What is the use of this switch on takumar 35 f2.3

tlerequiem · 04-03-2016, 09:34 AM

Hello Everyone,

I just got takumar 35 f2.3 but I curious that what is the use of the switch near the rear of the lens.

Thanks in advance

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edmundrt · 04-03-2016, 10:11 AM

It's for use on old screwmount SLRs. Auto-Takumars could be set up wide open for easier focusing, and when the shutter was fired the aperture would stop down. Unlike the later Super and SMC Takumars, the Auto versions do not reopen the iris automatically. This lever had to be pushed to manually reopen the aperture and prepare the lens for another shot. Of course, if you plan on using it with an adapter you'll need to keep the lever in the stopped down position. Hope this helps

**BigDave** · 04-03-2016, 07:56 PM

Originally posted by edmundrt

It's for use on old screwmount SLRs. Auto-Takumars could be set up wide open for easier focusing, and when the shutter was fired the aperture would stop down. Unlike the later Super and SMC Takumars, the Auto versions do not reopen the iris automatically. This lever had to be pushed to manually reopen the aperture and prepare the lens for another shot. Of course, if you plan on using it with an adapter you'll need to keep the lever in the stopped down position. Hope this helps

I have actually found these lenses quite useful when used with an Auto bellows for macro photography. Although a double cable release can be used, these manual stop-down aperture switches/levers allow you to PRE stop down the lens before taking the shot. This will reduce some of the camera shake and help keep the image sharp in extreme close-up macro applications

tlerequiem · 04-03-2016, 08:40 PM

Thanks Edmundrt and BigDave.

Very helpful. I didn't found any different on my k-01, perhaps, it is mirrorrless camera so stopped down is not necessary for k-01.

Just one question, which way is set to auto stop down (turn to left or turn to right)

Many thanks agian guys.

Last edited by tlerequiem; 04-04-2016 at 12:23 AM.

**Baard-Einar** · 04-04-2016, 04:16 AM

Originally posted by tlerequiem

Thanks Edmundrt and BigDave.

Very helpful. I didn't found any different on my k-01, perhaps, it is mirrorrless camera so stopped down is not necessary for k-01.

Just one question, which way is set to auto stop down (turn to left or turn to right)

Many thanks agian guys.

Hi

You cannot use it on DSLR with auto-function, that only works with the older m42 mounts. It needs a pressure plate inside the mirror house that presses a pin on the rear of the lens just prior to opening the shutter. this pressure plate was first seen on the Asahi Pentax K from 1958.

So to use it on modern cameras, you must manually twist the aperture ring to the desired f-stop, press green-button on the camera to get the proper exposure and then fire off the shutter.

When you move the handle to the left, you "cock" the automatic function. To release it without an older SLR with the mentioned pressure plate, you will manually need to remove the lens from the camera, locate the pin protuding from the rear ring of the lens and pushit. that should release the diaphrame.

Good luck! You'll love the really special creamy bokeh of this lens at f2.3

tlerequiem · 04-05-2016, 01:02 AM

Originally posted by Baard-Einar

Hi

You cannot use it on DSLR with auto-function, that only works with the older m42 mounts. It needs a pressure plate inside the mirror house that presses a pin on the rear of the lens just prior to opening the shutter. this pressure plate was first seen on the Asahi Pentax K from 1958.

So to use it on modern cameras, you must manually twist the aperture ring to the desired f-stop, press green-button on the camera to get the proper exposure and then fire off the shutter.

When you move the handle to the left, you "cock" the automatic function. To release it without an older SLR with the mentioned pressure plate, you will manually need to remove the lens from the camera, locate the pin protuding from the rear ring of the lens and pushit. that should release the diaphrame.

Good luck! You'll love the really special creamy bokeh of this lens at f2.3

Thanks guy. Yes I reaky love its bokeh.

