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Author Topic: Aperture Value, not F-stop in Show Info... for photos  (Read 3019 times)

David Cockey

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Aperture Value, not F-stop in Show Info... for photos
« on: February 18, 2014, 06:33:07 AM »
The number in the Aperture line of the Show Info for photos is the Aperture Value, not the F-stop number, even though the number is preceded by "F/" which implies it is the F-stop number. A photo taken at F/8 is has an Aperture of F/6 shown, and a photo taken at F/11 has an Aperture of F/7 shown. This is not a major problem but it is confusing when looking in PhotoScan to see what F-stop was used for a photo.

"Aperture Value" = log("F-stop") / log(sqrt2)
"F-stop = (sqrt 2) ^ "Aperture Value"

My understanding (perhaps incorrect) is the raw EXIF data contains the Aperture Value rather than F-stop. Most software converts it to the corresponding F-stop value before reporting.
   

Alexey Pasumansky

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Re: Aperture Value, not F-stop in Show Info... for photos
« Reply #1 on: March 09, 2014, 02:19:10 AM »
Hello David,
 
Thank you for your remark, we have corrected Photo Info tab in the new release (build 1832).
Best regards,
Alexey Pasumansky,
Agisoft LLC