Determining the actual scale factor ...

Hauke Heibel hauke.heibel at
Thu Dec 2 09:29:47 EST 2010

After looking at the CMU-1 dataset I am wondering how reliable the
OBJECTIVE_MAGNIFICATION values are. At level 0 the dataset has a pixel
spacing of ~0.23 microns and according to a whole bunch of references
from the web this is typically corresponding to a 40x objective
whereas the objective magnification is stored as 20x in the CMU-1

So, either the assumption that 0.23 microns always correspond to 40x
objectives is wrong or the file entry is not reliable. Maybe somebody
can confirm or disprove the first assumption?


p.s. I started a feature branch for the objective power implementation
on my github fork.

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