[RASMB] XL-I optics issue

[Stephen Eyles]

Hi helpful people,

Has anyone come across an issue where the bottom part of the scan of a  
cell looks wrong?  If I look at the fringe pattern I can see that the  
bottom of my sample is around 7.25 cm, but both interference and  
absorbance scans look strange beyond 7.15cm.  Is this a potential  
problem with something in the optics?  It seems to happen in all three  
of the cells I am running so I don't think it can be a dirty cell  
problem.  The sample concentration is about 10-20 uM and I'm getting  
fringe displacements of 1-2 fringes.
Any help and/or tips would be greatly appreciated.

Steve

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Dr Stephen J. Eyles
Director, Mass Spectrometry Facility
Senior Lecturer, Polymer Science & Engineering
University of Massachusetts - Amherst
A528 Conte Building
120 Governors Drive
Amherst, MA 01003, USA
eyles at polysci.umass.edu
Tel: (413) 577-1528
Fax: (413) 545-0082
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