Minolta produced this lens since 2003. It's very common lens and it's not problem to buy a cheap one. Body is from plastic and has a rubbered zooming ring. Front element is rotating when focusing. It's full-frame lens, but can be used on APS-C DSLRs.
Specifications
| Focal range | 28-100 mm | ||||||||||||
| Minimum focus distance | 480 mm | ||||||||||||
| Aperture blades | 9 | ||||||||||||
| Filter diameter | 55 mm | ||||||||||||
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Depth of field and precision of focus
I tried depth of field at 28, 35, 50 and 100mm focal lengths. Lens has little backfocus, at least my one. Image might be much sharper. I attached image comparing detail from Sony SAL1855 and from this lens, both of them for maximum focal length and f/8. You can see that Sony SAL1855 is much sharper and has much better details.
50mm, f/5,6
100mm, f/8
SAL 1855 (55mm, f/8) vs. Minolta 28-100 (100mm, f/8)
Distortion and abberation
Distortion was tested at 28, 35, 50 and 80mm focal lengths. Lens has little barrel distortion at 28mm, at 50mm there is no distortion and it has a little pincushion at 100mm. Abberation is red and is visible mostly at corners when shooting wide open. It's much better when stopped down, but it never disappears.
35mm
50mm
100mm
Conclusion
I used this lens for about half a year. I was not satisfied with image quality. I didn't like it's colours and it was not sharp enough. In my opinion Sony SAL1855 kit lens are much more better than this. Rating 23/40.