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Full Setup Guide

 

Overscan, Underscan, and 1:1 pixel Mapping

 

Introduction

[spoiler]Underscan is where the image from the computer has a black border around it on the tv

Overscan is where the image from the computer extends beyond the edges of the tv

0% overscan is where the image from the computer perfectly touches the edges of the tv

1:1 pixel mapping is where 1 pixel on the computer corresponds to 1 pixel on the tv

Most tvs if not setup correctly will overscan (zoom) the image from the computer, so you can't see the edges.

 

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For picture quality 1:1 pixel mapping is the most important.

For being able to see the whole image without wasting any pixels we want 0% overscan.

 

Pixel Mapping is the most important, with most TVs you will get 0% overscan with 1:1 pixel mapping, on some TVs you may be missing a 1-2 pixel on the left/right/bottom, so even though you have 1:1 mapping you technically have a tiny amount of overscan/underscan, however you wouldn't want to correct for this because then you loose your 1:1 pixel mapping. If you are missing a pixel or two, don't correct for this in MP screen calibration, leave the pixels off the edge of the screen.[/spoiler]Underscan: Desktop doesn't reach the edge of the tv.

Overscan: Desktop extends beyond the edge of the tv.

 

Your desktop resolution should already be set to your display's native panel resolution.

 

Full HD 1080P TV: 1920x1080 resolution

HD Ready TV: Consult tv manual/manufacturer for the native panel resolution, and also read "Notes for other displays"

Computer Monitor: Don't need to worry about pixel mapping or overscan, see "Notes for other displays"

 

How to check if you have 0% overscan and 1:1 pixel mapping

 

Download overscan.test.patterns.zip

Run TigerDave.exe, this will display the test pattern in full screen with 100% zoom.

The arrows should touch the edge of the screen

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If you put your eyes right up to the TV you should see straight even 1 pixel width lines

All the lines should be exactly the same width and brightness, if some lines are very slightly different widths or shades of red to the others you do not have 1:1 mapping

If there is a slight pattern to the lines that repeats every #th line then you do not have 1:1 mapping

View this sample image below on your computer monitor (*NOT* your TV) to see what 1:1 mapping looks like

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Another way to see what 1:1 mapping looks like is to view 1920x1080.gif in your image viewer, now zoom in + out slightly and look really closely at what the stripes do at different zoom levels.

 

Initial adjustments to try and get 0% overscan with 1:1 pixel mapping

1. Go into Video card settings
   AMD = Catalyst control centre, NVIDIA = nvidia control panel
   Check your display resolution is set to the native panel resolution (ie 1920x1080)
   Adjust overscan/underscan to 0%
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2. Run tigerdave.exe
3. Keep changing the display mode (16:9,4:3,14:9 Zoom,etc) on your tv, until you the arrows touch the edge of the screen.
   On a samsung tv this display mode is called "Just Scan" on a panasonic I think it is called "HD Size"
   Note: usually "16:9 mode" has overscan in it. Not all TVs can do 0% overscan

Help My TV can't do 0% overscan or 1:1 pixel mapping

1. Run tigerdave.exe (doesn't matter which one)
2. Set the tv's display mode that shows as much as possible of the tigerdave1080p test pattern (eg. 16:9 mode)
3. Go into video card settings and adjust the overscan/underscan slider.
   Give enough underscan so that you can see as much as possible WITHOUT any black border.
   It doesn't matter if some of the image is still cut off we will fine tune this in the next step.
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4. Run Mediaportal and go into settings -> GUI -> Screen -> Screen calibration.
5. Fine tune the display so the blue arrows touch the edge of the screen.

Note for other displays

• If you have an HD Ready display with a 1280x720 native pixel panel you should use 1280x720 as your desktop resolution and then use TigerDave.1280x720.exe to adjust for 1:1 mapping and overscan.
• You can only use TigerDave.1280x720.exe if your desktop resolution is 1280x720
• If your resolution is not 1280x720 you can set your desktop background to white, and move your mouse pointer into the top left corner of the screen and use that as a guide for adjusting overscan.
• You can also use "5-sharpness & overscan.mp4" inside "basic calibration.zip" in the next post. Play the video fullscreen then adjust overscan settings.
• If you have an HD Ready display that is not 1280x720, it's always best to try setting the desktop resolution to same as the native resolution of the panel. This doesn't always work with some panels. If you can't use the native panel resolution, the next resolution to try is 1280x720.
• If you have an old TV are forced to choose between 1080i and 720p desktop resolution, always pick 720p. Don't use interlaced desktop resolutions, they will not give you smooth playback.
• If you have an HD Ready TV and can't find your native display panel resolution then use 1280x720
• If you have a computer monitor, it does not suffer from non 1:1 mapping, overscan or underscan as long as the display resolution = native monitor resolution