>Does anyone have any comments or suggestions for a source of standards
>as well as on the whole issue of the relationship between intensities
>(WITHIN AN IMAGE).


I think there is no perfect answer here.  However there are a couple of
points to make.  First, is you are looking at the ration of intensities
in two comprtments you must subtract the actual measured background
first (I know this sounds obvious but people do forget).

Second, you need to be sure that neither fluorochrome is saturating -
going from (eg) the 3% ND to the 1% should reduce both signals to
one third.

Third, this provides a direct check on linearity of the detection system -
use a fluorochrome that won't saturate or bleach and check that increasing
the % of the laser power reaching the sample is increasing the signal
proportionately.

                                        Guy Cox

Dr. Guy Cox,   |                    ooOOOOOOoo
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