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10-01-2015, 12:45 AM   #1
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XR Rikenon 28mm f3.5 Aspherical Pancake

Recently acquired the lens from a local lens importer from Japan. Had been eyeing one from an online auction in Taiwan but got this instead. Now I got both twins - the 45mm f2.8 pancake as the other. Both are plastic build but with a metal mount. Both do not have the Ricoh pin. Does not have a smooth play compared to the takumars - and does not have half clicks in between aperture. It ain't a K28 f2 but will beat it in terms of weight as it is easy to bring it along on your shirt pocket if you need a wide angle.

Sample shots:

Forgot to mention: 1st sample pix is wide-open and all SOOC at f5.6 except the portrait which needs some curve adjustments. Notice also the purple fringing on the last picture - which most old lenses do have.

Edit: Posted the wrong portrait. That was taken by FA100 3.5. Corrected w/ additional pictures.

100% crop of flower:

ISO 1600 f5.6:

Last edited by mannyquinto; 10-03-2015 at 03:25 AM.
11-10-2017, 06:54 PM   #2
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QuoteOriginally posted by mannyquinto Quote
Recently acquired the lens from a local lens importer from Japan. Had been eyeing one from an online auction in Taiwan but got this instead.
In the meantime I've seen no other references to this (not so common) lens.
No reviews. No informations about the actual maker. AFAIK Ricoh switched from Pentax to Sigma well before the release of these two "pancake" lenses, but I don't know of any 3.5/28mm with aspherical element made by any 3rd party maker in the nineties...
An old post suggested Pentax design. Seems strange, as the closest Pentax project would be the FA 28mm, which also had an aspherical element if I'm not mistaken, though that was f/2.8 instead of f/3.5.
I've seen a few on Ebay, regularly at outrageous prices, given that's a fully manual lens with unimpressive plastic construction.
Does anybody own one. How is it?



Last edited by cyberjunkie; 11-10-2017 at 07:06 PM.
11-16-2017, 02:55 AM   #3
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The lens had a limited run (1996-97) that contributes to its rarity. Most Japanese sites hint that it was made by Cosina. From my recollection, RioRico who was very active back then was looking for this lens to be his carry-on light 28mm lens prime.

As an additional info, Ricoh introduced the 55mm f1.2, 45mm f2.8 and100mm f3.5 macro all on the the same year (1996). As far as I know, Cosina created the 55mm f1.2 and the 100mm f3.5 macro lens and manufactured and supplied it to different brands like Vivitar and Ricoh. That is why the Cosina, Vivitar and Ricoh version of the 55mm f1.2 are all the same lens and are different from the M42 Tomioka design which is its predecessor ( I believed there is a Cosinon 55mm f1.2 version). The Rikenon 55mm f1.2 was also manufactured for just a year (1996-97) that is why it is also rare. This is just my conclusion and would like somebody who actually knows the history if he ever reads this thread to comment.

Mounted on a Ricoh GXR:

On a K5ii:

Last edited by mannyquinto; 11-16-2017 at 06:13 AM. Reason: Added more info.
11-19-2017, 06:51 PM   #4
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Very nice. I've really enjoyed my P 28/2.8 and XR 70-150, fine classic manual lenses.

11-19-2017, 06:56 PM   #5
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Nice shots! One year of manufacture, wow, that means you were lucky to get a nice copy.

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