M42 lens

ckswong · 09-17-2012, 06:47 PM

So I just got a Meyer optik 50mm 1.8 for 50 dollars today and noticed it doesn't have a manual switch on it. My question is can I mod it somehow for it to auto stop down without depressing the pin in the back of the lens?

**jatrax** · 09-17-2012, 08:11 PM

I have heard of people super gluing the pin down, or using various things to hold it in. Read here:
https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/51749-m42-auto...ification.html
https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/101606-how-fix...anual-one.html

**Lowell Goudge** · 09-18-2012, 10:11 AM

I do a mod for lenses that do not have the switch, using a short price of pltic tubbing to block the pin in the depressed mode. The other option is to get an M42 adaptor that has a flange to depress the pin when mounted, although note these do not work with lenses made for the Spotmatic F or ES II which have a little bump on the bottom. (specifically SMC taks)

If I find the photo I posted of the mod I will put a link here. Note the tube is about 1/8 inch ling (3 mm for the imperial impared) and I find the end of a ballpoint pen refil to be the perfect material

ckswong · 09-20-2012, 09:10 PM

thanks guys, that was exactly what i was looking for. i was at work on my phone and google seemed to come up with nothing which was odd. but i also googled it at home and behold! all the answers lie there. thanks again.

09-17-2012, 06:47 PM	#1
ckswong Forum Member Join Date: Apr 2012 Posts: 71	M42 lens So I just got a Meyer optik 50mm 1.8 for 50 dollars today and noticed it doesn't have a manual switch on it. My question is can I mod it somehow for it to auto stop down without depressing the pin in the back of the lens?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
M42 lens in Av	userage	Pentax SLR Lens Discussion	21	04-11-2012 03:34 AM
M42 Lens with small base	Odinz	Pentax SLR Lens Discussion	20	04-08-2012 11:43 AM
m42 Lens Adapter - Zykkor M42	reivax	Pentax SLR Lens Discussion	4	02-28-2012 11:00 PM
Restoring an old m42 lens	ismaelg	Pentax SLR Lens Discussion	9	10-03-2011 09:33 PM
Attaching M42 adapter permanently to a lens	Tim_R	Pentax SLR Lens Discussion	9	10-07-2010 05:45 AM

09-17-2012, 08:11 PM	#2
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	I have heard of people super gluing the pin down, or using various things to hold it in. Read here: https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/51749-m42-auto...ification.html https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/101606-how-fix...anual-one.html

09-18-2012, 10:11 AM	#3
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,891	I do a mod for lenses that do not have the switch, using a short price of pltic tubbing to block the pin in the depressed mode. The other option is to get an M42 adaptor that has a flange to depress the pin when mounted, although note these do not work with lenses made for the Spotmatic F or ES II which have a little bump on the bottom. (specifically SMC taks) If I find the photo I posted of the mod I will put a link here. Note the tube is about 1/8 inch ling (3 mm for the imperial impared) and I find the end of a ballpoint pen refil to be the perfect material

09-20-2012, 09:10 PM	#4
ckswong Forum Member Join Date: Apr 2012 Posts: 71 Original Poster	thanks guys, that was exactly what i was looking for. i was at work on my phone and google seemed to come up with nothing which was odd. but i also googled it at home and behold! all the answers lie there. thanks again.