p.1 #4 · Will someone create an EF to SA adapter with electronics contacts.
Ian.Dobinson wrote:
i'm not sure an adapter could be done. but I know that some have converted the SA mount on the body to EF.
Yes, I am aware of Sigmacumlaude's project to convert SD bodies SA to EF. But the work requires major surgery and the finish is not that nice,
I am thinking since the flange distance between EF and SA are quite identical, an adapter should be possible. But loose auto aperture, exif and AF, etc. Conurus can convert Contax N lenses to EF and SA mounts. So maybe there is some way for EF to talk to SA electonics..,
That would be more convenient than modifying the body of the camera. Just a thought, I am no expert though....
p.1 #5 · Will someone create an EF to SA adapter with electronics contacts.
Sigma seems to copy the Canon EF communication. Because of this you could exchange the mounts - on the camera or on the lens side.
But the EF lens mount has a much wider diameter with the same flange back distance - that will not work. The other way round, Sigma SA lens on Canon EF is from this mount diameter probably, not for sure, possible.
p.1 #6 · Will someone create an EF to SA adapter with electronics contacts.
ZoneV wrote:
Sigma seems to copy the Canon EF communication. Because of this you could exchange the mounts - on the camera or on the lens side.
But the EF lens mount has a much wider diameter with the same flange back distance - that will not work. The other way round, Sigma SA lens on Canon EF is from this mount diameter probably, not for sure, possible.
So theoritically, it is just creating an adapter and conecting the contact pins on both sides. How difficult can that be? Can someone try?
The slight difference in the added lens distance, can that be fixed by in camera peripheral lens correction?
p.1 #7 · Will someone create an EF to SA adapter with electronics contacts.
ManWearPants wrote:
So theoritically, it is just creating an adapter and conecting the contact pins on both sides. How difficult can that be? Can someone try?
The slight difference in the added lens distance, can that be fixed by in camera peripheral lens correction?
well if the flange is the same distance then you've got nothing to work with to creat an adapeter or you will loose infintity. I did also see tha you can have a 1.4TC with an EF on 1 side and an SA on the other. (only an option with Tele lenses though)
p.1 #8 · Will someone create an EF to SA adapter with electronics contacts.
Ian.Dobinson wrote:
well if the flange is the same distance then you've got nothing to work with to creat an adapeter or you will loose infintity. I did also see tha you can have a 1.4TC with an EF on 1 side and an SA on the other. (only an option with Tele lenses though)
wow, that would mean 1.7 x 1.4. You lose all your wide angles. Yup, you are right on that part on the infinity unless the adapter can be kept thin.
It is silly for Sigma to reinvent a new mount. Just pay some royalties to Canon and they will see alot of SD cameras being sold.
p.1 #9 · Will someone create an EF to SA adapter with electronics contacts.
I think Sigma doesn´t want to pay roylities to Canon. As far as I know, Tamron does. Tamron had no problems with theri lenses for Canon. Sigma had some difficulties (older lenses wont stop down on newer DSLR cameras).
Furthermore it looks probably better when nobody sees that they copied only the mount and electronics. But the same electronics in the lens for EF and SA is cheaper.
p.1 #10 · Will someone create an EF to SA adapter with electronics contacts.
ManWearPants wrote:
I am thinking since the flange distance between EF and SA are quite identical, an adapter should be possible.
I think your logic is flawed. The nearly identical flange distance means there is no space for an adapter to be placed in between while retaining infinity focus. The flange distance of the lens to be adapter should be longer in order to allow space for an adapter.
p.1 #11 · Will someone create an EF to SA adapter with electronics contacts.
ManWearPants wrote:
wow, that would mean 1.7 x 1.4. You lose all your wide angles. Yup, you are right on that part on the infinity unless the adapter can be kept thin.
It is silly for Sigma to reinvent a new mount. Just pay some royalties to Canon and they will see alot of SD cameras being sold.
There's thin and then ther'es non existant.
And in my vague memories of when Sigma first brought out the SLR Camera (SA) I seem to remember reading that in the prototype stage it was meant to have an EF mount which is why its still very close relation, but maybe they had to change it for reasons like Canon not licensing the mount. Remember the likes of Sigma have to reverse engineer the mount and firmware for the canon fit lenses. I can only think of Kodak actually doing a non Canon body with a Canon mount. maybe some cross agreement allowed that in the early days of Digital.
Can someone try?