1. Join Now

    AVForums.com uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Picture Artifacts from iScan HD?

Discussion in 'Projectors, Screens & Video Processors' started by DDRUK_Lawrence, Jun 4, 2004.

  1. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    Hi All,

    I have an iScan HD hooked up to a PWD6. Sky currently goes through a RGB2YUV converter (but will eventually go direct into the iScan when I get the leads delivered that were delayed on my original order).

    Sky set to letterbox (I boost sky to other 4:3 TV's). iScan settings are letterbox input : 16:9 output using format 852x480 via analogue. The screens been set up for 1:1. To get this I had to fiddle with the h-size, v-size and clock phase on the panny. Overscan set to 4 and other little adjustments to centre the screen.

    Anyway, that's the background ;) When watching sky I notice that on some frames where an object is moving little black horizontal lines appear in the moving part of the picture. It doesn't happen all the time, it just must be certain scenes this is noticeable on. The best example I can give is a recorded program from sky+, when fast forwarding you get the on screen image in the bottom left that's a circle with green blocks and they rotate round. Occasionally (depending on the scene shown) the green blocks have these black horizontal lines in them. Pausing the picture makes them dissapear so it's only movement causing it.

    Anyone know why I'm getting this? Is there any way to minimise / stop it or is it just something I'll have to get used to? I thought it may be frame rate issues. I was seeing this effect on 50hz locked to 50hz. I have since unlocked 50 to 60 (which improves the flicker) but I still have the occasional little black horizontal lines effect.

    I haven't watched that many DVD's yet and I haven't noticed it happening when watching from the DVD.

    I upgraded the iScan HD's firmware yesterday (and had to set up all the settings again after it all defaulted grrr.) but it's still there.
     
  2. Dale Adams

    Dale Adams
    Active Member

    Joined:
    Jul 9, 2003
    Messages:
    175
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    18
    Ratings:
    +15
    It sounds like you're seeing deinterlacing artifacts when the 504 deinterlacer chip in the iScan mistakenly thinks the video signal is 2:2 pulldown. This is not unusual when you're feeding it an odd signal like fast forward or reverse play. It typically doesn't happen as much during normal play, but can occur under some circumstances.

    There is a setting in the iScan's Input Adjust menu which allows you to turn off 2:2 PD detection. This is the Film Mode setting and should be set to "Off". This will fix the problem, but will make any video source that does use 2:2 pulldown (i.e., pretty much anything originally recorded on film) look worse. If there are a few particular programs where the problem occurs, you might try using this setting on those first to see if you're happy with the iScan's performance on this setting.

    - Dale Adams
     
  3. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    Thanks Dale, I'll try setting the film mode to Off when viewing Sky+ and see if the problem goes away.
     
  4. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Law,

    I haven't seen this particular issue, but I have seen the odd stuttering effect and asked Dale about it a while ago. I got hold of the new firmware quite early in order to try 'film mode' and it fixed any issues for me...hopefully the same setting will fix your issue.

    Are you looking at the Scart=>RGBs adapter then?

    Also, after some prompting on here that 720p was better over analogue and 1:1 mapping was better over DVI, I have also tried sending 720p to the screen as opposed to 852x480. Amazingly enough, I think this has acutally improved the picture even though the screen is downscaling slightly. Give it a go and LMK what you think?? (the default 720p settings have width as about 1280 or so, so you will need to manually configure the horiz settings to 852 using the advanced user settings, and some of the others to centre the screen). You should be able to get the vertical lines test pattern correct, but the other two shoud look slighly stretched. If you get stuck, give me a shout and I will post my settings...

    JJ
     
  5. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    P.S. You shouldn't necessarily need Clock Phase to achieve 1:1 mapping - I know the picture kind of seems clearer for the checkboard when changing clock phase but this wasn't necessary for old firmware releases so I assume it is an iScan thing...

    Try also setting Clock phase back to the default value and see if the lines go away...

    JJ
     
  6. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    hi jason

    been using 720p for a while but have not adjusted any size of anything, if i change the size to 852 from 1280 like you say above i get 2 inch black backs down each side,

    any help would be great,

    did not know i needed to change anything :rolleyes: :rolleyes:
     
  7. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    hi jmack,

    Not sure if this is just a Panny thing (don't forget I also have a SD screen), but setting the default 720P assumes you have a high res display and hence my picture looks massively horiz stretched as if the panel isn't scaling horizontaly...even the panel horiz and vertical size settings cannot correct it at their min/max levels - not sure why this is the case but the following settings seem to work for me...(I still needed to use my screen horiz and vertical picture size settings a little)

    My settings are:

    Format
    =====

    H-shift =104
    H-size=852
    H-Front=254
    H-Sync=80
    H-Back=104

    V-### settings are unchanged from the 720p settings

    Sync
    ====

    H+V

    Colour space
    =========

    RGB

    I dont remember having to do this "resizing" when I tried 720p when I first got the iScan, but I have upgraded the firmware since then, maybe it's a weird Panny thing or an iScan bug???

