problems mounting sigma lens onto a65

[misdehei]

Hi!

I wonder if anyone could give me any advice on a little problem I have with my new a65:

I've just upgraded to an a65 body and have several a-mount lenses left from previous minolta/sony cameras.

In this particular case I'd like to use a Sigma Super Wide II lens. The lens screws on, but it isn't very smooth doing so, and I'm worried I might do damage to the body. Once it's mounted it works fine, there are no electronic issues that I can see. It comes off, but again it doesn't feel very nice getting it off, although there is no scraping sound I feel it should be turning a lot more smoothly.

Should I avoid using this lens? If so, is there any way to adjust the barrel? I know it may sound silly, but it's as though it needs a little sanding??? Not that I'd want to do that myself, but are there repair shops that do that kind of thing? 

Thanks in advance

Barbara

[Bieomax]

I've had an older sigma lens like this, it is a little disconcerting when they are that tight.

Do you still have other alpha's ? is the fit tight on them also? as I'd be worried about modifying it an it then been slack on other camera's you have.

the following information is based on what I myself would try and thus as always with DIY you may cause damage to your lens mount, which if you attempt I hold no responsibility.

if its a metal mounted lens then I'd be tempted to try and slightly (very slightly) try and bend with some pliers the 3 bayonet flanges to increase the gap between the base of the lenses mount and bayonets.

Kind regards

Mark.

[misdehei]

hi mark,

thanks for your reply!

the lens fits fine on my old minolta slr and an on my A100, it's just this one it doesn't like. that being said, the a65 doesn't seem to have a problem with other lenses.

i don't think i'd dare try doing that myself, but i might take it to a shop and ask them to fiddle with it. it was second hand, and it looks like it wasn't treated all too delicately, but it would be a shame not to be able to use it at all. 

am i right in suspecting that mounting and unmounting that particular lense isn't very good for my camera? 

thanks, barbara

[Bieomax · Accepted solution]

Yes it's probably not overly good, as the mount on the camera is made from 3 parts as far as I remember, first is the metal mounting front plate, second is a plastic backing to that plate which has the bayonet interlocking parts on and then after that there is a thin metal insert which has bent bits in which act as a spring to take up any excess space (probably to counter any production tolerances when they make the lens bayonet)

So in my mind the springs will be quite tightly compressed with the sigma mount inserted. It's probably that with the camera's mount tolerances and the lens makers tolerances on the bayonet your getting abit close.

[misdehei]

thanks for your input!  i will take it into one of our local camera shops and let them check if anything can be done, in the meantime i'll avoid using that lense. you've been very helpful, thank you!