Adapter for M39x0.75mm Enlarger Lens on Sony E Body

thingiverse

This is a simple focusing adapter that I made for my Rodenstock Omegaron 150mm f/4.5 enlarger lens to be used with my Sony E-mount cameras. This particular enlarger lens has a 39mm diameter thread with 0.75mm pitch -- beware that many enlarger lenses have different threads (including 39mm with 1mm pitch). The tube length is intended to work with lenses from about 135mm to 180mm with a good focusing range, although focusing is slow because the focus thread has just a 3mm pitch. The Sony E mount on this part is designed for the later all-metal E-mounts, and it is a loose fit on most E-mount bodies -- I might revise this, but it is usable as is. The last three photos were taken using this lens and focusing adapter on a Sony A7. Note that there is very slight vignetting, which is due to the width of the opening in the adapter; it is not yet clear if the vignetting can be avoided by using a wider tube design.