Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-13-2017, 09:19 PM   #1
Senior Member




Join Date: Sep 2009
Location: Western PA
Posts: 136
Is this a Ricoh pin?

I just picked up this Sears auto 200mm f3.5 prime with M42 mount.
Is this a Ricoh pin or is it for the auto aparture? If it is a Ricoh pin, will it still cause a problem once it is
mounted on a M42 to K mount adapter?

Attached Images
 
12-13-2017, 09:34 PM   #2
Site Supporter
Site Supporter




Join Date: Mar 2007
Location: Christchurch, New Zealand
Photos: Gallery
Posts: 1,415
Auto Aperture pin. The Ricoh pin is further out on the lens mount.

Regards

Chris
12-13-2017, 10:19 PM   #3
Pentaxian
Thagomizer's Avatar

Join Date: Jun 2014
Location: London Ontario
Posts: 2,068
"Ricoh pins" are found on K mount lenses, not M42 ones.

http://farm5.staticflickr.com/4141/4921799547_b9c218a710_b.jpg

From what I've heard it's not the ones with a rounded end (like the one in the linked image) but the flat ended ones that are the problem. Haven't encountered it myself, though; others here undoubtedly have. I'm sure they'll chime in.
12-13-2017, 11:24 PM   #4
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 42,007
The pin in your photo is found on most M42 lenses. It is the aperture actuator pin and poses little or no hazard to your camera.*

The notorious Ricoh pin, on the other hand, is only found on the Ricoh-P K-mount variant and is on the mount face were it might foul on the AF drive pawl on Pentax AF cameras.


Steve

* The actuator pin on a small number of lenses may strike the power contacts deep in the KAF2 mount. If so, one can feel a light tick as the lens is mounted or removed.

12-13-2017, 11:35 PM   #5
Pentaxian




Join Date: May 2013
Location: Hertfordshire, England
Posts: 845
K-Mount Ricoh Pin:



Be aware that this is found not only on Ricoh lenses but also on some other third party film era lenses.
12-14-2017, 04:48 AM   #6
Senior Member




Join Date: Sep 2009
Location: Western PA
Posts: 136
Original Poster
Thanks for the replies. This is my first M42 lens on a K-Mount
so I just wanted to make sure.
12-14-2017, 10:05 AM   #7
Site Supporter
Site Supporter




Join Date: Jun 2008
Location: Idaho
Photos: Gallery
Posts: 2,348
That pin is engaged in older cameras to close the aperture when metering (usually pushing the metering button would press on this pin and stop the lens down to it's set value per the aperture ring). It was also used if the camera had a depth of field preview function so the subject could be seen through the viewfinder with the set aperture. The disadvantage of this type of system is that the viewfinder would darken while metering so continuous metering was out of the question.

In those older cameras, the camera would depress the pin while the picture was being taken, closing the aperture to the desired value, and once that was done, the aperture would pop back to wide open for viewfinder purposes.

The lens can be used with an adapter on K mount cameras, but the problem I encountered is that the pin isn't depressed so if the lens doesn't have a manual switch (located on the side of the lens), there's no way to get the set aperture (other than wide open) when taking a picture.

12-14-2017, 10:08 AM   #8
Pentaxian




Join Date: Mar 2015
Photos: Gallery | Albums
Posts: 6,381
QuoteOriginally posted by MrB1 Quote
Be aware that this is found not only on Ricoh lenses but also on some other third party film era lenses.
These may often be found with the designation P-KA/R or similar, as they were built to be compatible in feature set with both the Pentax-A and Ricoh's Rikenon-P series. My Kalimar 2X teleconverter (which I bought deglassed as an extension tube) is an example of such, but it has the rounded pin, which is safe.
12-14-2017, 11:46 AM   #9
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 42,007
QuoteOriginally posted by jeryst Quote
Thanks for the replies. This is my first M42 lens on a K-Mount
so I just wanted to make sure.
Better safe than sorry

You are not the first person to ask about the aperture actuator in relation to the Ricoh pin risk.


Steve
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
auto, k-mount, m42, pentax lens, pin, ricoh, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Samyang 18-28 and the Ricoh pin? ZombieArmy Troubleshooting and Beginner Help 11 12-02-2017 06:28 PM
I made a big mistake and need help - Ricoh pin kchamber4 Pentax DSLR Discussion 5 11-29-2017 07:49 AM
Does this Vivitar 28mm have Ricoh pin? ohaya Troubleshooting and Beginner Help 19 02-09-2016 11:03 AM
For Sale - Sold: Ricoh XR Rikenon 50 1.4 (non-Ricoh Pin) with Leather case. isb.deep Sold Items 4 05-19-2013 08:54 AM
For Sale - Sold: Ricoh 55mm f/1.2 (no Ricoh pin!), Voigtlander 40mm f/2 Ultron feilb Sold Items 4 11-22-2011 07:47 PM



All times are GMT -7. The time now is 08:35 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top