2600 color anomalies

[EightiesMan]

In 2008, my 2600 cartridges were exposed to mold in my unfinished basement when my father attempted to air it out by opening the windows. I cleaned them as best I could with alcohol on Q-tips. I played them with the VCS adapter on my 5200 system and the colors of some games now appear to be off. In Ms. Pac-Man, for example, the blue background on the first two boards is now green.

 

In October, I bought an original 2600 console for the first time, a four-switch CX2600A. I play it on a 40" Westinghouse HD monitor, straight into the RF input with an RF adapter, no switchbox. I also set the 5200 up the same way. Colors on the 5200 cartridges appear to be unaffected.

 

The colors on the 2600 seemed to be okay for the most part, certainly different than on the VCS adapter as I remember growing up with (in particular, they seem to be less saturated). However, I noticed that the green ghost on Ms. Pac-Man seemed to be smeared or poorly focused, especially on the black title screen. The blue maze walls on boards three and four also appeared to be more of a light purple/gray than blue. Green and blue, in particular, on other games, also had smearing/focus problems.

 

I adjusted the chroma pot slightly counterclockwise, to the point that the ghost was no longer smeared, but now the blue background on boards one and two is as green as it was on the VCS adapter, despite the fact that the maze walls on three and four are now a bit more blue, not to mention slightly blurry.

 

Other games have had similar blur problems with certain colors after the adjustment; Yars' Revenge, in particular, which I only recently bought; its white lines are somewhat out of focus and not as sharp as they once were.

 

Most significantly, before and after the adjustment, pure reds are dusky and dark, almost maroonish at times, nothing like the screen captures I've seen.

 

Another problematic game is Asteroids: the graphics seem to have horizontal lines going through them, the asteroids in particular, and the firing cannon.

 

What could be the problem here? Is it possible that the graphics of the game cartridges themselves were affected by my cleaning or the mold exposure? Is the VCS adapter off-set? Or is this a chip problem? Is it worth tracking down cartridges in better shape?

 

I'd greatly appreciate any feedback. Thanks.

[alex_79]

Another problematic game is Asteroids: the graphics seem to have horizontal lines going through them, the asteroids in particular, and the firing cannon.

This is a problem with your TV, not the console or games: like most digital TVs, yours is treating the signal from the 2600 as interlaced, merging two consecutive frames from the console into a single one and then applying a deinterlacing filter. This is most visible in games that use a steady 30Hz flicker (like asteroids), but all games are affected to some extent (fast moving objects will look blurred, for example).

Edited January 21, 2018 by alex_79

[Thomas Jentzsch]

You can try to disable all picture "optimizations" and (if your TV has it) "game mode" (or similar). Sometimes this helps.

 

But most modern TVs are not designed to display old video game formats. They simply cannot handle the 240p format and use 480i instead, resulting into all kinds of negative effects on picture quality.

[EightiesMan]

This is a problem with your TV, not the console or games: like most digital TVs, yours is treating the signal from the 2600 as interlaced, merging two consecutive frames from the console into a single one and then applying a deinterlacing filter. This is most visible in games that use a steady 30Hz flicker (like asteroids), but all games are affected to some extent (fast moving objects will look blurred, for example).

 

Thank you so much. Now I don't have to worry about getting another cartridge. I do have a '90s CRT monitor somewhere in the house that still works. Think I'll use that for Atari gaming.

[EightiesMan]

You can try to disable all picture "optimizations" and (if your TV has it) "game mode" (or similar). Sometimes this helps.

 

But most modern TVs are not designed to display old video game formats. They simply cannot handle the 240p format and use 480i instead, resulting into all kinds of negative effects on picture quality.

 

Did that. Put everything on standard mode with no enhancements. Looks like it's just the TV. Glad anyway that these HD screens can play vintage games at all, but it's certainly disconcerting to see these errors after over thirty years.