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Re: Calibration- pixels/um or um/pixel

Posted by Heeschen, Bill (WA) on Dec 17, 2010; 6:01pm
URL: http://imagej.273.s1.nabble.com/Calibration-pixels-um-or-um-pixel-tp3686165p3686166.html

Regarding pixel scale:
(I receive postings in digest mode, so this inquiry may have already
been answered)

If you "Show Info..." for an image in ImageJ (Image->Show Info...), both
ways of describing spatial calibration are listed.

Pragmatically, it is easier to measure the number of pixels across an
object of known size (hence pixels/micron) than it is to try to measure
the real-world width of one pixel (micron/pixel).

Onward,

Bill
William A. Heeschen, Ph.D.
Microscopy, Digital Imaging
The Dow Chemical Company
Midland, MI  48667
[hidden email]

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Date:    Thu, 16 Dec 2010 18:25:43 -0500
From:    David Knecht <[hidden email]>
Subject: Calibration- pixels/um or um/pixel

I was having trouble setting up calibrations in Micro-manager yesterday
and finally figured out why.   Set Scale in ImageJ reads out in
pixels/micron.  If you take those numbers and try to enter them into
Micro-manager's calibration, it asks for the data as um/pixel.  The
Micro-manager folks asked if it could be changed in ImageJ to conform to
their setup.  I don't know if there is any "standard" way of doing this,
but it would be nice if the two used the same units to avoid confusion.
However, I am sure that if it is changed in ImageJ, lots of people might
have their data altered.  Is there an easy way to resolve this?
Thanks- Dave

Dr. David Knecht    
Department of Molecular and Cell Biology
Co-head Flow Cytometry and Confocal Microscopy Facility
U-3125
91 N. Eagleville Rd.
University of Connecticut
Storrs, CT 06269
860-486-2200
860-486-4331 (fax)

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End of IMAGEJ Digest - 15 Dec 2010 to 16 Dec 2010 (#2010-163)
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