I've got some pictures from a camera attached to a basic astro telescope, a Sky-Watcher Capricorn 70 (70mm input aperture, 900mm focal length).
I'll tag the images with F-Number 13 (~900/70), and FocalLength = 900mm.
Is there any convention for tagging LensModel in this case? I think that LensFun for example tries to interpret numbers in the LensModel string.
I guess the string would just be for my benefit, but are any of these "better"?
Sky-Watcher Capricorn 70/900 Telescope
or
Sky-Watcher Capricorn 70
or
Sky-Watcher Capricorn f/13 900mm
I would go with something like "Sky-Watcher Capricorn 900mm f/13".
- Phil
Thanks, that keeps all numbers in the format that software designed for camera lenses would expect, even if it isn't strictly the model name of the scope. I decided to put the word "refractor" on the end as an indication of the lens design. I expect in the future I'll have examples with "Newtonian reflector", and so on. I'll be able to search for LensModel contains "refractor", or whatever.
These are the arg files that I used for the tagging my images:
# Sky-Watcher Capricon-70 "70/900" (D=70mm, f=900mm, f/13) refractor telescope
# Quotes are not stripped from these values. Avoid spaces at the end of lines.
-LensMake=Sky-Watcher
-LensModel=Sky-Watcher Capricorn 900mm f/13 refractor
-LensInfo=900 mm f/13
-FNumber=13
-MaxApertureValue=13
-FocalLength=900 mm
And for images taken via a x2 Barlow
# Sky-Watcher Capricon-70 "70/900" (D=70mm, f=900mm, f/13) refractor telescope with a 2x Barlow lens.
# Quotes are not stripped from these values. Avoid spaces at the end of lines.
-LensMake=Sky-Watcher
# Converter x2 Barlow lens
-LensModel=Sky-Watcher Capricorn 900mm f/13 refractor + converter Sky-Watcher 2x Barlow
-LensInfo=1800 mm f/26
-FNumber=26
-MaxApertureValue=26
-FocalLength=1800 mm