Determining the actual scale factor ...

[Hauke Heibel]

Hi,

I am wondering whether you know if there is a way to determine the
actual scale at which an image was taken. It is not uncommon in
microscopy applications to offer 1x 2x 5x ... 40x zoom settings
corresponding the standard magnification lenses. In the MIRAX format
there is a tag called OBJECTIVE_MAGNIFICATION which seems to state the
zooming factor at which the zero-th pyramid level was acquired. This
is quite nice since it would allow users to implement exactly the
aforementioned functionality.

I browsed a bit through the TIFF specs but did not find anything
corresponding which were jumping right to my eyes. I am just asking
since it makes very little sense for me to implement such a function
for MIRAX only when there is no way to achieve the same with other
image formats.

So, in case anybody has an idea and is willing to share it, I would be
happy to hear about it.

Regards,
Hauke