[RASMB] counterbalance functions

[Walter Stafford]

Glen: It isn't the collimated light that is focused by these systems. It 
is the rays coming from the object  plane in the cell. And vertical 
movements do matter. Remember: the collimated rays end up at the focal 
point of the lens, diverge after that and do not make it to (i.e. 
converge at) the image plane. I can't say what the magnitude of the 
effect is but it is there.

Glen Ramsay wrote:
> the vertical movements probably don't affect the absorbance and 
> interference measurements too much as these beams are relatively well 
> columnated and insensitive to height.

-- 

===============================================
Walter F. Stafford, Ph.D.
Senior Scientist
Boston Biomedical Research Institute
64 Grove Street
Watertown, MA 02472
617-658-7808
skype: w.stafford3
----------------------
"Be kind, for everyone you meet is fighting a hard battle."  -Plato
------------------------------------