Sonnar 100/3.5 - Modification for Full-Frame Use?

[Univer]

Hi All,

Having recently taken the plunge into full-frame (5DMkII), I now find myself confronting all the mirror-clearance issues many of you have dealt with...and benefiting greatly from your collective experience.

A lens I ultimately hope to use on the Canon is my Contax Sonnar 100/3.5, but I gather that's a "naughty list" lens. I gather, also, from comments I've seen in several places, that it's a relatively simple matter to remove the problematic rear tube/baffle. I've searched for specifics, but I haven't found any precise information. I was wondering if some kind colleague who's undertaken the operation might be willing to detail the procedure (and share any special cautions to be observed).

Thanks, as always, for your help!

Cheers,

Jon

[Olivier]

Hi Jon.

Did you solve the issue ?

I kept my 40D to be able to keep on using some of my lenses, like the Biotar 2/58 for instance.
The only way I found to use them on the 5D² is to use liveview which means the mirror is up. Just beware to make mirror down after setting the lens on a safe position for it.
Else, I use an extension tube but loose infinity.

[natebarnz]

My AEJ 100/3.5 works on my friends unmodified 5DmkII without any issues.

[vlousada]

[Orio]

Sometimes you read real bullshit on those uncompatibility lists.
I have two copies of the 3.5/100 and have used it with no problems on both the 5D and 5D Mark II.

[aoleg]

Both AEJ and MMJ copies of this lens worked fine on my 5DmkII. Before butchering the lens, try it with another adapter (big_is sells black hi-precision ones, which are quite good.)

[rafa1981]

Same for me, no mod needed.