    Hope this helps...:smashin:

    JJ
     
  8. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    i end end up with a picture smaller the 4.3 aspect with those settings.

    another thing i can change the contrast on the HD from under -20 odd to + 20 odd with no visable differance to me.

    cheers anyway, i`m starting to think mine might be a duff one. :(
     
  9. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Just edited above, please check ;)
     
  10. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    cheers , maybe mine is scalling it down for me, maybe the older model 4 series is different,

    did you see my ? on the contrast?

    i very happy with 720p as it is anyway, maybe i should stop messing :smashin:
     
  11. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Oh well...worth a shot! :)

    P.S. Like the new screenshot in your setup photos ;)

    JJ
     
  12. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    if i ever get screen burn from a logo it will say fashion tv, its like soft porn in the day time :devil: :devil: :devil:
     
  13. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Try changing ot with Avia or DVE...I think the HD contrast changes are only very slight as you are meant to use your display settings and calibrate those to the HD test patterns
     
  14. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    i have left everything on 0 on the plasma and iscan, seems about right on my setup.
    my dvd goes straight to plasma.
     
  15. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    After setting film mode to "off" for Sky+ the lines have disappeared :)

    Jasonjo, yes I'll be getting the Scart=>RGBs rather than using the Scart=>Component converter. I'll try out your 720p settings and see how it goes.

    The checkerboard test pattern with clock phase set to "0" had a lot of horizontal lines that jumped about up and down the screen looking like some kind of interference. I was able to almost completely remove them with the clock phase setting so I assumed this would be the optimal 1:1 result.
     
  16. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Good news Lawrence...

    Now I have lived with it for a few days, 720p is definitely better - even the wife said "have you changed something on your box, as the picture looks better" the other day...high praise indeed!! :D

    I would agree with your findings on the clock phase, but I am still not sure whether it is better to alter it or not??? Now that I am running 720p, it doesn't matter anyhow ;)

    JJ
     
  17. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    I have also changed to 720p but to me it looks pretty much the same. I'd like to say 720p is better but after you spend 30minutes or so fiddling about it may just be me thinking it so I can say it wasn't a waste of time ;) Anyway, the settings that were posted previously for 720p weren't right for me bacause it introduced black bars on the sides like a 4:3 image. Here's my fiddle session with constant complaints from the other half "oh your not fiddling again are you?" LOL

    Sky+ input (Sky set to letterbox format)
    DVDO:
    Aspect Ratio - Letterbox
    Input Adjust
    Pan
    Hor. -4
    Ver. -4
    Overscan 5
    Film Mode off
    AV Lipsync 3/4/5 (varies with Sky, damn cowboys)
    Output Setup
    Format
    720p
    H-Shift - 216
    H-Size - 1280
    H-Front - 70
    H-Sync - 80
    H-Back - 216
    H-Total - 1646
    V-Shift - 5
    V-Size - 720
    V-Front - 5
    V-Sync - 5
    V-Back - 20
    V-Total - 750
    Aspect Ratio 16:9
    Sync Type H+v
    Color Space RGB
    Framerate
    50Hz - Unlock 60 (I find this reduces flicker and the juder test still smooth)
    60Hz - 60 Locked


    Set the H-Size, H-Pos, V-Size and V-Pos on the Panny using the 1st iScan test pattern, clock phase returned to Zero.
     
  18. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Law,

    Why do you set output to letterbox and not 16:9?

    Strange how we have to have differnent settings when we both have exactly the same screen - are you at the latest firmware (1.08)?? Maybe it is due to the aspect thing above??

    JJ

    P.S. I get the same "oh no not that again..." whenever she see the iScan on screen menu :D
     
  19. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    Hi Jasonjo,

    Yes I have the latest firmware on the iScan. I set up Sky+ to output letterbox becuase firstly I boost the RF output around the house to watch Sky in the bedroom, kitchen etc. which are all 4:3 TVs. If Sky is set to 16:9 then all the 4:3 TVs get a vertically stretched image which looks nasty. The 4:3 TVs do have a format switch to 16:9 but this method isn't particulary "wife friendly". Secondly it still amazes me just how much 4:3 format pictures are still broadcast. I'd rather not have 4:3 squished to 16:9 and I can't stand a 4:3 picture on a widescreen so I prefer to see 4:3 zoomed to 16:9. With letterbox mode set on Sky the zoom on 4:3 pictures happens automatically although I have given the other half instructions on how to see a full 4:3 picture on the Panny by pressing the 4:3 aspect input button on the iScan remote if she is insisting she wants to see the text messages coming in at the bottom of the screen when watching Big Brother Little Brother! Pensonnaly I can live with chopping the top and bottom off from 4:3 broadcasts. Everything should damn well be 16:9 these days anyway! ;)
     
  20. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    i thought the lip sync adjusted it self to the source.

    will post my settings later will be intresting to see what we all prefer.
     
