Combat PAL vs NTSC differences
A week ago I bought my first atari 2600 on ebay, I got a light switcher with a (tatty) boxed copy of combat. I never owned an atari 2600 but I had played a couple games on an emulator so I knew what they'd look like, especially combat with its light brown sandy color, so you could imagine my surprise when I pop in my combat cart, hit reset and the game screen is mostly a vomit green. What is this? I've played this game a few dozen times, I should be blasting tanks on a desert, not a football field! On and off for a week I searched this forums and the internet in general and the only thing people advised was adjusting the colour pot. I must've adjusted that potentiometer a dozen times before I gave up, I'd rather shoot tanks on a grassy hill than on a pink field, that just wouldn't do. Next I tried adjusting the tiny little pot on the RF modulator and while it did give me a cleaner more stable picture, the colours still weren't right. Americans can ignore this since I believe the small pot is a PAL thing only.
I remembered reading about PAL and NTSC differences on the go deeper than the refresh rate like in most other consoles and after a little digging I found this page which says that different regions have a different number of colours available and therefore different palettes:
PAL - 104 colours
NTSC - 128 colours
SECAM - 8 colours
The difference in colours between PAL and NTSC isn't that great, but the guys in SECAM regions really got shafted. After this I downloaded PAL and NTSC roms of combat and tested them in an emulator.
PAL is on the left and NTSC is on the right
Game 1
Game 6
Game 15
Game 25
(Note that the PAL images are bigger than their NTSC counterparts, this is not an error, PAL and SECAM ataris have 100 more scanlines but run 12% slower. In most PAL consoles the opposite happens, but the framerate is still 12% slower than in NTSC regions)
As you can see, the palette differences in some games are very striking, in game 1 there are the already mentioned differences of the brown vs green but the tanks are also different colors, in the NTSC version the tanks are red and blue(such patriotism) and in the PAL regions the tanks are a pastel baby blue and pink which when displayed over aerial almost look like the same colour which makes it a little hard to distinguish which player you are, at least to me, but I'm slightly colourblind so YMMV.
Game 6 also has a completely different pallet, but this time I think the blue background looks much nicer than the weird red shade they chose for the NTSC version. The tanks are also different, but this time the it's easier to distinguish the PAL tanks.
Game 15 is almost unchanged although the colours in the PAL version are a little bit brighter which makes the NTSC version look slightly better in my opinion.
Game 25 is where the NTSC version completely drops the ball, why is the magenta? And why are the clouds green? It makes no sense! This time the PAL version gets the edge with a navy blue sky and gray-ish clouds.
And just for fun, here's what game 1 looks like in SECAM regions, with a neon green background, pink borders and black and white tanks, this really is the ugliest version of the game, I really feel sorry for the French.
So that's it for the differences between PAL and NTSC combat, now I know that my atari isn't messing up the colours. Now if only I could get sound that isn't just static...(I suspect this is because I'm in a PAL B region and my console is PAL I).
Thanks for reading.
Sources:
Spiceware
Chinavasion
AtariPreservation
Screenshots captured with z26 emulator