Front view of a Pentacon auto 50mm 1.8 lens
Pentacon 50mm 1.8

Focal Lenght: 50mm
Max Apeture: 1.8
Lens Mount: M42
Min. Focus: 0.33 mm
Filter Size: 49mm
Weight: 190 gr of iron
A/M switch


As my interest in old, vintage or whatever you’d call them lenses grew, I started reading more and more on the topic. I read and read and learned some of them might come with a range of different problems. It might be a stiff focus ring or a stuck aperture. I read about people who could solve these issues and excited, went online to search for one near me. 

Now, I’m not from a big country. I live in the second largest city around. I looked for camera/lens repairmen and technicians, but found scarce information. Most were either retired or had passed away. The few left had backlogs of several months due to high demand. Luckily one of them was in the same city as me. I called him, excited to learn about such an interesting person. He was very pleasant and had a lot of experience, but aged over 80, couldn’t work on lenses anymore. 

I felt sad and miserable for a while. I wanted a teacher, I wanted to be an apprentice, but that seemed far out of reach. Deciding that that mindset doesn’t do much, I thought I’d learn with the resources I had. One of my hobbies is origami, so if I can create a model with 300+ modular pieces, I could most likely learn with enough time, patience and effort. (I am a bit obsessive and stubborn, so that helps now and then.)

I found this lens online for a measly price (3 coffees) and it’s aperture was stuck. 

When I got my hands on it and looked for materials online I decided to have a go at it. Man apertures are frustrated to but back together. After a night of no sleep (I guess I was stubborn), I had the aperture fixed. But in my inexperience I had separated the focusing helicoid – something that’s sort of hard to put back together. (unless you’re smart and have market where the the thread screws in) I struggled for a few days with it and left it, now a pseudo-macro lens. 

I tried to fix it on and off, but trial and error dissasembly frustrated me to no end, I associated this lens with my own failure.  As a few years passed I had relubed a few focusing helicoids succesfully and figured out the underlying and common principles that united some of them.  I decided I’d give it a go. So in about 2 hours, I managed to fix my past mistakes and decided to spend time shooting with it.


The lens handles well, I appreciate the common filter thread, the metal build and it’s close focus capabilities.
The A/M switch is always nice to have, in case your adapter can’t depress the auto-aperture pin.

Although there is nothing extraordinary in it’s handling, that’s not a bad thing. There really isn’t that much to rediscover in the proverbial 50mm wheel.

I loved the close focus capabilities and spent a lot of time playing around with that, as you can see, photographic leaves and small detailed pieces.


It performs as you’d expect, soft wide open, with some shaprness in the center. Some spherical aberration veil your images when shooting wide open. There is a hint of barrel distortion. Contrast is okay wide open, so not much to say there. 

Stopping by to 4 or 5.6 improves performance a tad. By 5.6 corners start catching up and improve drastically to what you had before. They never reach the sharpness you see in the center, but get good enough

Contrast is reduced wide open and benefits a lot from stopping down.

Colors are more on the neutral side, maybe slightly on the cooler side and I personally like them a lot.

Bokeh was a bit sharp and frantic at times, so make sure to lookout for that. In close ups I found that slight defocus worked a lot better than using it as a regular macro lens and going all in on that bokeh. Trees in the background usually became a zig zagging tangled web of madness I didn’t fancy that much.

Taking the price into consideration, that’s good enough. 


This isn’t an expensive lens and It’s not a high-end lens. You can most likely find a copy reather easily. It does what it can for the price and it does it well. Keep a lookout for stuck focus rings or apertures, both seem to be common problems if the lens hasn’t been serviced.

I would recommend this as a “first dip” in the ocean of manual focus lenses. You wouldn’t have invested that much and with so many copies around, you’ll have an easy time finding one.