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Rathenower Rectimascop 48 for Rectilux

Ever since having ordered the Rectilux I thought about fitting the Rathenower Rectimascop.

John Borlow has also created some Rehousing Sabots, which are now on preorder. I am happy to help out putting everything together, in case you need assistance.

Rectimascop 48/2x and RectiluxThis shows a Rathenower Rectimascop 48/2x Anamorphic inside Rectilux

It took some time, measurements, tests and patience to bring this together. Now I want to present a DIY Kit as the first step towards a possibility to get an amazing sharp scope fitted into the Rectilux.


The goals were:

  • least destructive
  • lightweight
  • rigid
  • infinity only
  • fast & easy adjustable
  • flexible - for the creative people
  • inside rectilux, behaving like a Kowa B&H
  • cool looking footage

Basically I disassembled the front and back elements. By using a lathe, I machined the front part down and added a thread, exact dimensions like it is found on the front of the Kowa B&H. After this, the Kowa front coupling fits. Connection done! The next Version will get a Cinelux front fit as it will be more flexible in terms of distance to the first lens.

The Prototype Rathenower Rectilmascope front element.

At he back of the front Element, I added 62-67mm Step up and 67-62mm Step Down Rings to reach the right length. Happy ending is a 62-58mm step down ring where the back end of the scope screws in. The alignment and perfect infinity distance can now be dialed in by screwing in/out the back element. Just use another 62-58mm step down ring as counter lock at the right position.

Why use Step Rings?

      • quick protoyping
      • cheap
      • fit Filters inside scope!

It fits the Rectilux as a hand the inside of a motorman's glove!


The following shots are with a working rehouse for the Rectimascop which fits in lenth, but not anodyzed. Due to that there are internal reflections. Due to this, the Images are very flarry & low contrast.

The steps are:

  • get the right tools.
  • Rectimascop disassembly (this is the greasy part...)
  • machine a custom front coupling + holes & threads & grub screws
  • Rectimascop Front machining & degreasing / cleaning
  • machine the rehouse
  • anodyzing
  • clean
  • assemble & adjust

Unthreaded Rehouse

Front Coupling and Front Element

A handheld shot with the final product at 200mm f5.6 on GH4

200mm + Rectimascop 48 rehousedshot handheld with the final product on GH4

Video Samples (shot with the Prototype)

Swiss Taxi Night Ride --- TeaserThis began as a test for cam, optics and car rig.

I am searching: Story(board) + Actors + small Team to pull the shooting off - as a short movie. There will be more Cam positions than just this. Like a Taxi Driver + a passenger. Maybe some kind of robbery or car chase included? Watch and get inspired!

I have: Cam, Optics, Car, CC
Result: 2048 x 768


Video Samples shot with the rehousing

ja spinn i dennOptical performance Test - EXA Pentacon 135mm f2.8 + Rathenower Rectimascop 48 + Rectilux 3FF-W
shooting specs: GH4 UHD VLog, transocded to prores into Resolve 1080p: ColorGHear LUT + color boosted + 2 corrections + edited in FCPX
Music: Kevin MacLeod - Deep Horrors