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Have I achieved 1:1 pixel mapping?

Discussion in 'Projectors, Screens & Video Processors' started by Crocodile JD, Oct 13, 2003.

  1. Crocodile JD

    Crocodile JD
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    Hi guys

    Need some help on this, I never really understood screen resolution issues.:blush:

    I've got a Sanyo PLV30 LCD PJ which has a native res. of 800x600 which is the SVGA standard I believe. Over the w/e I hooked it up to my PC which I set to output 800x600 on screen res with 32 bit true colour at 75kHz fequency. I then ran PowerDVD to playback DVD,s. I configured PowerDVD to playback both 4:3 and Widescreen material at 800x600 (32 bit 75kHz). I also selected the "Don't change aspect ratio" option as well

    The DVD's filled the same amount of screen as it does when I play back via my DVD player, and the image looked pretty good. But the question is have I optimised the PJ performance (i.e. achieved 1:1 pixel mapping) or not?:confused:

    Hope you can help:smashin:

    Cheers

    Croc
     
  2. Mr.D

    Mr.D
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    well you could contruct an image 800x600 of alternating black and white single pixels and see if it displays cleanly.

    You might also find the projector benefits from being fed 60Hz. Most digital panels refresh at this rate regardless of input so if you feed it 75Hz it may well be remapping the frames leading to softening.
     
  3. johnm60

    johnm60
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    If you want to be sure whether you have a 1:1 pixel mapping, use this guy's test pattern on your windows desktop. I have found it very useful in the past. Remeber to make sure you tile it and not stretch it.

    http://www.marky.com/main/index.html


    Cheers
    John
     
  4. Crocodile JD

    Crocodile JD
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    Thanks for the replies chaps. It is clearly a more complicated issue than simply setting your PC to SVGA then. I read the thread by Marky over on AV Sience and messing around with Phase etc sounds a little beyond me:(

    I don't even know how to construct the black/white 800x600 image? Am I a lost cause or is it all actually easier than it sounds?

    Cheers

    Croc
     
  5. cyberheater

    cyberheater
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    Basically, if the machines native resolution is 800x600 and you've set you PC to that resolution @ 60hz then you should have 1:1 pixel mapping.
    When windows has booted, does all the text look clear and sharp or does some of it appear smeared. If it all looks sharp then you've achieved 1:1 pixel mapping.
     
  6. Crocodile JD

    Crocodile JD
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    cyberheater

    I was hoping someone would say that. On boot up, all the text looks sharp, although I,ve been running it at 75 Hz, will change to 60.

    Cheers

    Croc
     
  7. Kramer

    Kramer
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    No need :eek:

    :)
     
  8. cyberheater

    cyberheater
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    Just copy and past this into a documents folder and then run it as a backdrop with tileing but NO stretching. If there are no flaws in the image then you've proved your 1:1 pixel mapping.

    [​IMG]
     
  9. Crocodile JD

    Crocodile JD
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    cheers guys, I'll give it a go

    Croc:smashin:
     
  10. buns

    buns
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    what does a flaw look like!?

    Ad
     
  11. theritz

    theritz
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    Ad,

    fuzzy bands in the image would be a no-no................. should be nice and clear......... btw, using keystone correction will **** up the effect - if you have to use keystone for install purposes, when setting up your !:!, turn off keystone - you can dial it in afterwards if you have to.......................


    Sean G.
     
  12. Clint C

    Clint C
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    theritz surely this image (or link to it) has got to go in the FAQ? I personally found it very useful.

    Clint
     
  13. theritz

    theritz
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    clintc,

    Yip, an appropriate link to Mark's pattern and instructions added to the FAQ...............


    Sean G.
     

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