Determining the actual scale factor ...

[Hauke Heibel]

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
dataset.

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?

Regards,
Hauke

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