CurtPalme.com Home Theater Forum

gholt · Joined: 10 Jan 2007 Posts: 47

Hello. I have 3 Mac Minis connected to 3 Barco 800s (input 5) through Extron interface boxes.

I've recently upgraded my Mac Minis, and now there is a vertical line on the right side of the image on each projector. I've tried eliminating it using blanking, but it didn't work.

Can someone please point me in the right direction for adjusting this?

Thanks in advance!

Ile · Posted: Thu Nov 01, 2012 8:46 am Post subject:

Maybe updating macs have chanced picture timings and now picture is wrapped at right edge.

If this is problem, then adjusting active picture inside raster to left using Hphase (geometry menu) should help. Then move whole raster back to right using raster sift (geometry menu + center convergence for red and green).

gholt · Joined: 10 Jan 2007 Posts: 47

Thanks, Ile. I'm not sure if I'm understanding your instructions. I moved the line to the left side of the picture using the Hphase. That was only a change from 44 to 41. Then, with the raster shift, if I move the raster all the way to one side as far as I can go, I can get most of it out of view, but not quite all of it.

Is that what you meant?

**Curt Palme** · Posted: Thu Nov 01, 2012 5:12 pm Post subject:

Do you have a second projector to try the source on? This definitely is a source issue, and unlike the Marquee, there's no fix for a while line down the side of the screen. Have you tried changing resolutions? Maybe that will at least shift the line outside of the image.

The other option would be to take the lenses off, and put black electrical tape over the line, assuming that it's right at the edge of the image. That will mask it without losing the edge of the image.

gholt · Joined: 10 Jan 2007 Posts: 47

Thanks Curt. I agree that it is a source issue. I have 3 Mac Minis, each attached to a Barco 800 (actually one is an 808). Each is doing the same thing. And the previous, older, Mac Minis weren't causing this. And the Mac Pro that I have on port 3 of the 808 is fine too.

I tried changing resolutions, but it's still there -- just not as pronounced because the convergence is off in the new resolution.

So, you are saying that the Hphase/raster shift won't fix it? Tape is the only option left?

**Curt Palme** · Posted: Thu Nov 01, 2012 9:40 pm Post subject:

I think so. I've seen this in Marquee sets, but not Barcos. It's gotta be some signal artifact that's acting up on the Barco sets. I don't think it cane be cured easily other than the tape method.

Ile · Posted: Fri Nov 02, 2012 7:31 am Post subject:

Sounds like that sources porches are so small that Hphase can't fix this (designed for digital display). You need bigger back and front porch.

Creating custom resolution with bigger porches should help.
http://www.peterkrantz.com/2007/mac-mini-overscan/

Don't use that guys timings, those are for some crazy 1248x680 60Hz display.
Check if you can just ad for example 100 pixel to horizontal back porch to existing 720p (or what ever you are using).

You can use that same window to make some better refreshrate like 71.928Hz (or 75Hz for PAL material).

I use 1080i96 for HD and 768p75 for PAL SD material.

You can google more stuff with "mac mini custom resolution"

gholt · Joined: 10 Jan 2007 Posts: 47

Thanks Curt, and thanks Ile. I'll give Ile's suggestion a try before I go with the tape method. I'm a little worried that the tape might obscure part of the screen on the other inputs.

But as I work toward trying the custom resolution method, what resolution and refresh rate should I be working toward on the Barco 800? I've been running them at 800x600. But I'd love to bump them up to 1024x768 if I can. According to the specs here...
http://www.curtpalme.com/PJSpecs_Barco.shtm
...it looks like it is within that range. And it seems to like a refresh rate of 60.

Ile · Posted: Fri Nov 02, 2012 2:39 pm Post subject:

Some 16:9 resolution would be better than 4:3 these days.

1080i desktop looked bit soft in my 801s, but with movies it was still decent.
1280x720p would be my choise for 800 these days.

60Hz will judder with film based material, because film frame rate is 23.976 Hz.
So 2x or 3x that would be better.

gholt · Joined: 10 Jan 2007 Posts: 47

Thanks again, Ile.
I downloaded DisplayConfigX, but it doesn't work with newer computers. So I found an application called SwitchResX:
http://www.madrau.com
It gives me the same ability to create custom resolutions. I tried increasing the front and back horizontal porches, and it didn't help. But in playing with the Hphase, I think I see what you were trying to have me do, Ile. When I adjust the Hphase right and left, there are positions where I get a much more pronounced line at the right or left edge. And when I center the image, those lines disappear, but I still get a more subtle, but distinct, line on the right side.

I'm using these projectors in a planetarium, so even a subtle line is pretty obvious on a dark dome.

Anything else to try besides the tape?

barclay66 · Posted: Mon Nov 05, 2012 7:16 pm Post subject:

Hi,

I'd try to adjust the blanking settings on each PJ...

Regards,
barclay66

gholt · Joined: 10 Jan 2007 Posts: 47

Thanks barclay66!
Blanking was the first thing I tried. But I don't know if I was only using an internal test pattern, or if I lost my head and only went the wrong way in trying it, but it didn't work. NOW, by using the blanking feature on the right side with this input, I was able to get rid of the line on the right side!

Thanks also to Curt and Ile for your suggestions and time!