Datacolor User to User Support Group.

--- In colorvision_group@yahoogroups.com, "Kris" <km-yahoo@...> wrote:
> I'm curious if you're making multiple readings and averaging?

I'm taking single readings in this instance.  I have already done a
different personal study on the stability of the measurement device
itself.  I noticed that the device is extremely stable.  I used 150
seperate readings from the white tile taken aproximately 3 seconds
apart and came with a maximim delta-e of 0.5 and one standard
deviation of 0.02.

> It does seem that the 4-5 delta-e measurements are pretty surprising, 
> as well as the wide variation from patch to patch.

Yes .. I thought so also.  One question which occured to me was how
important is it to measure the complete spectrum returned by a sample
vs the several LED lights used in the 1005.  Technicaly if the LEDs
have a spectral distribution which mimics the bell shaped spectral
response curves to which our eyes cone receptors are sensitive ... it
shouldn't make a difference (clever though on the part of ColorVision).

On the other hand if some of the pigments in the ColorChecker chart do
not merely reflect spectral energy but in fact absorb and re-emit them
in different wavelengths (like optical brighteners do) then those 4-5
delta-e measurements would make a lot of sense.

Of course ... it may just be that the Mini ColorChecker isn't that
accurate either ;-)  I have made several profiles with my system and
they are of wonderful quality.  For its design goal the 1005 excedes
my expectations (if you're on the fence go get one ... you'll be happy).

If anyone would like to review my calculations or measurements they
are of course always welcome.  Please let me know and I will forward
you my spreadsheet with the calculations and all the readings.

Thanks for the responses!