A few questions about Barlows.
What does a 2x barlow spec mean with respect to its focal length?
In your example above, the barlow is not in contact with the EP. Once you fix the barlow is there a unique position to focus the EP?
Assume for example, I would like the fp to be 12" outside the tube and I could buy a negative lens with a fl of 12".
Would that do it?
Is there a lens program that you could recommend?
Thanks,
Stu
What does a 2x barlow spec mean with respect to its focal length?
In your example above, the barlow is not in contact with the EP. Once you fix the barlow is there a unique position to focus the EP?
Assume for example, I would like the fp to be 12" outside the tube and I could buy a negative lens with a fl of 12".
Would that do it?
Is there a lens program that you could recommend?
Thanks,
Stu
