[alamo5000]

I keep on hearing about the infamous Ricoh pin.

I have recently obtained a couple of Ricoh lenses and I want to know BEFORE anything happens what to look out for.

Does anyone have any photos of the Ricoh pin?

I don't want to screw it up.

Bought a Ricoh f1.4 lens and a f1.7 lens both 50mm. Both are "A series" or rather "P" series in Ricoh speak.

A picture or two is worth 1000 words...

I just don't want to inadvertendly put on a lens and then have the thing be stuck on there forever.

[interested_observer]

Evening, Here are the two sites that have what I consider to be the best information on the Ricoh pin. Hope they help....

• http://www.theatreofnoise.com/2008/05/ricoh-lenses-on-pentax-cameras-ricoh.html
• Hin's Tech Corner: Ricoh Pin and Ricoh R/K mount

[m42man]

I haven't any photos to hand, but it's pretty straightforward: if you have Rikenon-P lenses, then they'll have the Ricoh pin, and this should be removed before attempting to mount it on your DSLR. If you look at the lens rear plate, you'll see the red dot used to align the lens in the camera's mount. The Ricoh pin is close to being diametrically opposed to the red dot.

It's dead easy to remove the pin, assuming you have the right screwdriver (I think its a Philips head). Just undo the 4 screws which retain the back plate, and it's plain sailing - it takes no more than 5 minutes. Note that the wrong type or size of screwdriver runs the risk of mangling the screw heads, so be a bit careful.

[vonBaloney]

It's dead easy to remove the pin, assuming you have the right screwdriver (I think its a Philips head). Just undo the 4 screws which retain the back plate, and it's plain sailing - it takes no more than 5 minutes. Note that the wrong type or size of screwdriver runs the risk of mangling the screw heads, so be a bit careful.

I've just pulled them out with needle nose pliers.

[RioRico]

A PK-A lens has an A position on the aperture ring, for what Pentax calls Auto operation. A PK-AR or PK/R lens labels this position P or A(P), for what Ricoh called Program operation. More than a few 3rd-party lenses were built with PK-AR compatibility. I've seen such branded as Sears, Focal (K-Mart), Vivitar, and Promaster|Tamron.

All those I have personally encountered have a small, non-toxic button (or 'nub') instead of the dangerous pin. Some of these 3rd-party lenses were made by Ricoh but sold as house brands like Sears and Focal. I have seen a report that at least one Sears prime had the pin, but I haven't seen it in any of my Sears lenses. I'm sure that my Focal 135/2.8 was made by Ricoh but it has the nub, not the pin.

Hold the lens so the red dot is at the 12-o'clock position. The pin will be at about the 7-o'clock position. See the above links for pictures. Just be aware that *some* but not *all* PK-AR lenses have the dangerous pin.

[GibbyTheMole]

It's dead easy to remove the pin, assuming you have the right screwdriver (I think its a Philips head).

It is very easy to remove the pin... Just make sure you have a good #0 phillips head screwdriver. The ones found in cheap jeweler's screwdriver kits are useless, because not only are they made of soft metal which strips easily, the grips don't give you enough leverage to get the screw out. Use one of those, and you'll probably bung up the screw, the screwdriver, or worse yet, have it slip and hit the glass. Bad news.

You want one like this:



Better quality, & a big enough grip to give you some leverage. Use one of these and it's a piece of cake that takes less than 5 minutes.

Good luck,
Bobbo :-)

[boriscleto]

If the lens is made in Japan you will want a JIS screwdriver. The screws in lenses usually get stripped because they are JIS, not Phillips.



Micro-Tools Product Search Results

[Tom in Delaware]

I haven't any photos to hand, but it's pretty straightforward: if you have Rikenon-P lenses, then they'll have the Ricoh pin, and this should be removed before attempting to mount it on your DSLR. If you look at the lens rear plate, you'll see the red dot used to align the lens in the camera's mount. The Ricoh pin is close to being diametrically opposed to the red dot.

It's dead easy to remove the pin, assuming you have the right screwdriver (I think its a Philips head). Just undo the 4 screws which retain the back plate, and it's plain sailing - it takes no more than 5 minutes. Note that the wrong type or size of screwdriver runs the risk of mangling the screw heads, so be a bit careful.

I have a couple of Ricoh-P lenses and the 'Ricoh' pin on these is a rounded contact like the contacts on a Pentax A-series lens or later. This won't get stuck. I use them on my Pentax dSLR and autofocus Pentax SLRs, no problem. Some third party lenses, like Vivitar, used an actual pin. This will get stuck. Check the shape of the 'pin' or contact before you go to the trouble of taking the lens apart.

[alamo5000]

I have photos of the backs of the lenses I am getting. These pics were pinched from the seller.

I don't think I will be needing to disassemble the lens based on the photos and based on information obtained in other sources (Thanks RioRico)...

I see the contact thing on the back of the lens because they are A series.... but I think I am safe...(for now)...

[vonBaloney]

A PK-A lens has an A position on the aperture ring, for what Pentax calls Auto operation. A PK-AR lens labels this position P or A(P), for what Ricoh called Program operation. More than a few 3rd-party lenses were built with PK-AR compatibility. I've seen such branded as Sears, Focal (K-Mart), Vivitar, and Promaster|Tamron.

