Atari 7800 video too greenish

[phoenixdownita]

I performed the composite mod to my 7800. I bought it used and the RF never worked.

While playing Joust I noticed the platform to be more greenish than I remember. I checked the 800/XE version and there they are more yellow.

is there anything that can be done to "fix" the greenish hue that appears to be a little overdone?

 

Mine looks exactly like this http://www.youtube.com/watch?v=qKAzDIMOKy0 ... see how green the platforms are?

I was expecting something more like this http://www.youtube.com/watch?v=s2q2X1XIQsg (the 800/XL port) in terms of coloring, also playing with an emulator rendered the platform much closer to the 800/XL than my actual 7800.

 

Any info/help greatly appreciated.

[Trebor]

What type of display are you viewing your 7800 on...Is it a CRT or LCD/LED/Plasma?

 

The Atari 7800 brown/tan/yellow-ish colors for Joust as well as games like Commando will appear too greenish on modern displays.

 

Example here:

http://atariage.com/forums/topic/206923-ntsc-color-palette-crt-tv-default-tuning-varieties/page-2?do=findComment&comment=2699592

 

If you only have a modern flat panel display to play your 7800 on, you will need to adjust the tint/hue (Typically 'counter-clockwise', 'negative', 'to the left') at least partially, if not fully, to come closer to how the colors should/would appear on a CRT.

[phoenixdownita]

What type of display are you viewing your 7800 on...Is it a CRT or LCD/LED/Plasma?

 

The Atari 7800 brown/tan/yellow-ish colors for Joust as well as games like Commando will appear too greenish on modern displays.

 

Example here:

http://atariage.com/forums/topic/206923-ntsc-color-palette-crt-tv-default-tuning-varieties/page-2?do=findComment&comment=2699592

 

If you only have a modern flat panel display to play your 7800 on, you will need to adjust the tint/hue (Typically 'counter-clockwise', 'negative', 'to the left') at least partially, if not fully, to come closer to how the colors should/would appear on a CRT.

 

It's an LCD, I will give it a shot on a small CRT I kept around to make sure there it looks fine there as a starting point.

 

When you say "adjust the tint/hue" do you mean from the TV controls or is there a pot on the motherboard of the 7800 that I can tweak?

I'd like to do it at the source so I won't have to mess up with my TV settings every time I connect the 7800.

 

[thanks for the link to that post, it seems temperature is also a factor .... how is that possible? Is Maria sensible internally to temperature changes? If it is due to outside components it should be possible to replace all of them with much precise ones these days for pretty cheap and with better temperature characteristic]

[Trebor]

I mean the television controls. Most modern TV's retain the different adjustments for each input. So, if you adjust the hue for your composite input it shouldn't affect the settings for HDMI, component, etc.

 

The internal pot adjustment (Closest to the cart port) will adjust the amount of blue against green or red. From what you are showing in the examples, I do not believe that is the issue. This appears to be a classic case of how the 7800 appears on an LCD compared to a CRT.

 

Warm-up ("temperature"), or phase shifting is not as dramatic for most as the difference between LCD vs CRT especially in a short/smaller window of consistent system run time. Also, on an LCD, the phase shifting may appear almost non-existent due to it's overall heavier lean towards green, as seen in the link I posted in my previous response.

 

Focusing on phase shifting overall, like in the game Joust as the example, it will impact the color of the birds wings (E$) over time the most. They will go from a strong green to a 'olive' green, to finally a brown if your system phases more heavily. The overall browns/tan of the platforms (1$) will remain consistent throughout the system's running time. Again, this will be more clear and evident on a CRT, and may not be as noticeable on a LCD.

 

In summary, phase shifting most noticeably will be seen to impact greatly a few row of colors (Although all are impacted to a degree) over a long(er) period of consistent system runtime, but your display type (CRT vs Flat Panel) immediately impacts colors with the most evident being the amount of green over tan/brown/gold.

 

Respecting replacing or swapping out components to try and prevent (Or at least minimize) phase shifting, some would argue that phase shifting is better - and indeed it is for newer titles (Commando, Ikari Warriors), as opposed to the more classic ones (Joust, Galaga), which look best with the colors phase shifting less.

[ApolloBoy]

Have you tried adjusting the color pot inside the 7800 itself?

[phoenixdownita]

Well according to Trebor above it may not help at all and given those pots are supposed to be touched very rarely I'll probably have to let it as it is and stomach the green.

I can't really change the hue on my TV either as I have many consoled connected to the same AV input thru a mechanical switch box and to fix the 7800 I will mess all the rest.

 

Oh well, at least I know it's "expected" ... it is the first console to be doing so ... I also have an XEGS and that one does not seem to have the issue with the green.

[ApolloBoy]

Just try adjusting the color pot, it won't hurt anything.

[Stun Runner 87]

Edited September 25, 2013 by Stun Runner 87

[Trebor]

Oh well, at least I know it's "expected" ... it is the first console to be doing so ... I also have an XEGS and that one does not seem to have the issue with the green.

The Atari 2600 will behave in a similar fashion, perhaps not as drastic though. I posted recently the following in another thread coincidentally:

 

Here's an example, utilizing the status bottom part of the screen in Solaris.

The entire background color as well as the fuel display will come across more greenish on a HD/Flat Panel display:

http://youtu.be/WY2LrUjSpN0?t=49s

 

Now here is the same on a CRT:

http://youtu.be/buhHMAcRSwU?t=3s

 

This CRT has the saturation bumped up a bit, but still a very brown and gold combo:

http://youtu.be/f68IjW7_w98?t=6s

 

While the phase-shift will account for some of the green(er) or brown(er) being evident on a CRT or HDTV respecting the overall background color. The fuel display remains a greenish color on a HD/Flat Panel, while more golden-tan on a CRT.

[ColecoGemini]

This is why I keep a CRT in my game room. I have the LCD for PS3 and Genesis, but keep the CRT for the 7800, 2600 and SMS.

 

There is a way to lessen the greenish hue on 7800 composite modded out put, by adding a bridging resistor between the outputs if a coupl of resistors on the luma ladder. I'll see if I can post pics of my custom mod later.