Robert Hart
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Recently I remade the barrel of a Laowa rear anamorphic adaptor to accept Nikon F-Mount stills lenses which I have been using via a EF-Mount adaptor ring. Whilst I had the lathe set up for fabricating a tractor part and a suitable short piece of metal stock was available, I decided to remake an adaptor for an old Century Optics 16:9 anamorphic lens which was part of a Sony PD150 kit.
I had roughed up an adaptor from pieces of PVC water pipe fittings years ago. It was never much good and I had intended to remake the part in metal once I had established the form which worked. I never got around to it and made do with the plastic piece for the few times I wanted to use the adaptor. When in use I was hoping and praying the blue plumber's glue would not let go.
Cutting fine 0.7mm pitch filter threads is a bit of a nightmare with my meagre skillset and the cheap chinese lathe. It can be done but lots of workarounds are needed to get the precision. The thread cutting is the very last operation. It is the most likely to go wrong and ruin all the work which came beforehand, like about five hour's worth.
The Century Optics anamorphic for the Sony PD150 has an exit pupil which is smaller than the Letus, rare Panasonic, rarer Optex and the newer SLR Magic anamorphic adaptors people use. The fitment to the PD150 was via a bayonet attachment which held the removable lens hood.
Rather than cut out the reliefs for the bayonet lugs in the new adaptor, it is easier to slack off the stop screw in the attachment ring, take it all the way off, offer into the rear of the anamorphic lens the flange of the new adaptor then screw the ring back on behind it and cinch it firm.
If it was to be used often and rapid lens changes were desirable, then several adaptors could be made complete with the bayonet reliefs and remain attached to lenses. As it will be infrequently used for script teasers, I won't be making more. The Century anamorphic lens has an adjustment so where the adaptor ends up when screwed into different lenses does not matter.
For professional cinema lenses it is not an option. For smaller stills lenses like the Nikon F-Mount lenses with 52mm filter fronts and small diameter front elements, it works fine. The sharpness and clarity are adequate but I would not say outstanding. The anamorphic lens was originally purposed for standard definition television quality.
The F-Mount lenses known to work with it with the URSA Mini 4.6K EF are the Sigma 28mm f1.8 (requires step-up ring), genuine Nikon 35mm f1.4, genuine Nikon 50mm f1.4, genuine older and newer Nikon 85mm f1.8. The front anamorphic increases the field-of-view the sensor sees through the lenses and you get a few flares and ricegrain bokeh on pinpoint highlights.
The adaptor is the skinny gold-coloured piece of bronze between the anamorphic lens and the Nikon lens.
I had roughed up an adaptor from pieces of PVC water pipe fittings years ago. It was never much good and I had intended to remake the part in metal once I had established the form which worked. I never got around to it and made do with the plastic piece for the few times I wanted to use the adaptor. When in use I was hoping and praying the blue plumber's glue would not let go.
Cutting fine 0.7mm pitch filter threads is a bit of a nightmare with my meagre skillset and the cheap chinese lathe. It can be done but lots of workarounds are needed to get the precision. The thread cutting is the very last operation. It is the most likely to go wrong and ruin all the work which came beforehand, like about five hour's worth.
The Century Optics anamorphic for the Sony PD150 has an exit pupil which is smaller than the Letus, rare Panasonic, rarer Optex and the newer SLR Magic anamorphic adaptors people use. The fitment to the PD150 was via a bayonet attachment which held the removable lens hood.
Rather than cut out the reliefs for the bayonet lugs in the new adaptor, it is easier to slack off the stop screw in the attachment ring, take it all the way off, offer into the rear of the anamorphic lens the flange of the new adaptor then screw the ring back on behind it and cinch it firm.
If it was to be used often and rapid lens changes were desirable, then several adaptors could be made complete with the bayonet reliefs and remain attached to lenses. As it will be infrequently used for script teasers, I won't be making more. The Century anamorphic lens has an adjustment so where the adaptor ends up when screwed into different lenses does not matter.
For professional cinema lenses it is not an option. For smaller stills lenses like the Nikon F-Mount lenses with 52mm filter fronts and small diameter front elements, it works fine. The sharpness and clarity are adequate but I would not say outstanding. The anamorphic lens was originally purposed for standard definition television quality.
The F-Mount lenses known to work with it with the URSA Mini 4.6K EF are the Sigma 28mm f1.8 (requires step-up ring), genuine Nikon 35mm f1.4, genuine Nikon 50mm f1.4, genuine older and newer Nikon 85mm f1.8. The front anamorphic increases the field-of-view the sensor sees through the lenses and you get a few flares and ricegrain bokeh on pinpoint highlights.
The adaptor is the skinny gold-coloured piece of bronze between the anamorphic lens and the Nikon lens.
