05-25-2013, 07:04 PM
I got this Epis 400mm 1:4 projector lens. A search learned that it actually is a Leica made/designed lens.
It is about 13cm wide, with a ~10cm front element diameter. Apparently (looks like it too) it has 3 elements. The whole lens assembly 11.5cm long, and it has an outer "tube" with focussing guidance.
The lens has a very wide projection image. If I assume a crop factor of 2.4 for FF in comparison to 6 x 9, this lens would make a fine longer portrait lens on MF 6 x 9 format (166m, f1.66 FF equivalent).
It would also do fine as a large format lens, or tilt shift lens on MF (due to its huge projection circle).
I have not experimented enough with it to know exactly how far it should be from the image plane at infinity, but quickly checking the front end would be about 48cm away from the image plane. If I want to mount it on my DSLR, that will mean I have to make a construction of about 40cm between lens and camera.
No idea yet what kind of resolution that would give... these long focal length lenses were for a long time preferred over tele designs because of central sharpness and contrast, and it is a Leica designed optic, so who knows?
I'll have to see what kind of construction(-materials) I can come up with. A shame my 6 x 9 camera is a fixed lens folder, else that would be a very interesting project :lol:
It is about 13cm wide, with a ~10cm front element diameter. Apparently (looks like it too) it has 3 elements. The whole lens assembly 11.5cm long, and it has an outer "tube" with focussing guidance.
The lens has a very wide projection image. If I assume a crop factor of 2.4 for FF in comparison to 6 x 9, this lens would make a fine longer portrait lens on MF 6 x 9 format (166m, f1.66 FF equivalent).
It would also do fine as a large format lens, or tilt shift lens on MF (due to its huge projection circle).
I have not experimented enough with it to know exactly how far it should be from the image plane at infinity, but quickly checking the front end would be about 48cm away from the image plane. If I want to mount it on my DSLR, that will mean I have to make a construction of about 40cm between lens and camera.
No idea yet what kind of resolution that would give... these long focal length lenses were for a long time preferred over tele designs because of central sharpness and contrast, and it is a Leica designed optic, so who knows?
I'll have to see what kind of construction(-materials) I can come up with. A shame my 6 x 9 camera is a fixed lens folder, else that would be a very interesting project :lol: