[RASMB] question for XLA experts

[Peter Schuck]

Borries, 
with the absorption system I'd suggest looking at the intensity data.
There you would see directly (and for reference and sample channels
separately) where the shadow starts and ends, and I would take the 50%
transmission values as a reference.  My feeling is that the interference
optics may be more precise, though.  
Peter

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Peter Schuck, PhD
Molecular Interactions Resource
Division of Bioengineering and Physical Science, ORS
National Institutes of Health
Bldg. 13 Rm. 3N17
13 South Drive 
Bethesda, MD 20892 - 5766
Tel: (301) 435-1950
Fax: (301) 480-1242
email: Peter_Schuck at nih.gov
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