Colour Calibration

[Nifty Hat Mitch]

On Mon, Aug 02, 2004 at 11:41:55PM -0700, Michael A. Peters wrote:
> 
> Are there utilities for Linux for proper monitor calibration - such that
> image editing done in the gimp, when sent to a lab (like Adorama), will
> end up looking like what I expect?

What does Adorama tell you (you lab)?
Since color can be critical (and subjective) you need a closed
loop interaction and relationship with the lab/ print shop.

Mostly you need to calibrate the monitor.  This might be one of those
cases where it pays to dual boot (or use a second system + OS).  Dual
boot, if only to run the calibration tool recommended (certified) by
the lab and then to preview the final work in a different context.
Using a 'certified' tool can save your bacon when the printer screws
up.  Have a sign off process and check list paper trail.... ;-) if
big money is involved.

You may also need an external calibration device.

Pay attention to the source of your images, i.e.  your digital
cameras, scanners and printers (garbage in garbage out).

Many paint stores have inexpensive 'color' chips. You can build some
reference pages to photograph and scan.  This can give you some early
warning and control on your side.  Labs will sell you references too.

There are tools to adjust various parameters of the video card. See
the man page for xcms, xcmsdb, xgamma and xvidtune (caution with
xvidtune, RTFM).  xgamma may be the only one you need.  Some cards do
not let you adjust interesting things.

Some calibration tools expect you to place a 100% red image on the
screen, followed by 100% white, 100% black for all three component
colors.  I have seen people post such programs on this list that do
this, so check the archives.  The last one mumbled something about how
to turn off the cursor and full screen (no X decorations).

If you are not using million of colors (+24 bit) manage your personal
expectations (system setting --> display) to match.


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