-M42 mount .A nice option but abit tricky finding room for 2nd to last elements to fit inside the M42 thread.It can be done i think...
- Nikkor mount.Sounds good but from discussions earlier in this thread there may be no hope of using it on nikon bodies (not enough room)
- Contax mount,Oly mount.These could be good but i have no knowledge about them
- EOS mount/EOS-M42 mount.A sensible option but very difficult to make screw holes through them, because you inevitable have to go through the trickiest part of the mount!I got around this by threading holes from the inside instead.
B)Spacing issues.
- Some like the nikkor mount may give infinity focus issues.
The EOS adapter i used could have been mounted further back with a small spacer,but in the end it only effects close focus ability by a very trivial amount.I preferred simplicity and strength so mounted it directly to the chassis
C) Mounting the rear element
- Using an EOS-M42 adapter for a mount is one of the easiest options because the threaded hole in the back gives a very convenient mounting area for the element holder **(see below)
D) Aperture adjustment (and calibration)
-Most of us use some kind of hand formed sheet metal which is then attached to the aperture adjustment ring somehow.
For this conversion i decided to try stiff wire instead.It runs all the way around the inside of the aperture adjustment ring which it is glued to.The ends are then formed into the right shape to engage the diaphragm lever.It works extremely well and looks neat but it did take awhile to get to the right shape...
I first decided to try this method because the plastic aperture adjustment ring on the lens looked way too flimsy.The wire reinforcement makes it much stronger
-Calibrating the aperture to the clickstops on the dial can be difficult with sheetmetal parts.Using the wire method makes it easy to get things just right
**If i was doing this all again i would try to do the following:
Use an M42 adapter -the type with the stop down flange- and have the flange hole threaded so that the rear element screws right in.
To work this would need a small spacer in front of the mount,but from my previous experience i\'m sure this would work in perfectly with what the mount needs anyway
Sep 18, 2009 at 08:31 PM
Previous versions of ronchappel's message #7545285 « FD 85L f/1.2: a real gem »
