At first glance, it seemed possible that the Mitchell 205 could be relatively easily converted for PL lens mounts. This would make the camera more versatile as there are more lenses available in PL mount than in BNCR mount. So I began the process of taking the camera apart to find out if the conversion is possible. What I discovered as I disassembled the camera are a number of ingenious modifications. Mitchell NC and BNC cameras both feature variable focal plane shutters, which was a feature cinematographers really liked. Several of the contemporary reflex conversions eliminated the variable shutter in order to accommodate the spinning mirror reflex mechanism.
![A close-up of the BNCR mount on the Mitchell 205 35mm camera](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-1-1024x1024.jpg)
![A close-up of the BNCR mount with the dust cover removed on the Mitchell 205 35mm camera](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-2-1024x1024.jpg)
In some of the 205 cameras, they were able to add the spinning mirror reflex mechanism and preserve the variable focal plane shutter. To accommodate both of these mechanisms, they had to carve away much of the camera casting and aperture plate to allow the spinning mirror to get close enough to the film plane so it could relay the entire taking lens light bundle to the viewfinder without vignetting. Because so much of the aperture plate was machined away, a ground and polished metal bar was added to the film side of the aperture plate as a reinforcement. The ground glass was mounted in an assembly that allowed it to swing out of the path of the aperture plate so the aperture plate could be removed for cleaning. All in all, several ingenious modifications to keep the old with the new.
![Holding up the PL mount to compare it to the BNCR mount on the Mitchell 205](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-3-1024x1024.jpg)
![Mitchell 205 camera with the BNCR mount removed](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-4-1024x1024.jpg)
![Mitchell BNCR mount removed from the Mitchell 205 camera](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-5-1024x1024.jpg)
![Holding the PL mount in the space where the BNCR mount was previously installed on the Mitchell 205](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-6-1024x1024.jpg)
The many hours investigating this showed me that there simply isn’t enough material to machine a new mounting surface for a PL mount without interfering with the spinning mirror and compromising the integrity of the camera’s main casting. Sadly, my conclusion is that a PL mount conversion is not practical with this camera.
![Discovering that there is not enough material on the camera casting to safely install the PL lens mount on the Mitchell 205 camera](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-7-1024x1024.jpg)
![The ground glass and movement in shooting position on the Mitchell 205](https://cinemagear.com/blog/wp-content/uploads/2023/07/mitchell-205-pl-mt-test-8-1024x1024.jpg)
![A 3 panel view of the ground glass on the Mitchell 205, first in shooting position, second being tipped out, and third fully tipped out](https://cinemagear.com/blog/wp-content/uploads/2023/07/Mitchell-205-Lens-Test-3-1024x1024.jpg)
![A two panel view of the aperture plate, left hand side shows the ground and polished reinforcing plate on the film side of the aperture, and the right hand side shows just how much material was machined away to make room for the spinning mirror on the back side of the aperture plate in the Mitchell 205](https://cinemagear.com/blog/wp-content/uploads/2023/07/Mitchell-205-Lens-Test-4-1024x1024.jpg)