My Mac's black point is too high

[beau 1664876222]

I use a Mac G4 with Panther OS and a Mitsubishi "Diamond" display. I

do exclusively b&w images.

 

Recently I noticed something changed in my display: it's as if

someone moved the "black point" up significantly. All the darkest

tones just look black. It's not just photoshop, it's every image

displayed on the monitor. The images look bright and saturated, and

yet everything dark falls off into black. I'm not sure, but the same

thing may be happening at the other extreme -- near-whites falling

into pure white too quickly.

 

I don't have real calibration tools, but I've tried messing with

everything I can think of, and no luck. When I use the standard

Macintosh calibration steps, the first brighness adjustment "target"

is jet-black even with the brightness and contrast at 100%.

 

Does anyone know what's going on? I'd appreciate any suggestions.

[beauh44]

Hi Beau, By the way - great name! ;-) I don't own a Mac but if you can beg, borrow or (temporarily) steal another monitor, that would go a long way telling you if the problem is indeed in your monitor or not. Obviously if another monitor has the same problem, then yours is probably fine and the glitch is likely in your display card. Conversely you could take your suspect monitor to another Mac and see how it does. We used to call this "diagnosis by swap-tronics". Good luck!

[seth_prince]

The Macintosh website is agonizingly slow but I've found thier discussion board to be

extremely usefull

 

http://discussions.info.apple.com/

[testingname]

Or recalibrate:

System Prefs --> Displays --> Color --> Calibrate

[beau 1664876222]

Matt,

 

As I said, the recalibration is hopeless, because no matter what I do on the monitor's controls, the black/gray calibration target remains pitch black.

 

I think it's either a software incompatibility that somehow got into the system or a problem with my video card.

 

Does anyone know how to revert to the default monitor drivers and profiles in Panther?

[kirk_thompson]

As Matt said above, under System prefs>Display>Color, you can find the list

of available monitor profiles & change from one to another: if you have an

image in the background, you can see the change immediately. And you can

delete a profile you don't want from Library>Colorsync>Profiles>Display.

 

Did you by any chance just upgrade to Panther .3?

[beau 1664876222]

Kirk,

 

No matter what I do in System prefs>Display>Color, the problem remains -- every variation I try fails to separate the dark tones into different shades. None of the profiles seem to get at the real issue. When I make everything super low-contrast, the bottom three squares of the wedge look the same shade of gray. It's as if the black point is raised _before_ the image gets to the various utilities that are supposed to control it.

 

Panther .3 might be what brought on the change -- do you know about a bug that causes this? If so, I'd appreciate a more detailed description.