There are two zoom type with 1-touch and 2-touch format. I have used both and they come in either K mount and M42 mount. All have close focusing capability and close up happen in 70mm end and magnification ratio roughly goes to 1:4
I bought it for $40 and I got the two touch zoom in M42 mount for the Av mode. The K mount is just as good and very similar. If you look for this zoom, also look for the ones that pair with Vivitar/Kiron 1.5x or 2x matched multiplier as I have used the 2x multiplier. The Kiron has done a great job in the lens as well as the matched multiplier.
I reckon the 2 touch zoom share many IQ with the one touch but I prefer the 2-touch zoom for less mistakes in moving the zoom position while focusing. The best about the two touch zoom are as follows:
- very sharp, even wide open are sharp
- though 2-touch is bigger, but still relatively small to cover a useful range
- close focus is quite good due to good sharpness, when paired with diopter, it is like a 1:2 close up zoom lens
- f/3.8 is very capable for this zoom
- bokeh is alright, will be nice if softer
- slight tendency for bluish color
- built-in lens hood but not deep enough
Some close up with
Cosina 1:1 matched macro adapter
roughly 1:2 in the combo
Some casual street shots
The lens often goes low value and if you love manual lens zoom lens that don't break budget, this is a value lens to get from Kiron.