Thanks, Henry! That sounds pretty good. The ED/APO connection is made in my mind now.
Certainly works great at f/8. Am I going to have spherical aberration issues, though?
I can tolerate some compared to an f/12....
That is to say, I don't have to go to 120x or even over 100x. My job is ball-parked now.
One thing I learned with my 'tin-man' setup is that 70-85x works really well for the eagles.
As they move I pick up more details about the coloration. They bank and dive when they are tacking.
If I could make 80x and sharp (chromatic and spherical), I'd be pretty happy.
Add brighter due to 80mm and due to better glass, and it looks like f/8-ED-APO is a good play.
Note that I'm not going for 'crystal clear'. Even on a good day, 500-1000m has its way with things.
I can ask for power...I can't ask for weather.
Certainly works great at f/8. Am I going to have spherical aberration issues, though?
I can tolerate some compared to an f/12....
That is to say, I don't have to go to 120x or even over 100x. My job is ball-parked now.
One thing I learned with my 'tin-man' setup is that 70-85x works really well for the eagles.
As they move I pick up more details about the coloration. They bank and dive when they are tacking.
If I could make 80x and sharp (chromatic and spherical), I'd be pretty happy.
Add brighter due to 80mm and due to better glass, and it looks like f/8-ED-APO is a good play.
Note that I'm not going for 'crystal clear'. Even on a good day, 500-1000m has its way with things.
I can ask for power...I can't ask for weather.
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