[Stavri]

A few days ago I bought a CZ Sonnar 85mm f2.8 in Rollei (QBM) mount for a good price. I thought converting this lens to either M42 or PK. I've done some messy conversion in the past, my Rollei Planar HTF 50/1.8 which I converted from QBM to PK was particularly ugly, the aperture as a results works half the time, the QBM conversions being notoriously hard.

I do have a Voigtlander Color Ultron 50mm f1.8 in M42 mount, an truly amazing performer. This lens has the pedigree and excels at everything, sharpness, low aberration, beautiful bokeh, great voigtlander colors. Unfortunately ever since I've gotten the 8-element Super-Tak 50/1.4 I have been playing less with the Ultron. With the arrival of the Sonnar 85/f2.8 I know I can essentially swap the rear mounts between these two lenses, but if I do so I'll lose the use of the Ultron to gain that of the Sonnar, hence the dilemma.

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Last edited by Stavri; 03-25-2015 at 04:11 PM.

[Na Horuk]

Wait what? Wouldn't it make more sense to get a donor mount from a broken or hazy lens or better yet, just a mount that you get separately? People usually use a flanged m42 to K adapter
No need to ruin a perfectly good lens to gamble with a conversion.

[Stavri]

Wait what? Wouldn't it make more sense to get a donor mount from a broken or hazy lens or better yet, just a mount that you get separately? People usually use a flanged m42 to K adapter
No need to ruin a perfectly good lens to gamble with a conversion.

The VL Color Ultron 50/1.8 and the Color Dynarex 85/f2.8 made by Rollei Singapore are identical to the CZ Planar 50mm f1.8 and Sonnar 85/2.8 for Rolleiflex. It's not a gamble, but a somewhat straightforward swap. The M42 Voigtlander lenses are somewhat rare, the 50/f1.8 can be found more easily than the 85/f2.8 (which sold for over $450 last time I tracked one down in 2013.) Hacking the QBM by milling, lathing etc is very hard, one needs a proper metal shop, but transferring mounts between the lenses should be easier. I could go around opening hazy Meyer Orestors or Pancolars to see if the mounts are compatible but I know the Color Ultron might be my best option. The questions is should I do it...

ps. If anyone has a hazzy or fungusy color Ultron or M42 dynarex laying around let me know

[stevebrot]

I would suggest you leave that poor Ultron alone. The VL is a valuable lens in its own right.

Steve

[redcat]

oh my oh my, please don't kill the Ultron >_<

[stevebrot]

oh my oh my, please don't kill the Ultron >_<

I think we need to start a petition drive.


Steve