All those I have personally encountered have a small, non-toxic button (or 'nub') instead of the dangerous pin. Some of these 3rd-party lenses were made by Ricoh but sold as house brands like Sears and Focal. I have seen a report that at least one Sears prime had the pin, but I haven't seen it in any of my Sears lenses. I'm sure that my Focal 135/2.8 was made by Ricoh but it has the nub, not the pin.

Hold the lens so the red dot is at the 12-o'clock position. The pin will be at about the 7-o'clock position. See the above links for pictures. Just be aware that *some* but not *all* PK-AR lenses have the dangerous pin.

All of the ones that specifically are marked as "PK/R" or similar have a button (like an A contact) rather than a pin -- after all if it was being marketed for Pentax cameras, it wouldn't have a pin that makes the lens get stuck. So you'll see this button on old Vivitars, etc. So the pins generally are only to be found on actual Ricoh/Rikenon lenses. I've also had to remove pins from Mamiya/Sekor m42s (which usually also need other mods because the aperture ring overhangs the edge) -- I'm not sure it is in the same location as the Ricoh pin, but it will cause problems, so I guess there is also a "Mamiya/Sekor pin" out there. Bottom-line: check for pins on the bottom ring. But you can't miss them -- they are not hidden...

[RioRico]

I have photos of the backs of the lenses I am getting. These pics were pinched from the seller.

I don't think I will be needing to disassemble the lens based on the photos and based on information obtained in other sources (Thanks RioRico)...

I see the contact thing on the back of the lens because they are A series.... but I think I am safe...(for now)...

Those *look* OK. Easy way to find out: mount them! And if they get stuck, a thin 'feeler' gauge blade should be enough to free them. Do you feel lucky?

NOTE: These Pentax- and Ricoh-compatible lenses may be marked PK/A or PK/AR or something like that. But a lens marked AR or K/AR is KONICA, not PENTAX, and it WILL NOT WORK on a Pentax camera. Well, as a macro lens maybe, but it won't focus to infinity. Don't worry about it getting stuck. The only danger is to your budget. Many Konica lenses (Hexanon!) are highly regarded, and grabbed-up by NEX-NX-Q-etc users. Demand and prices can be high. You have been warned.

[alamo5000]

You guys make me nervous!

Do I feel lucky? No, not particularly.

If I won powerball I would have felt very lucky.

[Tanzer]

I have the Ricoh pin on a Quantaray f/2.8-4.0 28-70mm lens that a friend is loaning me. This lens was intended to work on both mounts; it mounts/dismounts quite easily on my K-5 and his K-20, you wouldn't even know it had the pin. In fact he didn't even realize it had the pin until I mentioned it. Anyhow as others have said, much has been said of a situation that when true (i.e., for real PINs which I think are cylindrical) can be a real pain, but for lenses which were meant to work on both bodies, is entirely harmless.

Anyhow, just my 2 cents, but that certainly looks like a "safe" version of the ricoh pin, as it has a rounded, spherical head. Try scraping your fingernail over the contact and if if springs inward easily and smoothly, it is safe. You can compare this to the other spring-loaded contacts on a new DA lens. The reason I say to compare, is that the other normal contacts on A, DA, and FA lenses also slide over the autofocus slot in the body when you mount the lens, exactly the same way, and those never get stuck, of course.

I think you are safe. Good luck!

[jimr-pdx]

I have photos of the backs of the lenses I am getting. These pics were pinched from the seller.

I don't think I will be needing to disassemble the lens based on the photos and based on information obtained in other sources (Thanks RioRico)...

I see the contact thing on the back of the lens because they are A series.... but I think I am safe...(for now)...

My 28/2.8P has that same sort of pin - more like a ball bearing than a pin. The dangerous ones actually protrude a few mm out the back, far enough to fall into the AF screw-slot and cause trouble. Mine like this have never been a problem, but my 28-100/4P had a long pin and needed surgery.

The Ricoh pin does not align with 'A' contacts and the P series is fully manual on Pentax dSLRs - although it will shoot wide open in Av mode (and other auto?). Note on the shot below the difference in location, with the mounting mark at 12 o'clock. The Rikenon-P is on the right, and the 'pin' is past the 6:00 position - the Sigma lens on top shows the 'A' contacts are all around 4:00-5:30 position. Also note on the Sigma 50 where the focus screw is; the proximity of the 'Ricoh pin' and the drive screw is the source of the trouble.

Interesting though, my Vivitar 28-105 (lower left) has the 'A' pins and also a pseudo-Ricoh pin too - hadn't noticed that before. Guess that's why the mount says R-P/K on it as well as P/K-A! Thanks for causing me to learn this, vonB and the rest of you!

[cali92rs]

This thread actually sprang up at a very good time for me. I just bought a Sears 28mm f/2.8 and it has the rounded contact, not the pin persay. I mounted it a few times yesterday. Although it felt a little "funny", maybe sticky is the right way to describe it, it came off with no issues.