> The spyder 3 produces values of exactly 0.0 all the time for black on my CRT. So even if there is a problem of erroneous readings of something close to zero, it would be indistinguishable from valid measurement... > The manufacturers driver produces the same reading. Could I ask you to try to measure very dark grey (I tried using XYZ: 0.196480 0.200497 0.384248) instead. Maybe you would be able to reproduce the problem. Please make at least 20 measurements before giving up :) Also, could you make the same test but with full white and about 20 measurements? Does the result decrease, increase or stays more or less the same? > Even with your modification (bumping the time up to 32 seconds), The whole measurement takes about 19.5 seconds (tested with spotread -yl). > [For comparison the i1pro produces XYZ values of 0.048 0.051 0.064, > and the Spyder 2 values of 0.035 0.042 0.043 ] So the error is 0.064 -> perfectly acceptable for me :) I was referring to errors of about 0.200 when measuring a value of about 0.200 :).