Lothman
•
Senior Member
•
Posts: 1,145
Super Macro - reverted Lens
Jun 3, 2003
Hi together,
similar threads like this some days ago:
http://forums.dpreview.com/forums/read.asp?forum=1012&message=5225555
inspired me using a reverted lens for macro shots. Therefore you need a lens with a great diameter to avoid vignetting. But the 50mm SLR lenses with an aperture of 1,2 to 1,4 are rather expencive (even on ebay).
Thus I tried an old slide projector lens - a Leitz Hector F=100mm 1:2,5. You can get that type of lenses rather cheap on ebay, might be you have to buy a whole slide pojector
For a proper adapting to the tubus I had to machine the lens housing on a lathe. Therfore I disassembled the lens. (I must have similar genetics than jkirk, we allways hear voices calling "open me") .
So 4 lenses in 3 Groups:

I shortened the housing at both ends and machined the right end to fit in an empty filter. I glued the empty filter with silicone. To avoid vignetting as far as possible you should get the lens as close as possible to the lens of the camera.

This type of lens has IMO several advantages over the SLR-Lens solution.
great lens diameter
cheaper
no moving parts like apertur and focus ring
should be designed for fix/open aperture and reversed use
but usually no filter thread therefore harder to adapt
and a larger working distance (about 72 mm in my case), which gives you the chance for good illumination.

at full zoom I get an imagewidth of 16,5 mm:

vignetting occurs 4 clicks to wide angle (3 clicks shows no vignetting). You can also see an increase in DOF, the post-it paper stack is sharp.

And to give you an idea for the DOF a pic of 2 matches at full zoom. The lower one I split in half to get a second layer for proofing DOF (about 1,5 mm). The pic was taken at f=11, the grid on the paper is 5 mm.

I hope this useful for some of you. I learned so much here in the fuji forum and with this contribution I want to thank all of you.
Best Regards
Lothman