Ricoh Pin and Ricoh R/K mount

When pin sticks out too long
Jamming is more likely to occur

I have a Cosina 24mm f/2.8 with 'A' setting and with a P/K-AR mount that can be used in both Pentax K mount with 'A' aperture or the Ricoh camera such as Ricoh xr-p that has multi-programmed mode. If Ricoh pin is found to be long as seen on this picture, you should be concerned and be alerted with pin jamming problems. Not all Ricoh pin will jam but those that stick out long enough as the above picture will jam on the AF/MF connector on Pentax bodies that have AF and MF switch.

On my Cosina 24mm f/2.8 or some versions of Sigma 24mm f/2.8 ultra-wide lens rear mount, you should see two golden contacts, one on the far end is the Ricoh pin where one along with the electrical contacts is probably for the A metering contact in Pentax K-mount. Your lens can be used in both Pentax KA mount in 'A' setting. And it beats the others with an addition of 'P' with a Ricoh pin that allows you to use the special Ricoh programmed (or multi-programmed) mode in Ricoh xr, xr-p, kr-20sp, kr-30sp and any other Ricoh cameras with P settings. The Vivitar/Cosina 24mm f/2.8 in P/K-AR mount is found safe with Pentax bodies as the pin is small and retractable

The reason why some (not all) Ricoh lens with P pin may get stuck half-way is that the pin can get stuck onto the AF/MF switch on digital and AF film bodies. Once it gets stuck and it will appear that you can't slide it further, try gentle wiggle as the first step to overcome a stuck pin. The one possible and quick resort is to switch AF/MF switch on digital body to push the pin out and slide the lens further to lock in the properly mounted position. If your Ricoh lens has the P/K-AR mount signature, it is likely to work in both Pentax K-A and that in Ricoh P cameras that have special default Program (P), Programmed Action (PA) and Program DOF preferred (PD) modes such as those available in Ricoh xr-p.

Ricoh pin in Access zoom
though retractable sticks out too much
that likely cause jamming
Ricoh pin and Rioch P/K mount, ricoh xr-p

Access R/K mount on left
Cosina 55mm f/1.2 PK-mount on right
Ricoh pin pointed by red blower tip on bottom left
Ricoh pin and Rioch P/K mount, ricoh xr-p

A ricoh R-K lens without the Pentax A, the designated P setting is for Ricoh Programmed mode, the equivalent of Pentax A but the P setting can't be used as 'A' on Pentax K body, those Rioch only R/K lens can only be used stopped down in digital K-bodies.

P-MC with P for programmed mode
on an Access branded lens for Ricoh xr-p film cameras
The P pin is long though retractable
Will jam on K-x
Usually a wiggle and turn
frees the jamming
Ricoh pin and Rioch P/K mount, ricoh xr-p

Aperture ring has P setting
Ricoh pin and Rioch P/K mount, ricoh xr-p.

Ricoh xr-p camera
PA, P, PD selector
PA: action
P: normal program
PD: DOF preference for sceneryricoh xr-p
Ricoh xr-p and
Kodak Professional BW400CN
ricoh xr-p

And for those Ricoh or Rikenon lens that are pre-dated the xr-p time without the support of Programmed mode, those Ricoh lenses are more likely to share the same K-mount as Pentax.

Impressions & Notes:
  • Not all R/K mount with Ricoh pin will get lens stuck. Even when the Ricoh pin is found retractable and that it is a ball head type of pin as shown in this blog post, it really depends on how long it sticks out.

  • For K-mount bodies without auto focus, likely a Pentax film body such as Pentax SuperProgram, the ricoh pin will not be an issue as the jamming happens on the hole that corresponds to the AF/MF switch connector.

  • For digital bodies, the pin may get stuck in AF/MF pin position on the KAF2 crippled mount on digital body.

  • Usually a gentle wiggle will free the pin and you can slide the Ricoh lens all the way to mount properly

  • A quick and effective resolution if the pin is really stuck is to switch AF/MF switch on digital body and a wiggle on the mount so that the pushing up of AF/MF pin from the digital bodies have a chance to push the retractable Ricoh pin out

  • Ricoh/Riknenon lens that are pre-dated the time of Ricoh xr-p should not have this Ricoh pin and should be safe to be used as a regular K-mount lens.

  • For those lenses that have P/K-AR mount type, they usually have two golden contacts, one around the electrical contacts for the 'A' aperture passing and the other is the Ricoh P pin that is used to communicate with Ricoh xr-p in P (default programmed mode), PA (Programmed Action mode) for action shots, PD (programmed Depth preference mode) for scenery shot.

  • For Ricoh R/K lens, those can be used like a K-mount lens in a film body. In digital bodies, Av mode can't be used as those R-K lens don't have the contacts for 'A' aperture communication but they can be used with stop-down metering.

  • I have found that the Access zooms that I have do have retractable pin but the pin sticks out longer and I found them jamming in my K-x.

  • A careful wiggle frees the lens from the jamming

  • For those bigger P pin, one has to perform modification in either removing the pin or use a file or some other means to shorten down the pin.



teson said...

Thanks for the information,
just was I was looking for.

Blogs are useful.


photogerald said...

Thanks so much for posting this! I have a couple of lenses with the Ricoh pin which I've always wanted to try with my K20D, but have been afraid to because they may get "stuck". Actually, with my lenses I've always thought the risk of getting stuck was low, due to the pins being small, rounded, and spring-loaded. However, this goes against common accepted knowledge and I wasn't brave enough to risk it.

So I was quite glad to find your article amongst all of the other "doom and gloom" forum/blog posts about using Ricoh P lenses on Pentax AF bodies. This gave me the confidence to try out my lenses, unmodified:

Ricoh Rikenon P Zoom 28-100/4.0 Macro
Tokina AT-X 35-70/2.8 (62mm filter thread with Pentax-A setting and Ricoh pin)

I'm glad to say that neither has gotten stuck (I'll keep my fingers crossed), and I look forward to seeing how they perform on digital.

That said, one of these days I'll perform the easy modification of removing the Ricoh pin, just to be safe.

Anonymous said...

The modification to remove the Ricoh pin is very easy to do. It takes just two minutes, and is reversible if you ever want to sell the lens with the Ricoh pin intact.

Antoni Dani Wijaya said...

I have ATAN 35-70 F/2.5-3.5 and cannot fit to my Pentax K-x body.

Is there any other way to fit it in my Pentax K-x body. It seems stuck on AF motor in the body.

thanks before

Hin Man said...

I will suggest to toggle the AF/MF switch on the K-x body while wiggling and turning the lens at the same time. The pin likely jams around the AF/MF slot on the Pentax digital body and a toggle from MF to AF position may help to push the pin back while freeing your lens from the stuck position.

jyeat said...

After reading this I tried an old Soligor 100mm macro and it works fine. Thanks for the info.

Anonymous said...

Just wondering if anyone can help re using old RICOH lenses on new pentax we have KR10m Ricoh camera ( have also bought a new Nikon) the original lense is 35-70 rikenon p zoom lenses as well as a MC hanimax lens and a Koboron 300mm lense

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