How to use Auto Takumar 55/2 on SP500

[daniirwan]

Hi all! I was given my first ever M42 lens, and also my first ever Takumar, by a
friend from down under recently. It is an Auto Takumar 55/2. Now, I intend to
use it on my SP500 which I don't have any lenses for, until now that is =)The
lens itself is pretty beat up, there's fungus in it and some not so slight wear
on the barrel. The aperture ring seems tight but there's no oil on the blades,
and it stops down correctly so that's good. It looks similar to the lens in this
photo:

http://www.pbase.com/gummiebear/image/43419949

Thing is, I'm totally clueless as to how one should use this lens with the
Spotmatic. I read somewhere that this lens is a type of preset lens, and it is
'auto stop down, manual open up'. I don't really understand that, forgive
me..since this is my first foray into m42 lenses and also 'automatic' lenses, I
hope u understand. There's a sort of switch (A/M switch) on the lens barrel
which I can rotate, when I do, the lens aperture opens up completely regardless
of the fstop i selected on the ring. When I depress the pin on the inside flange
of the lens, it stops down to the selected aperture.

Now, how do I use this lens with regards to the stop down metering switch on the
SP500 body? What does it mean by auto? By auto, does it mean that the camera
will automatically stop down the lens when I press the shutter? When should I
rotate the A/M switch, before or after engaging the meter switch on the SP500
body?

I'd appreciate any help I can get. Thanks in advance!

[WolverineX]

try to find your answers at this site

http://www.photoethnography.com/ClassicCameras/index-frameset.html?AsahiPentaxSP500.html~mainFrame

regarding auto and manual settings on m42 lens. if you set it to manual then when you move aperture ring you set aperture blades to desired setting and they stay there ("stopped down"), if you set it to automatic blades stay fully open regardless of chosen aperture until you press a pin at the back of the lens (where the mount is) , film camera presses that pin when you push shutter release button to take a photo

[Nesster]

Yours is the preset version of the auto-tak, and I envy you

On the spotmatic, sp500 included, you push up on the meter switch with your right hand finger to turn the meter on. With 'auto' aperture lenes, i.e. ones that have a pin in the mount, turning on the meter also pushes the pin in and thus closes the aperture, for metering.

Since yours doesn't have the pin, when you turn on the meter you also need to stop down the lens using the thing near the top of the lens... then it's a matter of putting the needle in the view finder inside the target zone. You do this the usual way -change aperture and/or shutter speed.

If the lens were an 'auto' then you'd still set exposure the same way, just omit the stop down bit on the lens.

The assumption is you don't need to or want to meter every shot. So I'll next describe the normal shooting sequence... once you've set exposure.

With an 'auto' lens, when the pin in the mount isn't pushed in the lens remains wide open. So you can focus and compose with as much light as possible. At the moment you trip the shutter, the camera pushes the pin in, stopping the lens down to taking aperture, and then releases the pin to return the lens back to wide open. Hence 'auto'.

With a 'preset' lens, you use the preset mechanism to do what the 'auto' does, only by hand. That's what the knob on your auto-takumar is for. Other preset lenses may have two aperture rings - one to set the taking aperture, and the other that moves freely between that stop and wide open. So, if you choose to, you can flip the lens to open in order to focus and compose, and then use your finger to flip it to shooting aperture before you trip the shutter. Then repeat - flip the lens open, flip it back closed again to shoot. Sounds like a pain (and it is) but considering there are no digital cameras that can manage an 'auto' pin on a M42 lens... it's digital ready

My auto-takumar 55 /1.8 has the auto pin in the mount and an 'auto/manual' switch. The earlier version of this lens - like the one in the pbase sample - is a preset type. These are really good lenses, I really like the rendition of these simpler-coated ones.

Oh damn I needed to read what you wrote more carefully. Yours is not a preset if it has the pin. Just set the switch to auto and it behaves like the 'auto' lens I describe above.

[daniirwan]

Nesster & Wolverine: Thanks for your inputs! I highly appreciate it...now I understand a bit more on how this lens work. I've just sent it for a CLA last week and it should come back soon...hope the fungus will be gone by then and the A/M switch is ok