Originally posted by kartongemi Thanksfor reply,
35 mm is not so wide and 16mm is fisheye. I had them because of m42 lenses are so easy to adapt to canon with eos adapter.
I love my zenitar
24mm going to be best choice for me,what is the original beonet of tamron? I checked ebay it must be a rare one.
The Tamron 24mm f2.5 is an Adaptall or Adaptall-II lens. You can buy mounts to fit different cameras. One of the M42 mounts is for the older M42 cameras, which would work and is more common. There is a specific Adaptall-II ES mount that would make the lens work like the later SMC Takumars on your Spotmatic-F. It may not be worth waiting for it but if you happen to see it, get that one.
There are Vivitar 19mm f3.8 and 20mm f3.8 lenses that are supposed to be OK. There's a Tokina 17mm f3.5 that you might see in M42 mount. These are really pushing the boundaries for early 70s lens technology, so you might have soft corners or other flaws.