Different versions of the Sigma 600mm 1:8 mirror lens

[bitsimman]

Hello everyone,

Yesterday I saw on a local trade-site some sigma 600mm 1:8 lenses. Since I wanted this lens for some time I decided to try to get one of those. The problem is that there are different versions of it. There was one with a canon FD mount, one with an Olympus OM mount and one with an Pentax bayonet mount (not sure about the exact mount).

After some searching I found that for the FD mount you seem to need an thick adapter which even has a lens while for the Olympus mount there just thin adapters without lenses and even seem to let you keep the infinity focus. I can't find much about the Pentax lens.
Now I am questioning myself what differences there might be between the lenses. for example about the space between the fitting and the maximum diameter. I have to mount it to an Canon 40D which has an build-in flash which might limit the maximum diameter.

Does anybody know about differences like that between the different versions of this lens?
Has someone experience with this camera and lens?
Is it even possible to get an adapter which let you keep the infinity focus?
Does an adapter produce more vignetting (or is the rear-diameter of the different versions smaller than the EF-mount thus forcing to crop the produced image)?

Greets,

Jan

[Donald]

Yesterday I saw on a local trade-site some sigma 600mm 1:8 lenses. Since I wanted this lens for some time I decided to try to get one of those. The problem is that there are different versions of it. There was one with a canon FD mount, one with an Olympus OM mount and one with an Pentax bayonet mount (not sure about the exact mount).

Hello Jan and welcome to CiC.

I apologise to being a bit confused by your question. I hope there are others on here who understand the issue better than I do and can provide answers.

For example, you say, "I have to mount it to an Canon 40D which has an build-in flash which might limit the maximum diameter." I don't understand what you think the problem is. Are you suggesting that you might be thinking about using the built-in flash with a 600mm mirror lens? I do not think that is a realistic option.

You also ask about the difference between the different versions of the lens. Again, I am wondering why this is relevant when you say you have a Canon 40D. The Olympus or Pentax versions can be of no interest to you anyway, can they?

Anyway, I hope you enjoy being a member of CiC and will become a regular poster on the forum.

[rpcrowe]

Hi Jan...

Welcome to CiC... It is unfortunate but, manual focus lenses from other manufacturers are easier to adapt to Canon EOS cameras than are the Canon FD manual focus lenses. I personally believe that this was an intentional ploy by Canon to prevent the generalized use of FD lenses (I had several) on EOS cameras and therefore spur the purchase of Canon EF lenses.

[bitsimman]

I don't understand what you think the problem is. Are you suggesting that you might be thinking about using the built-in flash with a 600mm mirror lens? I do not think that is a realistic option.

You also ask about the difference between the different versions of the lens. Again, I am wondering why this is relevant when you say you have a Canon 40D. The Olympus or Pentax versions can be of no interest to you anyway, can they?

Hello Donald (and everyone following),

And thank you for the welcome (and for the answers of course too)

What I meant was that the built-in flash sticks out in front of the camera about 1.8 cm. So, if the lens is from the fitting on 90mm in diameter it wont fit because of the flash-part sticking out in the front.
And indeed, I am not thinking of using the flash. That for the next reasons:
1: The build-in flash would never have enough range to lighten up some subject in front of the camera
2: The lenscap would throw a shade over half the subject (if not the lens itself)
3: The camera wouldn't allow a fast enough shutter if flash is turned on. (1/250 max or so)
4: considering the long lens which already makes the subject flat, adding flash would even make is worse by illuminating all shades on the subject thus making it appear more flat.

However you never asked the reasons I just gave them. Just to make clear that I understand I better don't use it.

@ rpcrowe:
that's ashame, though understandable that Canon wants continuity of their business.
I assume your answer is a hint to better not take the FD mounted version but another?

Today I did some research and found that some people claim to sell or make thin adapters for the FD mount which let you keep the infinity-focus. (EdMika adapter). Should I believe that this is possible (without damaging the mirror in my 40D. I guess that the adapter may go further inside the camera making it's 'thin-ness' possible)?
It also seems there are some K-mount adapters for EF.

Does one of you (or someone else) know some advises for this kind of adapters (or answers for my before-mentioned guestions)?

Greets,

Jan Oudman