FD -> EOS: Mount Conversion vs. Adapter

Hey POTN,

I have been looking at picking up a fast 85mm prime lens, and have really been intrigued by some of the older manual focus lenses available at this focal range. Something in particular that caugh my eye is the old FD 85L 1.2. I have been doing some reading about adapters for these lenses, and since they have another glass element in the adapter, people have said that the image quality is really degraded. This got me thinking...

Would converting the mount cause the same image degradation as the adapter? I have seen a few FD 85L's with mounts converted for an EOS body and the price really makes me want to consider them. I have read about people using adapters for old super-telephoto FD L's without any loss in IQ, and I was wondering why the same couldn't happen with this lenses in this focal range.

If it doesn't work out, that's fine. I'll just pick up an old Contax CZ 85 1.4 Planar T* and an adapter (), but I just figured I would ask to hear some other people's opinions on the matter.

Thanks

Kyle

Avoid the adapters that have glass in them. There are a few people out there (I can put you in touch with them if you send me a PM) who have converted the 85 FD to EF with some machine work. One reason the 85/1.2 FD still commands big dollars. Lots of other 85mm lenses out there. See my gear list.

gasrocks wrote in post #6903501
Avoid the adapters that have glass in them..

...which is ALL of the FD-to-EF adapters! The problem is that FD mount distance to focal plane is different from EF mount distance to focal plane and forces the use of an optical element to make the mount distance suitable.

Wilt wrote in post #6903511
...which is ALL of the FD-to-EF adapters! The problem is that FD mount distance to focal plane is different from EF mount distance to focal plane and forces the use of an optical element to make the mount distance suitable.

I believe you can convert it without glass if you don't care about infinity. For some lenses, that would be acceptable.

Thanks for the prompt replies everyone, they are really appreciated.

Oh, and gasrocks - I have seen your gear list, and I think "envy" on my part would be a serious understatement

The main reason I asked this question is because I saw someone on FM selling a converted FD 85L for $400 shipped and have been trying to convince myself whether or not it is worth purchasing.

khnordeen wrote in post #6903539
The main reason I asked this question is because I saw someone on FM selling a converted FD 85L for $400 shipped and have been trying to convince myself whether or not it is worth purchasing.

I would say for one already converted, then it is worth it.

One of the main problems for an 85/1.2 on an adapter is that the adapter also magnifies the image and costs you some speed, which sort of undermines the whole reason for an 85/1.2.

^That's the kind of stuff I want to hear

There is only one other concern I have now...

Would there be any problem mounting this on my 1D? The seller stated that the mount would work fine for an APS-C camera, but not for FF, and he is unsure whether or not it will fit on an APS-H. Would anybody here happen to know? Thanks again.

Kyle

Don't buy anything from a seller that is unsure of what it will work with. And, ask about infinity focus, and any possible interference with the mirror.

Many years ago during the transition time(manual to auto)and for a very short time Canon made a nice adaptor that worked well. That is a long ago rarity and if seen these days is priceless. Find and purchase one of those and your all set!!!

Those adapters go for over $1K and you still have to deal with a 1.2x crop factor. So, not an ideal solution. Besides, the only real reason to get an FD lens converted IMO is for bokeh. Modern lenses will have so much better sharpness, etc.

khnordeen wrote in post #6903471
Hey POTN,

I have been looking at picking up a fast 85mm prime lens, and have really been intrigued by some of the older manual focus lenses available at this focal range. Something in particular that caugh my eye is the old FD 85L 1.2. I have been doing some reading about adapters for these lenses, and since they have another glass element in the adapter, people have said that the image quality is really degraded. This got me thinking...

Would converting the mount cause the same image degradation as the adapter? I have seen a few FD 85L's with mounts converted for an EOS body and the price really makes me want to consider them. I have read about people using adapters for old super-telephoto FD L's without any loss in IQ, and I was wondering why the same couldn't happen with this lenses in this focal range.

If it doesn't work out, that's fine. I'll just pick up an old Contax CZ 85 1.4 Planar T* and an adapter (), but I just figured I would ask to hear some other people's opinions on the matter.

Thanks

Kyle

The Contax Carl Zeiss Planar 85 f/1.4 is probably a better lens than the Canon FD 85 f/1.2L. Sure 1/3 of a stop speed loss but the Zeiss is a ridiculously sharp lens. And the C/Y mount adaptors do not need glass elements (same for M42 and Pentax K mounts), so you won't be costing yourself IQ.

I was looking for an FD 85 f/1.2L myself but (after missing some well priced ones) found them to be about 500-700 bux - well at least the ones in great condition. I opted for the Helios-40-2 85mm f/1.5, which is a russian copy of the CZJ Biotar 1.5/75. Its an excellent CZ design that the russian factories manufactured in the 60s/70s. The Biotar 1.5/75 and the Helios-40's have a very unique bokeh that "swirls", because when wide open the aperature blades arent exactly round - some people love it (me!) and others don't.

Do some searches on Helios-40-2 and Helios-40 and Biotar 75. Its a M42 mount lens and works flawlessly. (Note: the Helios-40 is an M39-mount lens and needs to be adapted to M42 with a ring to mount as an M42 to Canon).

-Alan

Caution on the Helios. Some do not like the "different" bokeh it can produce. It is known as a portrait lens, but not generally known for sharpness.

Wilt wrote in post #6903511
...which is ALL of the FD-to-EF adapters!

Not entirely true. I picked up a plain-jane FD-EOS adapter (no glass) in order to mount an old Novoflex bellows on my 5D. Since its strictly for macro work, there's no need for infinity focusing, so the plain-jane without glass works just fine.

Its kinda odd...I'm able to use a plethora of alt lenses on my EOS gear (Oly, Zeiss, Leica,Nikon, etc) but not any of my old Canon FD gear. Go figure.

Bare naked:

TheHoff wrote in post #6903523
I believe you can convert it without glass if you don't care about infinity. For some lenses, that would be acceptable.

For someone who worked exclusively at macro and very close distances!

I should have inserted the word 'at infinity' for you wiseguys!

Wilt wrote in post #6904765
For someone who worked exclusively at macro and very close distances!

I should have inserted the word 'at infinity' for you wiseguys!

We forgive you. Your original post was about 500 words short of normal so some omissions are expected