Green Tones while in Greyscale... Quadra 700

[Opardalis]

I just wanted to rule-out a more serious issue, but on my Quadra 700 (base 512k VRAM), using my adapter and LCD, I'm getting 640x480, but there is a heavy green tone. Oddly, even if I switch to greyscale, I still have the green tone.

Same adapter/LCD works well on many other Macs, so I'm assuming its just the wrong pin setting on the adapter, I have to find the manual with all the pin codes.

Just wanted to rule out a more serious issue with the motherboard. I have seen some posts about adapter settings causing green tones, just never though it would occur under greyscale.

 

[commodorejohn]

It sounds like what happens when a monitor that isn't expecting a sync-on-green video signal gets one. Not all of them handle this correctly by separating out the sync signal from the actual green signal, so you get exactly this effect - I had the same thing with my SGI O2 on one monitor and had to use a different one that knew what to do. Though that doesn't explain why you'd see this only on one particular Mac...huh.

 

[Alex]

 Oddly, even if I switch to greyscale, I still have the green tone.

I know this might seem obvious but if another computer is connected does the green symptom reported persist? If not then proceed with examining the pin issue otherwise consider the source of the issue as the display itself.

 

[aladds]

Though that doesn't explain why you'd see this only on one particular Mac...huh.

Some Macs (IIsi springs to mind) require Sync on Green, and others don't, so I can understand that only certain computers are exhibiting this behaviour.

 

[Quadra]

I have had a greenish screen connecting an IBM 15" lcd to a Q700. Trying different adapters and settings didn't help. A Viewsonic 15" lcd gave no problems though.

 

[ktkm]

I hade same issue with my “Apple Macintosh Display Card 670, 820-0600-A” in an IIcx connected to an EIZO LCD monitor. 

This i what the Swedish EIZO support said:

“Synch on Green is only used to boot the screen and has nothing to do with green image. Check your settings so that the graphics card is reset to default settings. There may be any setting that is made and draws the color to green. The screen should have no problem receiving the analogue signal supplied from Card 670.”
 
Then, I actually managed to calibrate the Monitor to work with 670 card by using the monitor settings.
 
/ktkm