Kiron 28-85mm f2.8-3.8 Zoom lens (on Olympus EPL1)

[SXR_Mark]

I got this lens for a small sum as the aperture was stuck wide open. The problem turned out to be a very bad case of oily blades, with no hope of making them free enough by simply exercising them. Thus, I had to open the lens up to clean the blades and this turned out to be quite a job. Basically, i ended up with the lens more or less completely disassembled. I also found some slight hazing on the second to last element (coating deterioration) and some slight surface damage to the element that sits right behind the aperture, probably caused by the oil vapour. This damage is quite light and only really visible when shining a bright light through the lens. Nevertheless, I wasn't very optimistic about how well it would work when I got it back together. Fortunately, it seems to work really well!

My time to do tests has been very limited and I've mainly been exploring the close focusing ability of the lens. At 28mm it will focus to a few cm from the front of the lens. Creating an optical design that maintains good performance in a wide ranging zoom lens to this sort of distance and with f2.8 aperture must have been a real challenge. But the Kiron engineers seem to have done an amazing job.

At f2.8:



100% crop



At f4



100% crop



Though the focus is not quite the same between the shots, I hope you can see the lens is not super sharp at f2.8, though its pretty good, and is excellent at f4

At f2.8 (focus on the double bud but missed slightly due to very thin depth of field)



At f4 (nailed the focus with this one)



The following at f2.8 (or wide open when FL not 28mm)





This one shows no colour fringing on the edges of the twigs. Wonderful.



Hey mister, this isn't your garden!



I should point out that I have applied a small tweak to the levels to give a bit of extra punch to the images, but things are still pretty good straight from the camera.

I hope the performance at longer FLs and longer distances holds up as well as this.

[SXR_Mark]

Pictures of the lens itself.

This shows it is quite large on the EPL1. it is also quite heavy, but feels well balanced. I used the hood shown for the above shots.

[SXR_Mark]

I think this lens was also sold as a Vivitar

http://forum.mflenses.com/vivitar-28-85mm-f2-8-3-8-t384,highlight,%2Bvivitar+%2B85mm.html

[Excalibur]

Kiron make some VG zooms, out of my five Kiron zooms only one had a stuck/sticky iris but after two years it seems to be working OK now