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12-27-2017, 01:33 PM   #1
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Vivitar 28-105mm 1:3.5-4.5 Macro P/K-A R-P/K

Hi All,

I recently got this lens and wondering what i need to do to mount it on K-x or K-50.

I tried to mount it on k-x and it didn't feel right and hence i didn't force it.

Appreciate any help.


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12-27-2017, 01:47 PM   #2
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Nasty-looking hit to the filter threads. Hopefully it will focus correctly.
12-27-2017, 01:54 PM   #3
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and here

(PS this lens has the "ricoh pin" which can cause the lens to jam on the camera, howevr I think it is the retractable one - just move the aperture ring out of the "A" position)
(PS2 to get that filter thread dent out use a shaped hardwood former and a small hammer. Support the lens end with eg putty/bluetack/plasticene. Tap judiciously)

Last edited by marcusBMG; 12-27-2017 at 02:20 PM.
12-27-2017, 02:07 PM   #4
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A couple of issues to be aware of.

The flange that is protecting the aperture arm is pretty long and will probably need to be shaved down. I don't know about the K-X specifically but on the Kaf2 mount there are a pair of contacts on a small plastic protrusion located just inside the lens mount flange on the bottom side of the mirror bow. Originally for the power zoom feature but now used for auto focusing on lenses without screw drive. As you turn the lens while mounting it this flange looks long enough that it might contact that piece. If you feel any resistance while mounting the lens, stop as the flange can damage these if forced. I know from experience with an older Sigma lens and a brand new K10D many years ago.

Also, it's hard to tell from the picture, but this lens MIGHT have the dreaded Ricoh pin. At the 4 o'clock position in your third picture from the top there is a small contact. If that contact is a pin which extends below the mount, it will need to be removed before attaching the lens or the pin will get stuck in the auto drive socket on the camera body when you mount it and it is a bear to get the lens off once this happens. If on the other hand the contact is a small rounded ball bearing type connection you should be fine.


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