My girfriend mounted a Pentax PKA fit Sirius lens (135mm, f2.8 macro from 1984) on my K-3 and can`t get the lens off now! According to her she twisted it on without any force but quick release button is not releasing the lens.

Any ideas?

[stevebrot]

Hi

It is possible the lens is combination PKA and Ricoh P. If so, it would have the infamous "Ricoh Pin" which may extend into the AF drive well on the body making the lens very difficult to remove. Lenses with the Ricoh pin are quite safe with manual focus Pentax cameras of the time. It was only after the introduction of auto-focus to the Pentax line that the problem arose. Combo PKA/KR lenses are not uncommon and there is usually some clue in the lens markings and/or the aperture ring ("P" rather than "A" as the program exposure position).

Removal of a stuck lens may be difficult to the point of dismembering the lens. Some have reported success with a thin "feeler gauge" commonly used by auto mechanics. Google "ricoh pin feeler gauge" for links on how it is supposed to work. The link below has detailed instructions from someone who was successful (keep reading on down the page):

Ricoh pin removal {tag}: Pentax SLR Talk Forum: Digital Photography Review

Good luck.

Addendum: As was pointed out in comments below, some variants of the KR mount use a pin that retracts when the aperture ring is off the "A"/"P" position. In addition, sometimes it is enough to put the AF switch in the "AF" position. That may press the pin up enough to allow the lens to be "wiggled" off.


Steve

[robgski]

I've had a similar problem with a different lens. Make sure the aperture ring is not set to the "A" setting. keep the lens pointed down, press the release button and gently twist the lens loose.

Good luck.

[marcusBMG]

It's these early PK-A/R mounts that can have the problematic ricoh pin IMO, almost all later ones have a ball, rather than a pin, that doesn't catch.

Make sure the aperture ring is not set to the "A" setting.

+1, it's in "A" position that the pin is extended out.

press the release button and gently twist the lens loose.

You can reasonably safely use a judicious amount of rotational force.. and "wiggling" might help. The danger is that you unintentionally tilt/lever the lens and start strippng camera side mount attachment screws out of their (plastic!) threads.

[stevebrot]

Make sure the aperture ring is not set to the "A" setting. keep the lens pointed down, press the release button and gently twist the lens loose.

+1, it's in "A" position that the pin is extended out.

This is good advice, though the pin may or may not retract. It depends on the lens.


Steve

[niceshot]

wow what a bummer, hope i never do this by mistake. I always studie a lens before mounting it. But it could happen to anybody, curios to the out come

[noblepa]

You can reasonably safely use a judicious amount of rotational force.. and "wiggling" might help. The danger is that you unintentionally tilt/lever the lens and start strippng camera side mount attachment screws out of their (plastic!) threads.

I thought that all Pentax dslrs had metal frames, covered by a plastic skin. If so, would the screws be threaded into the underlying metal, rather than the plastic skin?

[marcusBMG]

I thought that all Pentax dslrs had metal frames, covered by a plastic skin. If so, would the screws be threaded into the underlying metal, rather than the plastic skin?

Judging from my in-pieces K-r (need spare parts anyone?), and the threads here on PF re bodies that have had the lens mount dislodged, the metal lens mount on the camera on many models is resting on a plastic frame and held on by screws that engage just with that plastic frame.
But I am not familiar with the K3.

[stevebrot]

I thought that all Pentax dslrs had metal frames, covered by a plastic skin. If so, would the screws be threaded into the underlying metal, rather than the plastic skin?

Judging from my in-pieces K-r (need spare parts anyone?), and the threads here on PF re bodies that have had the lens mount dislodged, the metal lens mount on the camera on many models is resting on a plastic frame and held on by screws that engage just with that plastic frame.
But I am not familiar with the K3.

The screws for the K-3's mount engage the mirror box assembly which is made out of some sort of structured polymer. This is obvious from the various cut-away photos on the Web. Unless something has changed, I believe the same is true for all current model Pentax dSLRs with the exception of medium format models. On those cameras, the mirror box is alloy.


Steve

[Theov39]

Did you get the lens off?

[niceshot]

Did you get the lens off?

Guess he isn't going to answer

[Mehis Replik]

Sorry for the mega late reply! It was indeed the dreaded Ricoh pin (KR on aperture ring). So basically did what stevebrot suggested, put body to AF mode and wriggled it free (used my girlfriends nail filer between the body and lens). 45 minutes struggle it was.

Thanks again guys

[niceshot]

Kool beanz

[csa]

Thanks for letting us know! Glad you got the lens removed!