Output Resolution

[Paul Breen]

Hey all, im in the middle of setting up an LED wall & floor system with the 2nd output from Catalyst being sent directly to the processors. My issue is that when the mac desktop is on its fine, but with full screen out (1st output local, second 1280x1024@60Hz) the far left edge line of pixels aren't being displayed. No data is being received to it. With the software open and no fullscreen its fine, just full screen on output 2. I can't shift the position of the LED across so it's something I need to sort on the catalyst end.
Any ideas?

[Mr_P]

Does this still happen after a total power down and re-start?
Have you tried changing the resolution in the OS, then start catalyst?
Does a resolution / refresh rate change make a difference?

There are so many LED screens that start at 0 pixel - and don't have any way of offsetting the start pixel...

One workaround would be to use a scan converter on the DVI output and shift the image back by 1 pixel.

S

[Paul Breen]

Yes, no matter what the image is the same. Only catalyst, no matter what resolution/refresh. I found this post though which describes similar

"
Hi there

I have a strange problem... i have to output 1024 pxl to a led screen... When i show the desktop in the led screen then everything is okay but when i start the catalyst up i´m missing the first collum of pixels...(1 og the 1024).. I have tried everything with and without pixelmix and it is the same deal..

Anyone??

Best Regards


Thomas" to which Richard replied
"its an apple bug - sometimes on some version of os etc - there is a mis-alignment between screen values and underlying coordinate values-

i need to put an option in preferences to switch between different alignments."

My conclusion is that it's just one line of pixels, and only myself and the guys setting up the system noticed it. The way I would do it if it were my screen would be to shift the screens across but the system the guys have means physically taking out each panel to address them 32 pixels right, which for like around 400 panels is just too much for one line, there is no software to control overall position, just addresses. I may just get a scan converter and do it that way but it's such a small thing that it won't make any difference.

[Mr_P]

I've sen the same thing myself - and not been able to fix it in software. But it does differ between graphics cards and servers...

I've not found an option/preference to adjust this in recent software builds...

I think the scan converter option might be the only way to go if its an issue.

S