[haslip]

I am loving my new HD1000.


I noticed that Comcast Cable and my HD Tivo series 3 has a rough looking top border. Squiggly and such.


Chaning the overscan to 98 or 99 gets rid if it, but as I make the change, I see the entire image get bigger and fill the 720p screen.


The "getting bigger" leads me to believe that the pixels are no longer matched up "pixel to pixel", maybe 700 pixels are redone to 720.


Sounds like this would affect image quality??


Is it better to leave overscan at 100% and let the bad edge go into a black velvet screen border???

 

[EocThermos]

By getting bigger, do you mean it is zooming in or actually going from say, a 104 inch image to a 106 inch? As in are there unused pixels on the top and bottom that are used when you adjust the overscan? (I ask because I recently discovered changing aspect ratio or some such setting from "16:9" to "real" produced this effect.)


It seems more logical that it would zoom in, in which case, yes the pixels are no longer being matched up "pixel to pixel." This is why people use 100% overscan in the first place.


My recommendation is to leave overscan at 100%- but if the bad edge bothers you, try going into the last menu (far right, the one with overscan if memory serves) and down to the lower part of the menu (user settings or something.) You should see an option for shutters (Up, left, right, and bottom). If this isn't grayed out, try increasing the top shutter form 0 to 1- this should solve your problem without cutting off much of the image, and would probably cut out less than the 99% overscan, especially taking into account the sides and bottom are also cut off with overscan.

 

[cavu]



Quote:
Originally Posted by haslip /forum/post/0


Is it better to leave overscan at 100% and let the bad edge go into a black velvet screen border???

Yes.


What you are seeing is the closed caption data stream encoded in the top few lines of the image and is completely normal. On traditional TV sets, this data was off the edge of the screen and few noticed it at all.

 

[Star56]

WHat does the "shutter" setting do on the Mits?


On my NBCHD affiliate, I get a "data" line on the left side of the image. It is off screen...but 99% overscan eliminates it. If I can go with 100% overscan and use shutter this would be great.


Does Shutter degrade the image?



EDIT: Okay I did some experimenting. I set overscan to 100% and then clicked my Hor shutter setting to 1. Bingo! Noise line on the left is gone. Absolutely no negative PQ effect (unlike overscan less than 100%). Very very nice indeed.

 

[EocThermos]

Glad to see it works for you!


For those who may be wondering, the shutter displays a black bar on the specified portion of the screen without altering the rest of the image. It is similar to a computer's crop function. I don't know much each shutter "step" is, but I imagine somewhere between 3-8 pixels.

 

[haslip]

Ah, thank you very much. Yes, shutter is the answer to the problem WITHOUT degrading the image.


It worked, and I am happy.


Scott

 

[one028]

i have the same problem with comcast. i have a section on the top of the screen that has white lines on certain 4:3 broadcasts and commercials that are not 16:9 on high def channels. when i change the overscan to 97% it goes away. when overscan at 100% the white lines reappear at the top of the picture. also if i have the overscan at 100% i get a thin black bar on 16:9 high definition programs, but if i click down the overscan it goes away. if i leave it at 100% and try to move the projector up to have the thin bar and the white lines to go way at 100% i mess up the whole picture position on my screen.


are there some settings im missing. and what does overscan at 97% actualy do to the picture quality?

 

[Star56]



Quote:
Originally Posted by one028 /forum/post/0


i have the same problem with comcast. i have a section on the top of the screen that has white lines on certain 4:3 broadcasts and commercials that are not 16:9 on high def channels. when i change the overscan to 97% it goes away. when overscan at 100% the white lines reappear at the top of the picture. also if i have the overscan at 100% i get a thin black bar on 16:9 high definition programs, but if i click down the overscan it goes away. if i leave it at 100% and try to move the projector up to have the thin bar and the white lines to go way at 100% i mess up the whole picture position on my screen.


are there some settings im missing. and what does overscan at 97% actualy do to the picture quality?

Do not use overscan...it degrades the inage.


Go to the shutter settings..I believe a few clicks below the overscan setting...use the shutter settings to see if you can block the lines.

 

[Y2KFirehawk]



Quote:
Originally Posted by cavu /forum/post/0

Yes.


What you are seeing is the closed caption data stream encoded in the top few lines of the image and is completely normal. On traditional TV sets, this data was off the edge of the screen and few noticed it at all.

Excellent information..... I had no idea what it was!

 

[charlie3133]

But out of the box the Mits is set to 97% overscan (at least mine was nayway) should I increase it to 100 percent or leave it at 97?


I don't currently use the projector to watch tv so I am not worried about data lines but was concerned about tone of the posts above mentioning degrading of the image.

 

[EocThermos]

Set it to 100%. What overscan does, as I understand it, is sort of "zoom in" on the image. It cuts off the the edges slightly, and "zooms in" so that the image still fills the screen. As a result, you are no longer doing 1:1 pixel mapping (not to mention cutting out part of the picture!), and the image will not be as crisp. I think this would be especially noticeable on high def, but I've never tested (mostly because I don't actually have any high def material to test on yet).


As far as *why* it is set to 97% out of the box, my best guess is CRT TV's cut off part of the picture in this fashion, and they probably wanted to copy CRT in that regard. It should be set to 100% regardless.


As was mentioned above, use the shutter setting to take care of the line at the top (closed-caption data stream apparently). Shutter settings are on the far right menu, at the bottom- I believe you need to go under user settings or some additional menu, but I'm not sure of the name of it. It is all the way at the bottom of the 4th menu. Use as little as possible (to avoid cutting off part of the image), just as much as is necessary to cut off the line.

 

[charlie3133]

thank you