VIVITAR Wide Angle 28mm F 2.5 

Focal length: 28mm
Mount: M42/T2
Aperture: F 2.5 - F 22
Min focus distance: 0.30m
Length (from flange): 60mm
[+ 27mm for the adapter], rear element protrudes 8mm, focusses internally
Diameter: 65mm
Weight: 385gr. with T2/M42 adapter

Some pictures:

A7 and the lens.

Sample pictures: You may click on the sample image (except closest focus) for full resolution. The full resolution image opens in a new window, so you can keep it open for comparison. Focus is on the satellite dish to the right of the big solar panel near the center of the photo.

F 2.5.

F 8.

F 22.

Closest focus
is only 14cm from outermost edge of the lens, F 8. Focus on the program wheel of the camera.

A very nice lens, wich opens a tad wider than 2.8.  Already at F 2.5 it's quite good, only a little softness at the edges, but there is vignetting which disappears completely when stopped down (and which wasn't there on film as far as I remember). Stopped down it's fine in my opinion. It has good capabilities of close focussing. However it's quite big and heavy.