edwardkaraa wrote:
Great! Let him try this adapter and report back about the IQ
Dont be sadistic. All those adapters work more or less same. If lucky its 1.2x converter, if not its more.. As most teleconverters it cripples image quality and usually adds some nice CA.
Plastic element on the back of your very expensive lens, no way to change aperture. That should be a pleasant shooting experience.
I am surprised someone hasn't hacked a mount yet, though. Seems like something Conrus would be all over, given the Zeiss name. Maybe it's completely impossible.
Mescalamba wrote:
Dont be sadistic. All those adapters work more or less same. If lucky its 1.2x converter, if not its more.. As most teleconverters it cripples image quality and usually adds some nice CA.
Fully agree about Contax. The 28-85 and 35-70 are stellar.
Canon EOS's Flange Distance = 44.0mm.
Sony Alpha's Flange Distance = 44.5mm.
So principally you can do an adaptor with 0.5mm compensation but not vice versa.
Optical quality isn't mentioned and digital protocols, electronic AF and aperture aren't mentioned too, but as I know they are hacking now, let's wait.
contas wrote:
Canon EOS's Flange Distance = 44.0mm.
Sony Alpha's Flange Distance = 44.5mm.
So principally you can do an adaptor with 0.5mm compensation but not vice versa.
nope, not possible. i happen to have an eos and alpha mount sitting on top of each other here on my table and the bayonet diameter of the alpha mount is to large to fit inside an eos mount. even if it were possible, it ain't easy to machine a piece of aluminum or brass that thin without warping. i'd not trust an adapter that thin and the machining cost would be quite high.
you could do a mount replacement ala leitax, no aperture control though. didn't somebody here do that with a ZA 135/1.8.
sebboh wrote:
nope, not possible. i happen to have an eos and alpha mount sitting on top of each other here on my table and the bayonet diameter of the alpha mount is to large to fit inside an eos mount. even if it were possible, it ain't easy to machine a piece of aluminum or brass that thin without warping. i'd not trust an adapter that thin and the machining cost would be quite high.
you could do a mount replacement ala leitax, no aperture control though. didn't somebody here do that with a ZA 135/1.8.
Maybe you misunderstood my idea. If I have to do that I will order a CNC mechanik do a hybride mount , that fits Sony Alpha at one end and a 0.5mm shim all attached to an used canon EOS mount ( that I have many ).The cost of labor here is very affordable, so it encourages me do some conversions my self: contax N (645)--> Canon EF <-->Sigma SA.
contas wrote:
Maybe you misunderstood my idea. If I have to do that I will order a CNC mechanik do a hybride mount , that fits Sony Alpha at one end and a 0.5mm shim all attached to an used canon EOS mount ( that I have many ).The cost of labor here is very affordable, so it encourages me do some conversions my self: contax N (645)--> Canon EF <-->Sigma SA.
feel free to try but i'm telling you that you cannot put a functional alpha female mount on the back of a eos mount because it's physically impossible (the flanges on the sony bayonet have a larger diameter than the throat of the canon mount. you might be able to build it by putting gaping holes in the sides of the canon bayonet (not structurally advisable), but you still would not be able to mount an alpha lens to it and mount it on a canon camera because the alpha lens bayonet would block the attachment of the canon bayonet into the camera. if you've got the mounts handy get some calipers and measure them – there is no way to maintain that .5mm distance without one bayonet fouling the other.
I am a kind of practice so I say it's possible to do.
Now I will go step by step:
1- remove Alpha mount.
2- place the prepared 0.5mm shim that one side matched the rear of the lens (not the mount ), another side matched the EF mount , and attached to it by hided small screws.
That ALL I will do, now you can match Alpha lens to Canon EOS with out adding lens (like the item on ebay ) so you may keep the optics intact, ofcourse no AF and no aperture.Hope you get it.
adding: if the 0.5 mm shim is considered weak, you can remove all the already exist in len shims, you measure them and make a new shim with the thickness of sum of all those shims and remember +0.5mm .
contas wrote:
I am a kind of practice so I say it's possible to do.
Now I will go step by step:
1- remove Alpha mount.
2- place the prepared 0.5mm shim that one side matched the rear of the lens (not the mount ), another side matched the EF mount , and attached to it by hided small screws.
That ALL I will do, now you can match Alpha lens to Canon EOS with out adding lens (like the item on ebay ) so you may keep the optics intact, ofcourse no AF and no aperture.Hope you get it.
yeah, that will work fine but it's not an adapter it's a mount replacement (i've done many such conversions of various mounts to alpha mount myself). as ahamb mentioned wayne seltzer did one to convert a ZA 135/1.8 to eos.
Thanks to everyone for their ideas. I think I will
skip the Zeiss Sonnar idea. The Canon 24-70 MKII
is too expensive for the upgrade. I tried a Tamron
24-70 and found the results no less than the Canon.
