DS having an LCD, I found the CRT V2 'bright' Sat-2 set to look best on the DS handheld. 

You're welcome! The palette "CRT" and "LCD" designations are indicative of color interpretation if taking the original native console and viewing on either the respective modern (LCD) or traditional (CRT) display. 

 

By far, CRT palettes will furnish best results as most modern developed games, and certainly all original retail titles, were viewed under a CRT, or/and those color interpretations are the intended and desired ones.  The LCD palette can aid developers in discerning how the colors chosen will appear under that particular display condition.  Of course, this thread helps furnish side-by-side comparisons and better understandings as well.

7 hours ago, llabnip said:

I'm giving the user the option of three palette choices - COOL, WARM (default) and HOT.  So far I'm pretty happy with WARM across the board with a few games that I prefer COOL.

For the most part, the WARM palette is the best compromise with a few arguably even appearing at their best (I.E. Scrapyard Dog).  Some games the temperature is practically irrelevant and not even worth distinguishing the difference (I.E. Dig Dug).  Other games certainly show COOL as preferable (I.E. Galaga, Joust).  While HOT, really makes some other games shine their finest (I.E. Choplifter!, Midnight Mutants, Ikari Warriors).   

 

For A7800, we left WARM as the default, with COOL and HOT available too.  Atari7800_MiSTer FPGA follows a similar pattern with the added bonus of the ability to load external palette files.

[Trebor]

*UPDATE*

TREBORS_ATARI_PRO_PALETTES_V2-DISTRO.zip

 

What Is New [Differences from ATARI_PRO_PALETTES_TREBOR-DISTRO_20220318]:
-Improved duplication of hue temperature behaviors, most noticeably for NTSC Hue 10 & Hue 11 | PAL Hue 11 & Hue 12.
-Fine adjustment to midrange hues.
-Simplified display output selections and default saturation.
-Better brightness balancing and simulation logic.
-Added palette phase shifts among COOL (25.7), WARM (26.7), and HOT (27.7); COOLPLUS (26.2) and WARMPLUS (27.2).

 

Utilization...

\\(1) Region\(2) Console Brightness Output Simulation\(3) Display Hue Output Simulation\(4) Palette Temperature

 

(1) NTSC | PAL
(2) AV (Modern A/V Mod Output) | BAL (Balance between AV and RF) | RF (RF Output)
(3) CRT | CRTALT | LCD | LCDALT
(4) COOL (25.7) | COOLPLUS (26.2) | WARM (26.7) | WARMPLUS (27.2) | HOT (27.7)

 

Palette information is presented in three ways:
-RGB triplet in *.pal format.
-RGB triplet in *.css format.
-Hexadecimal in *.css format.

 

A variety of formats for easier incorporation under emulators, flashcarts, and FPGA simulations.

 

Palette Samples (COOL | WARM | HOT):

 

NTSC CRT RF...

 

PAL CRT RF...

 

NTSC CRT AV...

 

PAL CRT AV...