"Turn Vintage Still Lens into a Cinema lens" Canon FD 24mm f2.8 Rehousing by DoNotLeaN

Last crawled date: 3 years, 3 months ago

This custom lens re-housing is optimized for "Canon FD 24mm f/2.8 S.S.C.
I wanted to create a set of lenses that pay homage to the k35 Cine Prime. The k35 Cine Prime shares most of its optical design with the Canon FD lens, so we tried to re-house the Canon FD Prime lens to fit the Cine lens standard. However, it does not reach a level similar to the K35 Cine Prime due to several issues. The 24mm focal length K35 Cine Prime is similar to the optical design of the FD 24mm f1.4 Aspherical, but since this lens is rare and expensive and has radiation detection issues, I had to choose the FD 24mm f2.8 SSC lens.
The Canon FD lens is very attractive in terms of optical performance and cost-effectiveness, but it is also a lens mount method that is no longer used in new cameras. Of course, as with most vintage lenses, it can be attached to a digital camera through a simple conversion adapter extension tube. FD mount lenses are sometimes used by remodeling the'Canon EF mount method' in order to increase the utility. However, I personally kept the FD mount as it was because I didn't like the method of replacing the original lens mount with a new one. Canon FD's breech lock method is not very attractive for quick and easy lens change in still cameras, but it has an advantage as a sturdy and stable mounting method for video shooting, and I think it is one of the very well-made lens mounts.
Therefore, it is difficult to use it smoothly with Canon EF mount cameras, but I thought it could be fully utilized in recent digital mirrorless cameras (or cinema cameras that can change the mount method). For similar reasons, the stepless aperture portion of the aperture was not modified. There may be a shooting technique that utilizes the advantage of stepless aperture, but it is very limited and the sensitivity setting of a digital camera is very free compared to a film camera, which was very limited due to the fixed sensitivity of the film. So, I thought that the real benefit of sticking to the stepless aperture method wasn't great, so I didn't modify it to a stepless aperture (de-click).
This lens housing has an outer diameter of 114mm and the focus gear is also applied with a 0.8M Standardize Gear pitch applied to cinema lenses. (Outer diameter 114mm / 141T) It is a little burdensome because the outer diameter of the lens is large, but as the outer diameter of the focusing ring is enlarged, there is an advantage in fine tuning the focus. And it's useful when you use an auxiliary device exclusively for other cinema lenses.
It is designed to be securely fixed using several M5 and M4 standard grub screws. The filter step-up ring used on the front is designed to make it easier to use a general circular filter, and it is designed to stably fix the front part of the lens housing. It is a standard filter mounting screw standard on the front and has a diameter of 95mm.
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