Spotmatic F

I recently acquired a Pentax Spotmatic F in very good condition. The camera came with no batteries, so I tried using an LR44 battery that was sitting inside my Pentax K1000. The LR44 seemed to work fine, in that it activated the meter, but keep in mind that the LR44 is rated at 1.5 voltage while the Spotmatic F was meant to run on an PX625 Mercury battery rated at 1.35 voltage.

 

Like i said, the meter on my Spotmatic F seemed to work fine with the LR44 battery, but it wasn't until I inserted a WeinCell MRB625 Replacement Battery for PX625 that I got from Amazon, that the meter suddenly came to life and became way more responsive ?

 

The reason I purchased the Spotmatic F in the first place, was that I wanted to use some of my legacy Takumar lenses that I have accumulated in the last recent years without using an M42 adapter. I have so far used those lenses on my K-5 IIs digital camera, using a Pentax adapter. That worked fine for a while, but now I want to experience using the SMC Takumar lenses the way they were supposed to be experienced. !

 

Currently I have 5 SMC Takumar lenses. The 24mm f3.5, the 28mm f3.5, 35mm f3.5, 50mm f1.4 and the 135mm f2.5. All I'm missing is the renowned 85mm f1.8, which I hopefully will be purchasing in the coming weeks, if everything works out OK ??

 

I will probably be shooting mainly B&W. After this harrowing and extremely complicated year, I want to return to something much more simpler. My darkroom is set up for B&W, but I might also get into some color. Wish me luck !

Edited December 24, 2020 by hjoseph7

The Spotmatic meter circuit has a bridge rectifier set up so I believe variations in battery voltage should not be a problem. I've actually used an alkaline 626 in my Spotmatic F with good results.

What Mike said!

but there are several good reasons to avoid alkaline batteries to feed meters in cameras.

The discharge curve is less desirable which may account for OPs experience with the LR44 battery. And they simply have a higher tendency to leak over Silver Oxide (like SR44) or Lithium.

If available, the preferable type is Lithium, as it also have an extremely long shelf-life, and I have yet to experience one leaking.

I understand that many of the later Prakticas with meters, etc., also have bridge circuits. (Thanks SP)