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02-13-2010, 11:01 AM   #1
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Aperture pin on Helioses (Heliii?)

I'm looking to get into the world of M42 primes which (since I'm not looking to spend Flektogon or Takumar money) has led me to the ubiquitous Helios lenses. I'm aware that the ones with M in the model number don't have an A/M switch, and instead contain a screw which must be sealed to the 'in' position by some means in order for the lens to stop down (with the aperture ring) on Pentax DSLRs.

Quite a few lenses on evilbay have this already done (for example with superglue or some other sealant). Would there be any consequence for my camera body if this modification were to fail (ie the screw extended?) I'm just worried about the reports of odd screws on old lenses (esp. Ricoh ones) making them impossible to remove from the body.

02-13-2010, 11:24 AM - 1 Like   #2
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The pin on an M42 lens is for actuating the aperture. When mounted on a K mount camera with an adapter the pin will be inside the mount and so cannot get stuck preventing the lens being removed. The infamous Ricoh pin is on the back of the mount flange in a similar position to the pins on the back of pentas A and AF lenses and tends to get stuck in the focus screw drive. I have numerous M42 mount lenses and have never had a problem wuith any of them. The helios 44 is a great lens, you can't go wrong getting one.
02-13-2010, 11:33 AM   #3
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Cheers - just what I was hoping for!
02-13-2010, 09:42 PM   #4
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QuoteOriginally posted by MrCynical Quote
I'm aware that the ones with M in the model number don't have an A/M switch
44M actually has an A/M switch and, obviously, also has an aperture pin. The older 44 and 44-2 models have no aperture pin, so don't need a switch. The M just indicates the mount is M42 - the K variants are for K mount. I think all M42 variants other than 44 and 44-2 have the pin, with 44M being the only one having a switch.

If you get a lens with an aperture pin and no A/M switch, don't rush to superglue it - I can't find a link right now, but there is a method of keeping the pin pressed using a piece of q-tip. The method is mentioned here, but I can't find the link where I first read about it with more details about the procedure.

02-14-2010, 12:31 AM   #5
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QuoteOriginally posted by Laurentiu Cristofor Quote
44M actually has an A/M switch and, obviously, also has an aperture pin. The older 44 and 44-2 models have no aperture pin, so don't need a switch. The M just indicates the mount is M42 - the K variants are for K mount. I think all M42 variants other than 44 and 44-2 have the pin, with 44M being the only one having a switch...
This is not quite accurate...sorry...

The "M" refers to automatic aperture actuation on a supporting M42 body. Helios 44 without an M or K (except the 44-7, which pre-dates the 44M series) have a pre-set aperture. So, here is the summary:

Helios 44 Zenit M39, Mixed bag of characteristics...not commonly encountered...
Helios 44-D Zenit Automat-D mount

Helios 44-2 M42, preset aperture, 8-bladed iris
Helios 44-3 M42, preset aperture, 8-bladed iris, MC

Helios 44-7 M42, auto aperture actuation, 6-bladed iris (A/M switch?) (not successor to 44-3)

Helios 44M M42, auto aperture actuation, A/M switch, eight-bladed iris
Helios 44M-n M42, auto aperture actuation, no A/M switch, six-bladed iris, some have MC
Helios 44K-4 Pentax K-mount without KA contacts, six-bladed iris, MC
In addition:Hope this helps

Steve

Last edited by stevebrot; 02-23-2010 at 05:32 PM. Reason: Added 44-7, shuffled order for clarity
02-23-2010, 01:25 AM   #6
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The higher model numbers usually (not always) do indicate better resolution:

Helios-44 - 35/14 lines/mm
Helios-44-2 - 38/20 lines/mm
Helios-44-7 - 36/17 lines/mm
Helios-44М-4 - 38/19 lines/mm
MC Helios-44М-4 - 41/20 lines/mm
MC Helios-44K-4 - 42/21 lines/mm
MC Helios-44М-5 - 41/20 lines/mm
MC Helios-44М-6 - 45/25 lines/mm
MC Helios-44М-7 - 50/30 lines/mm

Source: zenitcamera.com
02-23-2010, 05:12 AM   #7
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I got my 77M-4 a few days ago, and I love it. Works great on my K20D, now all I need to do is learn how to MF properly (with no option to cheat and turn on AF like my DFA macros :P)
02-23-2010, 06:21 AM   #8
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QuoteOriginally posted by Laurentiu Cristofor Quote
If you get a lens with an aperture pin and no A/M switch, don't rush to superglue it - I can't find a link right now, but there is a method of keeping the pin pressed using a piece of q-tip. The method is mentioned here, but I can't find the link where I first read about it with more details about the procedure.
I have a Helios 44M-4. Picked it up along with a Pentacon (East German) 28mm/2.8 and a Zenit 35mm camera at a yard sale for $5. The Pentacon had the A/M switch; the Helios did not. With no modification, the Helios could only be used wide open. But the Q-tip fix mentioned in the link above was simple, quick, and effective, and can just as easily be undone if you ever want to use the lens with a film camera.

The "fix" is simple. Take a Q-tip (preferably plastic stemmed) and cut a length of about 1/4 inch from the stem. Locate the aperture pin on the lens mount*. Remove the 4 screws holding the metal plate on the mount. Use the cut portion of the Q-tip as a sheath around the aperture pin (it should just fit around the tip of the pin), then replace the metal plate. The increased diameter of the Q-tip is enough to keep the aperture pin depressed inside the plate.

*To find the aperture pin, turn the aperture ring to the narrowest aperture. If the lens stops down as you do this, you don't need the fix. If the lens doesn't stop down, press any protruding pins until you find the one that makes the aperture blades move.

02-23-2010, 01:13 PM   #9
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On my 44M I have left the pin in place and working as it should. I prefer to use the A & M switch to allow wide open focusing then stop down to meter and shoot.
02-25-2010, 08:20 PM   #10
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Out of curiosity, what does the "44" stands for, if anything?
02-27-2010, 03:03 AM   #11
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DONT put glue in the pin !!!

....it is super easy to fix. Take the 4* screws off the bottom. the pin will fall out as you lift the bottom off. Then place a 2.5mm piece of electrical wire insulation on the pin and slide it down to the base of the pin. Re-insert & re-assemble. I did mine, never done one before and it took me about 5 minutes.
03-01-2010, 06:51 PM   #12
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QuoteOriginally posted by ismaelg Quote
Out of curiosity, what does the "44" stands for, if anything?
I think it's just a model number. I'm not aware of any other meaning. There's a catalog of Russian lenses here. Helios lenses are listed with model numbers from 2 to 107.
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