I know this has probably been answered

stevebrot · 08-21-2016, 08:03 AM

Originally posted by photolady95

So, not all Taks have the lever?

As far as I know, all M42 Takumars have manual aperture ability.

There is a small gotcha and it has little to do with adapting the lens to another mount. S-M-C and SMC Taks were designed to support open-aperture metering on some late Spotmatic bodies. Those lenses have a interlock mechanism that prevents full operation of the A/M switch when the lens is not mounted. It is not usual for a new owner to think their lens is broken due to this feature and there is the risk of damaging the lens if the switch is forced. The trick is to only use the A/M switch when the lens is mounted to the camera or adapter or when a rear cap is fitted.*

Steve

* There is a tiny pin on the mount face that must be depressed. Strangely, this pin may be the first example of where an Asahi/Pentax lens has potential compatibility issues with bodies from other makers. On some bodies (e.g. Mamiya/Sekor 1000 DTL) the mount flange has a screw hole that can foul the interlock pin if the lens is attached with the A/M switch in the A position.

Last edited by stevebrot; 08-21-2016 at 09:57 AM.

vonBaloney · 08-21-2016, 08:12 AM

Originally posted by stevebrot

Good question. My understanding is that it is a question of speed to open/close the iris. All those blades are hard to marshal if you need to have them all open/closed by the time the mirror finishes its travel.

Yeah, too many to activate in a snappy manner with a little pin. The 12 or 16 bladed lenses take a bit of strength which you don't really notice too much using your hand. The presets from Germany all seem to have a spring-loaded single ring with many blades (you press down on the ring as you turn it to move the preset stop, and then just turn the ring normally to actually open and close), and the Japanese presets I can think of have the double-ring, some with many blades, some with only 6-8.

Th double-ringed ones with not as many blades you can often just flick the second ring with a fingertip and it will sail to the correct stop. The Tomioka 60mm f/2.8 macro (more commonly found branded as a Mayima/Sekor or Yashinon) is like that. The Tele-Takumar 300/6.3 is a double-ring preset. (Tele-Takumar 300mm F6.3 Reviews - M42 Screwmount Telephoto Primes - Pentax Lens Reviews & Lens Database) Some other early Takumars are presets also I think. Probably all Super-Taks and SMC Taks and later are auto aperture...

Na Horuk · 08-21-2016, 09:10 AM

Only some m42 lenses have this switch. My Zeiss Flektogon 35mm has it, but my other Russian m42 lenses do not. Mainly I noticed that if it is set so the pin is sticking out, it can sometimes bump into the mount pins (especially the screwdrive mechanism if you have camera set to AF for CiF purposes or some holes in certain types of adapter) while you are mounting the lens. So I keep it in the setting where the pin is loose. I don't know if one is better for the lens mechanism than the other, though, and sometimes I worry that I am punishing the mechanism if I use it in Auto but do things by hand.

stevebrot · 08-21-2016, 09:10 AM

Originally posted by vonBaloney

the Japanese presets I can think of have the double-ring

Ditto for the Soviet lenses. Many have many blades and a stiff movement; there is no flicking there!

Steve

Last edited by stevebrot; 08-21-2016 at 09:37 AM.

stevebrot · 08-21-2016, 09:18 AM

Originally posted by Na Horuk

Only some m42 lenses have this switch. My Zeiss Flektogon 35mm has it, but my other Russian m42 lenses do not. Mainly I noticed that if it is set so the pin is sticking out, it can sometimes bump into the mount pins (especially the screwdrive mechanism if you have camera set to AF for CiF purposes or some holes in certain types of adapter) while you are mounting the lens.

Huh? The common aperture actuator pin is inboard of the mount face. The main issues with that pin when adapted are mirror interference on some (non-Pentax) cameras and, with Pentax AF2, potential interference with the power contacts in the mirror box. There are other pins, bumps, and contacts and such on various non-Pentax lenses that may not allow for a clean mount on other than the camera they were intended to fit. For that reason, it is always good to exercise care* on first use of a non-Asahi M42 lens on one's Pentax camera.

Steve

* By care, I mean fitting the adapter to the body first and slowly threading the lens onto the adapter while observing for potential points of interference. Common points of concern are pins on the mount face and protruding A/M switches on the lens body. It is my practice to fit the adapter to the lens first and then mount as usual to the K-mount body, but that method presents a hazard on unmount as the lens is unscrewed.

Na Horuk · 08-21-2016, 11:18 AM

Originally posted by stevebrot

Huh?

