Found my problem. I had assumed that Show Info window displayed fixed values reflecting contents of the image file header. Setting the pixel size alters the Resolution in the Image Info window, reflecting the active image, not the metadata from the file. I wasn't always setting the mag. when testing whether the macro was correctly discriminating between a scanned image and an image from the digital TEM camera. That made the resolution change seem random.
I can work around this, now that I understand it.
Regards,
Glen
On Apr 1, 2011, at 4:53 PM, Glen MacDonald wrote:
> Is it possible for the 'getMetadata("Info") or 'getImageInfo()' macro commands to alter image properties?
> TEM negatives were scanned on an Epson scanner and saved in Adobe Photoshop CS3. The scans open in ImageJ
> with correct scan resolution, 600 or 1200 dpi, displayed in the Image Info window. But, after reading strings from metadata on several open images, the dpi will change from "Resolution: 600 pixels per inch" to something like "231.50 pixels per microns" or "399.99 pixels per microns". And only in a single image, not all of the open images.
>
> I'm not writing anything, only reading. Is there anyway to keep this from happening?
> Thanks,
> Glen
>
> Glen MacDonald
> Core for Communication Research
> Virginia Merrill Bloedel Hearing Research Center
> Box 357923
> University of Washington
> Seattle, WA 98195-7923 USA
> (206) 616-4156
>
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