What is the mount on this Vivitar 85-205mm F3.8 lens?

I recently purchased an old manual Vivitar Lense (10$!) to play with and cannot identify the mount. I just hacked a plastic body cap and put it on my Canon 450D (EF mount) and cannot get infinity focus nor can I focus farther then about 30 feet. This tells me that my cheapo adapter (about 5mm thick) puts the lens too far out. Identifying the actual mount of the lens would allow me to know the precise flange focal distance and go on from there.

I found this site detailing the lens but being real new to photography cannot find references to T Mount lenses anywhere. It has a small lever on the mount that can control the aperture (presumably from the camera body)

  • Vivitar 85-205mm 1:3.8
  • Macro Focusing Auto Zoom
  • No. 22539274
  • Filter diameter 58mm
  • Apertures from 3.8 to 22
  • Lens made in Japan Patents Pending N/F

The Whole Beast
Mount overview
Aperture Control
Mount Aperture Lever

What is the mount on this Vivitar 85-205mm F3.8 lens?

I recently purchased an old manual Vivitar Lense (10$!) to play with and cannot identify the mount. I just hacked a plastic body cap and put it on my Canon 450D (EF mount) and cannot get infinity focus nor can I focus farther then about 30 feet. This tells me that my cheapo adapter (about 5mm thick) puts the lens too far out. Identifying the actual mount of the lens would allow me to know the precise flange focal distance and go on from there.

I found this site detailing the lens but being real new to photography cannot find references to T Mount lenses anywhere. It has a small lever on the mount that can control the aperture (presumably from the camera body)

  • Vivitar 85-205mm 1:3.8
  • Macro Focusing Auto Zoom
  • No. 22539274
  • Filter diameter 58mm
  • Apertures from 3.8 to 22
  • Lens made in Japan Patents Pending N/F

The Whole Beast
Mount overview
Aperture Control
Mount Aperture Lever