The Flektogon 35mm has a pin that sticks out of the mount. It is loose at one setting and stiff at the other button setting. This behaviour might be different from Takumars, as it was intended for other cameras (I dunno, I don't have any Takumars to compare it to), but that's how my copy works.
If I had the forum attachment space, I would upload a photo of it.

stevebrot · 08-21-2016, 12:56 PM

Originally posted by Na Horuk

This behaviour might be different from Takumars, as it was intended for other cameras (I dunno, I don't have any Takumars to compare it to), but that's how my copy works.

The "Electric" variant of the CZJ Flektogon 35/2.4 has three fat pins that that will contact the body mount face when adapted and one small pin that may also do so (depending on the adapter). I did a Google image search and found one example where all four had been non-artfully removed. I don't know if that is your lens (the Flek 35 had many variants in at least two different mounts spanning over three decades), but if it is, none of those pins are the same as the interlock pin found on S-M-C and SMC Takumars.

S-M-C Takumar from the back.

Most M42 lenses (including Super Taks) have the actuator pin (top of mount threads), but only the S-M-C and SMC Takumars have the smaller interlock pin (red arrow). When used with a K-mount adapter, the actuator pin is always inboard of the M42 mount opening and the interlock pin is always inboard of the K-mount opening.

Steve

Last edited by stevebrot; 08-21-2016 at 01:02 PM.

photolady95 · 08-21-2016, 12:57 PM

Originally posted by Na Horuk

If I had the forum attachment space, I would upload a photo of it.

If you use the "manage attachments" you don't need space. You can upload from your harddrive.

vonBaloney · 08-21-2016, 02:23 PM

Originally posted by photolady95

If you use the "manage attachments" you don't need space. You can upload from your harddrive.

You can still be maxed out and not allowed to upload.

**paulh** · 08-21-2016, 02:32 PM

Originally posted by Na Horuk

If I had the forum attachment space, I would upload a photo of it.

Free options: Flickr, Photobucket, Dropbox, Google Photos...?

photolady95 · 08-21-2016, 04:53 PM

Originally posted by vonBaloney

You can still be maxed out and not allowed to upload.

Really? I wouldn't know, I use flickr. OTH, I guess one would have to delete some of their attachments if they wanted to upload and their attachment space was used up. I didn't think about that when I posted the other.

08-21-2016, 09:18 AM	#20
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Na Horuk Only some m42 lenses have this switch. My Zeiss Flektogon 35mm has it, but my other Russian m42 lenses do not. Mainly I noticed that if it is set so the pin is sticking out, it can sometimes bump into the mount pins (especially the screwdrive mechanism if you have camera set to AF for CiF purposes or some holes in certain types of adapter) while you are mounting the lens. Huh? The common aperture actuator pin is inboard of the mount face. The main issues with that pin when adapted are mirror interference on some (non-Pentax) cameras and, with Pentax AF2, potential interference with the power contacts in the mirror box. There are other pins, bumps, and contacts and such on various non-Pentax lenses that may not allow for a clean mount on other than the camera they were intended to fit. For that reason, it is always good to exercise care* on first use of a non-Asahi M42 lens on one's Pentax camera. Steve * By care, I mean fitting the adapter to the body first and slowly threading the lens onto the adapter while observing for potential points of interference. Common points of concern are pins on the mount face and protruding A/M switches on the lens body. It is my practice to fit the adapter to the lens first and then mount as usual to the K-mount body, but that method presents a hazard on unmount as the lens is unscrewed. Last edited by stevebrot; 08-21-2016 at 09:53 AM.

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08-21-2016, 08:03 AM	#16
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by photolady95 So, not all Taks have the lever? As far as I know, all M42 Takumars have manual aperture ability. There is a small gotcha and it has little to do with adapting the lens to another mount. S-M-C and SMC Taks were designed to support open-aperture metering on some late Spotmatic bodies. Those lenses have a interlock mechanism that prevents full operation of the A/M switch when the lens is not mounted. It is not usual for a new owner to think their lens is broken due to this feature and there is the risk of damaging the lens if the switch is forced. The trick is to only use the A/M switch when the lens is mounted to the camera or adapter or when a rear cap is fitted.* Steve * There is a tiny pin on the mount face that must be depressed. Strangely, this pin may be the first example of where an Asahi/Pentax lens has potential compatibility issues with bodies from other makers. On some bodies (e.g. Mamiya/Sekor 1000 DTL) the mount flange has a screw hole that can foul the interlock pin if the lens is attached with the A/M switch in the A position. Last edited by stevebrot; 08-21-2016 at 09:57 AM.

