Matching Samsung ledTV to Apple cinema display

Hornady
2013-11-06
2013-11-10
  • Hornady
    Hornady
    2013-11-06

    Hi Florian, thank you for wonderful dispcalgui!

    I'm trying to match a Samsung ledTV (55F6300) to my old Apple cinema display 23".
    I'm using Spyder4 (Express). The viewing room is dark.

    I want them both to match and aim for Rec709 2.2 from your dispcalgui.

    I used these settings for Apple display:
    Spyder4 mode: LCD Generic
    WhitePoint: 6500 Daylight
    Gamma: 2.2 Relative
    WhiteLevel & BlackLevel: as measured
    BlackPoint Compensation: yes
    Interactive display adjustment: yes
    ProfileType: XYZ lut + matrix
    CalibrationSpeed: low
    ProfileQuality: high
    TestChart: extended for lut profiles

    For the Samsung I used same settings, tried Spyder4 both mode LCD generic & WhiteLed.

    I cannot get matching colors. The Samsung always get somewhat reddish on dark skintones, and always warmer shadows compared to the Apple display.

    On the Samsung, I have turned off all their color enhancing features, as I've learnt from TV review websites, eg:
    DynamicContrast: off
    HDMI BlackLevel: normal
    ColorSpace: native
    FleshTone: 0
    ..

    I tried redoing calibration countless times fiddling with other settings for 4+ days, still the results are not satisfactory. Both of them just won't match. On a sidenote, I have successfully matched an LG IPS 237L to the Apple cinema display.

    Do you have any suggestion? Or is it the Spyder4 that is not good for LedTV?

    Regards,
    Hornady.

     

  • Anonymous
    2013-11-06

    Do they have the same "red"? (XYZ coords for example, easily measurable)
    It's very usual that a lot of TVs have their "red" a little to the left in "purple" segment of xyY. Just a tiny shift to the left.

     
    • Hornady
      Hornady
      2013-11-09

      Same red?
      Hi-red is same, hi-yellow is almost same - no problem there.
      Problem is on subtle sepia (low-sat) colors and dark low-sat colors, they look quite different. Example: pinkish grey on Apple appear greenish grey on Samsung.

       
  • Florian Hoech
    Florian Hoech
    2013-11-07

    Calibration alone can only affect white- and blackpoint, grayscale neutrality. Does the software you're using actually make use of the ICC profile? Only then color correction is possible.

     
    • Hornady
      Hornady
      2013-11-09

      I am using mac os x. Sorry, i mean i did both calibration & profiling.
      I did calibration & profile first on Apple display, then on the Samsung.

      Funny thing is, when in interactive calibration step checking the RGB gain for white point of 6500K, the Samsung TV is showing different white than my Apple display, even tho the RGB is balanced.

      So I think the Spyder4 somehow has different readings when on Samsung led and when on Apple LCD. Even tho I set both to calibrate on 6500K Daylight.

      How come is this possible?

      Assuming the Spyder4 has different response on ledtv & on LCD monitor, I also took a different approach to calibrate the Samsung:
      - set white point to 'As Measured' ref:Daylight, black point correction 100%.
      - on RGB interactive calibration step, i disregard the RGB bar readings and adjust the white patch visually to match another white patch opened on the Apple display.
      - then continue to calibration & profiling as usual.
      The result is better, but still a bit off. I think the Spyder4 is struggling to get correct readings on very dark patches, so black point is not same temperature to the measured white point, and the resulting dark gray gradient is a bit off compared to the Apple display.

      I'm very frustrated.

      How can I ensure the Spyder4 colorimeter to get correct & consistent readings on ledTV & on LCD?

      Many thanks.

       
      Last edit: Hornady 2013-11-09

  • Anonymous
    2013-11-09

    First of all, did you use some Calibration Spectral Samples (.ccss) prior to calibration?

    Does any of these displays have an "offset" (next to "gain") feature in OSD? This is useful to black point. Usually TVs do not have it.

    I think that it wold be easy to calibrate and profile Samsung TV first. Then read achieved white point from TV, "actual" one not D65. Last calibrate and profile your Apple Display to that white point.

     
    • Hornady
      Hornady
      2013-11-10

      I did import from spyder .exe installation.

      The Samsung TV has offset RGB settings also.

      Thanks for your suggestion to calibrate the Apple to match the Samsung. I also have thought about it, I will do it as last resort (maybe tomorrow).

       
  • Florian Hoech
    Florian Hoech
    2013-11-09

    Funny thing is, when in interactive calibration step checking the RGB gain for white point of 6500K, the Samsung TV is showing different white than my Apple display, even tho the RGB is balanced.

    So I think the Spyder4 somehow has different readings when on Samsung led and when on Apple LCD. Even tho I set both to calibrate on 6500K Daylight.

    How come is this possible?

    Like the poster above me said, for different panels and backlighting technologies, colorimeters usually need a correction (spectral or matrix based). So I guess for the Apple display, the measurement mode should be "LCD (CCFL)" and for the Samsung TV "LDC (White LED)". This could help improve the situation. Have you imported the colorimeter corrections from the Spyder software into dispcalGUI? Only then the additional measurement modes will be available (note, if you haven't installed the Spyder software, download the Windows installer even under Mac OS X for the purpose of importing the corrections).

    Assuming the Spyder4 has different response on ledtv & on LCD monitor, I also took a different approach to calibrate the Samsung:
    - set white point to 'As Measured' ref:Daylight, black point correction 100%.
    - on RGB interactive calibration step, i disregard the RGB bar readings and adjust the white patch visually to match another white patch opened on the Apple display.
    - then continue to calibration & profiling as usual.

    Yes, this is also what I would have recommended.

    I think the Spyder4 is struggling to get correct readings on very dark patches, so black point is not same temperature to the measured white point, and the resulting dark gray gradient is a bit off compared to the Apple display.

    Making both displays match in terms of apparent black level is probably tough. You could measure the black level on the Apple display and set that as target for the TV, but it will lighten up the black on the TV as I assume it has the deeper native black of the two.

     
    • Hornady
      Hornady
      2013-11-10

      Thanks for your suggestions.

      I am thinking another approach:
      - set the white point visually
      - set the black point visually (set as measured) --> sorry maybe this can't be done?
      - then do calibration as usual.

      1 question:
      Can I set a 'grey point' visually in dispcalgui? (Same as measured)
      If it can be done, then I think the problem is solved.

      I'm thinking of this approach because the Samsung ledTV has many color adjustment options, eg: 10p WB, gain, offset, also custom color space where we can adjust RGB & CMYK balance.

       
      Last edit: Hornady 2013-11-10