| Author |
Message |
Aaron Inami
Joined: 08 Apr 2008
Posts: 17
|
| Posted: Wed Jun 03, 2009 12:19 am Post subject: 1920x1080 image folding into itself on side harmful? |
|
|
I have a Barco 1208/2. When displaying a 1080p @ 48Hz image everything is fine. However, when I try to display an image with 1080p @ 60Hz, the image/test pattern is folded into the active video area on the sides. This is exactly what has been posted before:
I just popped in my Digital video essentials disc with a 1920x1080 grid to check the convergence with a source as opposed to a gen locked pattern, and I was surprised to see that the 1080 pattern was 'folded' in the active video area...but still in the normal raster. If i use H Phase I can see that the grid is too large for the active video area, and can move it about left or right to see it 'unfold'...you can actually see it fold back on itself only on the right of screen, at the left it just disappears.
I can kick 1080p60 into high-scan mode by using the adjusting pot on the vertical deflection board, but at high-scan mode, my projector cannot hold vertical control more than a few minutes. After a few minutes, the vertical control is lost and the image becomes bent/warped from left to right (almost like a center skew and bow being out of adjustment at the same time). I am thinking that this is due to a component on the vertical board or even SMPS that cannot hold the current/heat for long and needs to be replaced (like a bad cap or mosfet or something). It's on my list to rebuild the SMPS and vertical board, so I'm hoping this will solve my problem.
While I investigate this, I would like to know if it's harmful to the projector/circuit/tube to have the image folded onto itself on the left and right sides of the video. I can display 1400x1050 @ 60Hz, but 1920x1080 is just too wide for low-scan mode.
|
|
| Back to top |
|
 |
kal
Forum Administrator
Joined: 06 Mar 2006
Posts: 18114
Location: Ottawa, Canada
TV/Projector: JVC DLA-NZ7
|
| Posted: Wed Jun 03, 2009 1:28 am Post subject: Re: 1920x1080 image folding into itself on side harmful? |
|
|
| Aaron Inami wrote: | | While I investigate this, I would like to know if it's harmful to the projector/circuit/tube to have the image folded onto itself on the left and right sides of the video. I can display 1400x1050 @ 60Hz, but 1920x1080 is just too wide for low-scan mode. |
It's only harmful if the raster goes off the tube surface. But then you don't want the image to wrap around at all as it would look odd.
Kal
_________________
Support our site by using our affiliate links. We thank you!
My basement/HT/bar/brewery build 2.0
|
|
| Back to top |
|
|
Aaron Inami
Joined: 08 Apr 2008
Posts: 17
|
| Posted: Wed Jun 03, 2009 5:53 am Post subject: |
|
|
|
Thanks! We're only talking about a few inches of distortion on each side of the screen and I have been able to get it so that it doesn't actually wrap around (by tweaking H-Phase). The video is definitely not going onto the side of the tube and is staying completely within the raster, so based on what you have said, I'm safe.
|
|
| Back to top |
|
|
kal
Forum Administrator
Joined: 06 Mar 2006
Posts: 18114
Location: Ottawa, Canada
TV/Projector: JVC DLA-NZ7
|
|
| Back to top |
|
|
Mark_A_W
Joined: 15 Mar 2006
Posts: 3068
Location: Sunny Melbourne Australia
|
| Posted: Wed Jun 03, 2009 10:22 pm Post subject: |
|
|
It sounds like you are using a PC, or a VP.
If so, you can add more horizontal porches pixels till the problem goes away.
On a PC you use Powerstrip to do this (or maybe the Nvidia custom res tool).
|
|
| Back to top |
|
|
NewbieDAN
Joined: 09 Mar 2006
Posts: 319
Location: Bunbury Western Australia
|
| Posted: Fri Jun 05, 2009 3:01 am Post subject: Re: 1920x1080 image folding into itself on side harmful? |
|
|
| Aaron Inami wrote: | I have a Barco 1208/2. When displaying a 1080p @ 48Hz image everything is fine. However, when I try to display an image with 1080p @ 60Hz, the image/test pattern is folded into the active video area on the sides. This is exactly what has been posted before:
I just popped in my Digital video essentials disc with a 1920x1080 grid to check the convergence with a source as opposed to a gen locked pattern, and I was surprised to see that the 1080 pattern was 'folded' in the active video area...but still in the normal raster. If i use H Phase I can see that the grid is too large for the active video area, and can move it about left or right to see it 'unfold'...you can actually see it fold back on itself only on the right of screen, at the left it just disappears.
. |
Sounds like my quote Aaron 
The only way I could resolve this was to pass my HD-DVD 1080p/60 signal through my Video processor....which I had to upgrade (VP50) to get control over the video width whilst not in high scan mode....Going into High scan mode with the 1209s resolved the image width/folding on the left with 1080p/60 content with no video processor in the video chain....BUT introduced shocking "Raster Ringing"...something which the VP50 tamed.
I suppose my experience is that if you want to get the best out of your display, and are sensitive to visual anomolies (or are just anally retentive) you need to introduce some processing into your video chain. The VP50 has a number of other benefits, and there are plenty of other processors capable of custom scan rates and primary color tweekability. My Barco Graphics 1209s 9" projector is a very capable piece of gear, but requires processing to get the best out of it.....and isn't that why we're all here?
Dan
_________________
Sorting the fly sh*t from the pepper
|
|
| Back to top |
|
|
|
|