08-21-2016, 08:12 AM	#17
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by stevebrot Good question. My understanding is that it is a question of speed to open/close the iris. All those blades are hard to marshal if you need to have them all open/closed by the time the mirror finishes its travel. Yeah, too many to activate in a snappy manner with a little pin. The 12 or 16 bladed lenses take a bit of strength which you don't really notice too much using your hand. The presets from Germany all seem to have a spring-loaded single ring with many blades (you press down on the ring as you turn it to move the preset stop, and then just turn the ring normally to actually open and close), and the Japanese presets I can think of have the double-ring, some with many blades, some with only 6-8. Th double-ringed ones with not as many blades you can often just flick the second ring with a fingertip and it will sail to the correct stop. The Tomioka 60mm f/2.8 macro (more commonly found branded as a Mayima/Sekor or Yashinon) is like that. The Tele-Takumar 300/6.3 is a double-ring preset. (Tele-Takumar 300mm F6.3 Reviews - M42 Screwmount Telephoto Primes - Pentax Lens Reviews & Lens Database) Some other early Takumars are presets also I think. Probably all Super-Taks and SMC Taks and later are auto aperture...

08-21-2016, 09:10 AM	#18
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Only some m42 lenses have this switch. My Zeiss Flektogon 35mm has it, but my other Russian m42 lenses do not. Mainly I noticed that if it is set so the pin is sticking out, it can sometimes bump into the mount pins (especially the screwdrive mechanism if you have camera set to AF for CiF purposes or some holes in certain types of adapter) while you are mounting the lens. So I keep it in the setting where the pin is loose. I don't know if one is better for the lens mechanism than the other, though, and sometimes I worry that I am punishing the mechanism if I use it in Auto but do things by hand.

08-21-2016, 09:10 AM	#19
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by vonBaloney the Japanese presets I can think of have the double-ring Ditto for the Soviet lenses. Many have many blades and a stiff movement; there is no flicking there! Steve Last edited by stevebrot; 08-21-2016 at 09:37 AM.

08-21-2016, 11:18 AM	#21
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Originally posted by stevebrot Huh? The Flektogon 35mm has a pin that sticks out of the mount. It is loose at one setting and stiff at the other button setting. This behaviour might be different from Takumars, as it was intended for other cameras (I dunno, I don't have any Takumars to compare it to), but that's how my copy works. If I had the forum attachment space, I would upload a photo of it.

08-21-2016, 12:56 PM	#22
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Na Horuk This behaviour might be different from Takumars, as it was intended for other cameras (I dunno, I don't have any Takumars to compare it to), but that's how my copy works. The "Electric" variant of the CZJ Flektogon 35/2.4 has three fat pins that that will contact the body mount face when adapted and one small pin that may also do so (depending on the adapter). I did a Google image search and found one example where all four had been non-artfully removed. I don't know if that is your lens (the Flek 35 had many variants in at least two different mounts spanning over three decades), but if it is, none of those pins are the same as the interlock pin found on S-M-C and SMC Takumars. S-M-C Takumar from the back. Most M42 lenses (including Super Taks) have the actuator pin (top of mount threads), but only the S-M-C and SMC Takumars have the smaller interlock pin (red arrow). When used with a K-mount adapter, the actuator pin is always inboard of the M42 mount opening and the interlock pin is always inboard of the K-mount opening. Steve Last edited by stevebrot; 08-21-2016 at 01:02 PM.

08-21-2016, 12:57 PM	#23
photolady95 Otis Memorial Pentaxian Join Date: May 2009 Location: Cruising the forum watching his back Photos: Gallery \| Albums Posts: 12,712 Original Poster	Originally posted by Na Horuk If I had the forum attachment space, I would upload a photo of it. If you use the "manage attachments" you don't need space. You can upload from your harddrive.

08-21-2016, 02:23 PM	#24
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by photolady95 If you use the "manage attachments" you don't need space. You can upload from your harddrive. You can still be maxed out and not allowed to upload.

08-21-2016, 02:32 PM	#25
paulh Site Supporter Join Date: Sep 2010 Location: DFW Texas/Ventura County, CA Photos: Gallery \| Albums Posts: 33,306	Originally posted by Na Horuk If I had the forum attachment space, I would upload a photo of it. Free options: Flickr, Photobucket, Dropbox, Google Photos...?

08-21-2016, 04:53 PM	#26
photolady95 Otis Memorial Pentaxian Join Date: May 2009 Location: Cruising the forum watching his back Photos: Gallery \| Albums Posts: 12,712 Original Poster	Originally posted by vonBaloney You can still be maxed out and not allowed to upload. Really? I wouldn't know, I use flickr. OTH, I guess one would have to delete some of their attachments if they wanted to upload and their attachment space was used up. I didn't think about that when I posted the other.