Samyang 14mm / Sony Alpha mount / mount askew

[MatthewCromer]

I'm on my second Samyang 14mm.

Both lenses have been brilliantly, biting sharp in the center. The first one had a veiling contrast loss at f/2.8, but this second copy doesn't seem to have that issue at all.

The first one had inconsistent corner sharpness. I would get good corners on the right, then a bad corner, then good on the left, then bad. I finally figured out that the mount was not at tight as any of my other Sony Alpha lenses, whether Sony, Sigma, Minolta or Tamron. And that it was possible to push on the lens while mounted and fix the corner issue.

Anyway, the second lens appears to be optically even better, but still has the inconsistent right side corners issue, unless I push the lens to the right a bit while shooting.

I'm thinking to shim part of the lens mount to get the lens to mount properly without any corner issues. This lens is bitingly sharp, doesn't have veiling haze at f/2.8 and the corners are good when the lens is "flexed" to the right. I don't really want to keep playing "lens roulette" with any more purchases from Adorama / B&H with absolutely no guarantee I'll find another good copy next time.

Anyone else had this problem with the Samyang 14/2.8?

Anyone else

[NancyP]

I have heard that the Sony mount is inconsistent, that Sony used a plastic part that can deform, and that some people have tried replacing the Sony mount with a Fotodiox Pro "Tough" mount that is all metal (undoubtedly invalidating the warranty of the camera, if that is an issue). This is apparently "three screws out, swap mount, three screws back" DIY repair for even the simple minded user like myself. (I don't have the camera, but if a repair sounds simple to me - it IS simple.)

[MatthewCromer]

That's the sony E mount, I am referring to the Sony A mount.

I have four A-mount bodies and the lens is equally loose on all of them, unlike any of my other lenses.

I'm quite sure it's improper manufacturing tolerances in the mount on the lens itself - just wondering if anyone else has experienced this with the Samyang 14.

If the lens weren't so brilliantly good otherwise I'd send it back, but it simply blows away any of my other wide or ultrawide lenses, even in the corners, when the lens is pushed into proper fit.