Aperture Mechanism Takumar 50/1.4

[Mackinaw]

A friend of mine recently gave me an old Pentax Spotmatic II with the 50mm F1.4 super-multi-coated Takumar. The camera works beautifully but I noticed that the lens is a little balky when reopening to F1.4 (it stops down to the set aperture with no problem, but reopens slowly to full aperture). Are there any tricks to opening up a 50/1.4 Takumar I should know about? I'd like to clean out the stop-down mechanism so the lens opens and closes normally. Thanks.

Jim B.

 

[titrisol]

Start by exercising the diaphragm a few hundred times.
Just push the pin at f/22 and allow it to come back.
Check if there is any grease in the blades.

This may help of you decide to go all the way!
http://www.mypentax.com/tak50_1_4.html

A friend of mine recently gave me an old Pentax Spotmatic II with the 50mm F1.4 super-multi-coated Takumar. The camera works beautifully but I noticed that the lens is a little balky when reopening to F1.4 (it stops down to the set aperture with no problem, but reopens slowly to full aperture). Are there any tricks to opening up a 50/1.4 Takumar I should know about? I'd like to clean out the stop-down mechanism so the lens opens and closes normally. Thanks.

Jim B.