Digital BW, The Print

Well Andre,

This begs the question of you...

Did you, or if you did, were you successful in setting the temperature
and brightness, etc using your display's settings controls?  Did you
get some software feedback or simply click on the available preset
temperature etc in the Samsung?

We have a lot of displays in our classroom and some have pre-sets
which are wicked off from what the pre-set infers. Did you actually
tweak the color and brightness, ?? Or do you have a vLUT which
maaaaaaay be interfering?

I guess David is pointing out that you have a responsibility to set
all these settings in order for the calibration software to do what it
is supposed to do to be less evasive and that is part of their
instruction set now.

What do you think?

Jon



--- In DigitalBlackandWhiteThePrint@yahoogroups.com, cdtobie
<CDTobie@...> wrote:
>
> 
> On Jan 4, 2009, at 11:24:48 AM, "Jon Cone" <jon@...> wrote:
> 
> This parallels a discussion in progress on the Piezography list. What
> you did when calibrating your two LCDs was not to calibrate your two
> LCDs but to calibrate the video board of your computer because that is
> what EyeOne and CV Spyder, etc do.
> ___
> Hi Jon,
> 
> Well, its one part of what they do... They start by doing any possible 
> hardware calibration at the display, then move on the VLUT 
> adjustments, and of course create a profile defining the result when 
> they are done.
> 
> 
> Your video board when it is not
> calibrated has the ability to output 256red x 256green x 256 blue
> output levels to produce 16.7 million colors.
> ___
> Raw color, maximum number of values, but uncorrected... like printing 
> without color management...
> 
> In order to render
> grayscale without banding you need all those levels...
> ___
> In order to get nice smooth grays on screen, you should certainly 
> minimize the adjustments you make at the videocard level... none of 
> this effects the print, only the screen view, but its nice to not have 
> excessive banding on screen, as it interferes with seeing your 
> image...
> 
> 
> What calibration does is to reduce the output levels of the video
> board in order to realize the targets of color temperature,
> brightness, etc...
> ___
> No, first it does any adjustment that is possible at the hardware 
> controls level, which is certainly how "brightness" is adjusted in 
> virtually all cases. Color temp adjustment, for displays have RGB 
> Gains controls, are also done at the display hardware control level. 
> If Gains are not available, and you do not choose Native as your 
> whitepoint, and you do not have a display with LUT capabilities in the 
> display, then yes, the final choice is that the VLUTs in the videocard 
> are adjusted for this, as is gray balance.
> and saves this as a vLUT which loads when you
> startup your computer. Think of the vLUT as three curves being applied
> to your video board...
> 
> Calibrator displays like the Eizo CG series have an on-board hardware
> engine that produces billions of colors.
> ___
> Which is why users are instructed to set the Whitepoint and Gamma at 
> the display LUT level on such high end graphics displays first, in 
> advance of running third party display calibration software; or to use 
> software that does both. This could mean running a display 
> manufacturer's software once, to generally define gamma and 
> whitepoint, then running a third party product such as Spyder3Elite 
> every few weeks, on the high end graphics display and your other 
> displays as well (the specialty software for such displays does not 
> typically play well with other displays or calibrated multiple display 
> setups). Or it might mean simply running the manufacturer's display 
> software once in a while, if your needs are simpler. Or it might mean 
> using a specialty product such as ColorEyes to control the internal 
> LUTs on the display, as well as doing your general profiling of all 
> displays.
> 
> 
> The order of priority that calibration products use is: set display 
> hardware controls to optimal adjustments first (where available), set 
> display LUTs to any further corrections next, (if available), set 
> videocard LUTs to any remaining needed corrections, and finally, 
> define the end result in an ICC profile. Displays not having hardware 
> controls or internal LUTs should be targeted to Whitepoint and Gamma 
> values reasonably close to their native values, to avoid visible 
> banding caused by moving them too far with videocard VLUT corrections. 
> Those with such controls can afford to be adjusted somewhat somewhat 
> more widely. The new Apple 24 inch LED Cinema Display, for instance, 
> has neither hardware controls (beyond backlight control for 
> brightness) nor internal LUTs; but since its native gamma and 
> whitepoint are close to desired values, it calibrates nicely without 
> them, and at a price below displays with internal LUTs.
> 
> Once videocards and OSes have a functioning high bit pathway from the 
> card to the display, this will all become moot, and the desirable 
> features of internal LUTs will be equally functional at the videocard 
> LUTs, ending the whole problem of proprietary access to internal LUTs 
> and the communication issues that ensue, and eliminating most needs 
> for displays with internal LUTs.
> 
> Please feel free to repost to your other list...
> --
> C. David Tobie
> WW Product Technology Manager
> Digital Imaging & Home Theater
> Datacolor
> CDTobie@...
> www.datacolor.com/spyder3
> 
> 
> [Non-text portions of this message have been removed]
>