  21. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    The lip sync adjusts to the amount of processing the iScan is doing for the source but it can't account for the fact that sky tends to feed a signal that's already got lip sync issues.

    I'll be interested to see your settings jmack and how they compare.
     
  22. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    Mee too, I think jmack has similar settings to you though - it is only me that had to config horiz to 852 to get a non stretched picture. It is as if my Panny isn't scaling horiz...maybe it has got confused with the numerous picture memories after playing with nearly every iscan ouput format :)

    I can confirm the screen isn't scaling horiz with 852 as the vertical test pattens is 1:1 mapped even though the horizontal one isnt...

    Anyhow, picture is top so I think I will stop playing... :D :smashin:

    JJ
     
  23. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    plasma settings

    vga input
    picture mode normal
    brightness 0
    contrast 0
    white balance normal
    gamma 2.0


    brightness 0
    contrast 0
    saturation 0
    cue on
    y/c delay 0
    sharpness on



    Sky+ input 16.9
    DVDO:
    Aspect Ratio - 16.9
    Input Adjust
    Pan
    Hor. -0
    Ver. -0
    Overscan 0
    Film Mode off
    AV Lipsync auto
    Output Setup
    Format
    720p
    H-Shift - 220
    H-Size - 1280
    H-Front - 70
    H-Sync - 80
    H-Back - 220
    H-Total - 1650
    V-Shift - 5
    V-Size - 720
    V-Front - 5
    V-Sync - 5
    V-Back - 20
    V-Total - 750
    Aspect Ratio 16:9
    Sync Type H+v
    Color Space RGB
    Framerate
    50Hz - locked to 50hz the judder on 60hz does my head in.
    48Hz - 60 Locked(dont use any ntsc but i read somewhere about 48hz is good)

    my plasma is 2 years old this month and this is the best the picture has been :D :D
     
  24. DDRUK_Lawrence

    DDRUK_Lawrence
    Standard Member

    Joined:
    Apr 29, 2004
    Messages:
    34
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    6
    Ratings:
    +0
    jmack, almost identical to mine except I have to set overscan to fill the screen. I set the Panny's Hor. / Ver. Shift / Size to get the 1st iScan test pattern to fit the screen, I assume if you are filling the screen without overscan your Panny's Hor. / Ver. Shift / Size will be set to greater values than mine. I really hate the way that aspect of the Panny's set up doesn't have a numeric representaion for each setting!

    Is your Sky picture completely centered? You can tell this by measuring either side of the program gide OSG (shown by changing channel or hitting select) for the left and right and by measuring the horizontal bars on a 2:35 movie for the top and bottom. This is why I had to adjust Hor. -4 and Ver. -4
     
  25. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    I have to use an overscan of 5 to get the pciture right with NTL.

    I use an overscan of 3 with DVD.
     
  26. jmack

    jmack
    Guest

    Products Owned:
    0
    Products Wanted:
    0
    Ratings:
    +0
    mine is bang on centered.using that method, i do get a little black line down the right hand side on mtv hits . but everything else is fine.
     
  27. kevshed

    kevshed
    Member

    Joined:
    Oct 30, 2002
    Messages:
    1,156
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    48
    Location:
    bournemouth
    Ratings:
    +74
    just am observation..... I am currently using an RGB->Component converter to feed my iscan HD.... is RBGs converstion going to be better? Curious as its mentioned here.... thx (used for SKY+)
     
  28. Jasonjo

    Jasonjo
    Well-known Member

    Joined:
    Dec 3, 2001
    Messages:
    2,649
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    86
    Location:
    UK
    Ratings:
    +112
    I wouldn't necessarily say better, but I would think so. It is just a easier, cheaper and cleaner way of connecting.

    The keene adapter is only £5.99 (keene product code KA150S) - thereby allowing you to sell the RGB2YUV and avoid another converter in the loop as the keene adapter is purely passive...

    JJ
     
  29. kevshed

    kevshed
    Member

    Joined:
    Oct 30, 2002
    Messages:
    1,156
    Products Owned:
    0
    Products Wanted:
    0
    Trophy Points:
    48
    Location:
    bournemouth
    Ratings:
    +74
    OK, i'll give it a go.... Thx
     
  30. zAndy1

    zAndy1
    Distinguished Member

    Joined:
    Nov 26, 2002
    Messages:
    19,618
    Products Owned:
    2
    Products Wanted:
    5
    Trophy Points:
    163
    Ratings:
    +6,719
    Is there a specific cable required to connect the keene adaptor to the Iscan HD or will a component cable and any other phono cable do?

    Cheers,
    Andy
     

Share This Page

Loading...