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04-03-2016, 10:11 AM	#2
edmundrt Veteran Member Join Date: Jul 2014 Location: Nagoya Posts: 577	It's for use on old screwmount SLRs. Auto-Takumars could be set up wide open for easier focusing, and when the shutter was fired the aperture would stop down. Unlike the later Super and SMC Takumars, the Auto versions do not reopen the iris automatically. This lever had to be pushed to manually reopen the aperture and prepare the lens for another shot. Of course, if you plan on using it with an adapter you'll need to keep the lever in the stopped down position. Hope this helps

04-03-2016, 07:56 PM	#3
BigDave Site Supporter Join Date: Sep 2010 Location: Hudson Valley, NY Photos: Gallery \| Albums Posts: 2,626	Originally posted by edmundrt It's for use on old screwmount SLRs. Auto-Takumars could be set up wide open for easier focusing, and when the shutter was fired the aperture would stop down. Unlike the later Super and SMC Takumars, the Auto versions do not reopen the iris automatically. This lever had to be pushed to manually reopen the aperture and prepare the lens for another shot. Of course, if you plan on using it with an adapter you'll need to keep the lever in the stopped down position. Hope this helps I have actually found these lenses quite useful when used with an Auto bellows for macro photography. Although a double cable release can be used, these manual stop-down aperture switches/levers allow you to PRE stop down the lens before taking the shot. This will reduce some of the camera shake and help keep the image sharp in extreme close-up macro applications

04-03-2016, 08:40 PM	#4
tlerequiem New Member Join Date: Mar 2016 Posts: 3 Original Poster	Thanks Edmundrt and BigDave. Very helpful. I didn't found any different on my k-01, perhaps, it is mirrorrless camera so stopped down is not necessary for k-01. Just one question, which way is set to auto stop down (turn to left or turn to right) Many thanks agian guys. Last edited by tlerequiem; 04-04-2016 at 12:23 AM.

04-04-2016, 04:16 AM	#5
Baard-Einar Site Supporter Join Date: Jan 2010 Location: Oslo Photos: Gallery Posts: 964	Originally posted by tlerequiem Thanks Edmundrt and BigDave. Very helpful. I didn't found any different on my k-01, perhaps, it is mirrorrless camera so stopped down is not necessary for k-01. Just one question, which way is set to auto stop down (turn to left or turn to right) Many thanks agian guys. Hi You cannot use it on DSLR with auto-function, that only works with the older m42 mounts. It needs a pressure plate inside the mirror house that presses a pin on the rear of the lens just prior to opening the shutter. this pressure plate was first seen on the Asahi Pentax K from 1958. So to use it on modern cameras, you must manually twist the aperture ring to the desired f-stop, press green-button on the camera to get the proper exposure and then fire off the shutter. When you move the handle to the left, you "cock" the automatic function. To release it without an older SLR with the mentioned pressure plate, you will manually need to remove the lens from the camera, locate the pin protuding from the rear ring of the lens and pushit. that should release the diaphrame. Good luck! You'll love the really special creamy bokeh of this lens at f2.3

04-05-2016, 01:02 AM	#6
tlerequiem New Member Join Date: Mar 2016 Posts: 3 Original Poster	Originally posted by Baard-Einar Hi You cannot use it on DSLR with auto-function, that only works with the older m42 mounts. It needs a pressure plate inside the mirror house that presses a pin on the rear of the lens just prior to opening the shutter. this pressure plate was first seen on the Asahi Pentax K from 1958. So to use it on modern cameras, you must manually twist the aperture ring to the desired f-stop, press green-button on the camera to get the proper exposure and then fire off the shutter. When you move the handle to the left, you "cock" the automatic function. To release it without an older SLR with the mentioned pressure plate, you will manually need to remove the lens from the camera, locate the pin protuding from the rear ring of the lens and pushit. that should release the diaphrame. Good luck! You'll love the really special creamy bokeh of this lens at f2.3 Thanks guy. Yes I reaky love its bokeh.