Quote:
Originally Posted by 5ash
Estimating magnification of a captured image?
Years ago when I had one of the original G star cameras , we estimated the magnification as about that of a 6 mm eyepiece. Is there a formula to calculate the eyepiece equivalent magnification for a camera.
Regards philip
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Hi Phil,
The equivalence to me would be achieved when the view through the eyepiece has the same field of view as that from an uncropped image of the same scene. On that basis you could simply plug the various telescope/optical parameters you are simulating in to any of the several Field of View programs available and look to see for
what eyepiece focal length the FOV of both systems you are comparing is equal. Then hey presto you have your answer.
Here is an example of just such an
FoV Calculator. Select an object first, to see the resultant data.
Another one to help calculate
Imaging Sensor FoV with various focal length lenses/scopes. Not that intuitive at first
As for a direct formula approach, one could be worked out on the same basis as the above, with some underlying assumptions, but given the variables involved would be easier via the programs suggested.
As an aside and for what it's worth, I always like to remember that a focal length of 1031mm on a full frame optical system will give an ~2 degree horizontal FOV on a typical 3:2 format DSLR sensor. From there its possible to work out MANY sensor / scope combinations.
Best
JA