KO-140M 140mm F1.8 Projection Lens

 

KO-140M 140mm F1.8  Projection Lens

I'm a big fan of non-standard lenses, I try to shoot with any glass I find, regardless of its original purpose. So today I will show you a very interesting lens, which is definitely not made to be mounted on a camera, but I mounted it on a Nikon d80. 

KO-140M 140mm F1.8  Projection Lens

 KO-140M 140mm F1.8 is a projection lens. I know that it is a lens produced in the Soviet Union, but I do not know exactly what its history is and on what projector it was placed. I found it on a local sales site, it cost about $ 15. I am from Bulgaria and often old things from the Soviet Union can be found here, but such a lens is still rare, and the price was really good.

The first impression of the lens is that it is quite large. Everything is made of metal, even the caps that cover the lenses. 

KO-140M 140mm F1.8  Projection Lens metal caps

I expected it to be very heavy, but it's not really that heavy for that size. The metal from which the lens is made is hard but thin and also as far as I understand there are only two optical elements inside. It is just an empty tube with two magnifying glasses at the ends. Because the lens is not designed for photography, it has no aperture and no focus adjustment ring. Focusing was done through the projector, moving the lens closer or farther. I also think the lenses have no coating or there is quite pale. I am very glad that the lens came with caps. I've seen a lot of ads on really interesting optical devices but without caps and treated like rough things from the workshop. It is sad that in Bulgaria at the moment many super rare and interesting things from the past fall into the wrong hands. Here we have some old factories and warehouses, most abandoned after the advent of democracy (more than 30 years ago) and the right to private property. The new owners give everything to scrap in order to use the buildings

People from scrap companies are not very smart, they do not know what things they get. But some of them know that they are getting valuable things. They try to sell a lot of things online at high prices, but they don't know how to treat a lot of things, especially optics. I have seen many ads of lenses placed directly on the road on rough asphalt. And they want high prices for totally scratched lenses. These are lenses from various factory optical devices that can cost thousands of dollars. I've also seen people who have found a filming tape. Brand new movie tape unrecorded. And they opened the box to take pictures of what they were selling. In other words, they have illuminated the tape and it is no longer worth anything.

KO-140M 140mm F1.8  Projection Lens

In the beginning I wanted to buy KO-120M 120mm F1.8.  This is a slightly smaller lens - 120 mm, it seems to be a little more common than 140 mm. Ads often appear but are either quite expensive or are from these scrap companies and the lenses are in poor condition. I would say that the old Soviet optics are made solidly stable but not with high quality and precision. I have often seen small air bubbles in the glass of Soviet lenses. I have seen bubbles in helios 44, I have seen in Jupiter 8, and in this lens also on the front element there is such a defect. But this does not have much effect on the picture.

KO-140M 140mm F1.8  Projection Lens on Nikon

To be honest, I'm not quite done attaching the KO-140M to the camera yet. But I couldn't wait and took a few pictures. I mounted the lens on an aluminum rail on which it slides back and forth. At the end of the rail I drilled a hole and mounted the camera there. The camera is a Nikon d80, this is my favorite Nikon model. Yes, it is very old, its low light capabilities are terrible, but I love the colors it makes. When the back of the KO-140M touches the Nikon flange I have an infinity focus. I haven't made the connection between the camera and the lens yet, I just put a cap with a hole to limit the entry of dust and light. The problem is that if I make a connector between the lens and the camera, there will be more distance and I will not have infinity focus. Maybe in the future I will cut a small part of the back of the lens. In fact, the rear optical element is located inwards in the tube and it is not a problem to just cut a small part of the tube. This will allow me to make an adapter between the camera and the lens. Of course, if you use a mirrorless camera you will have no problems. Now focusing is a bit complicated, I slide the lens by hand on the aluminum rail, it's not very precise.

Anyway, let's talk about photos. I can say that without the aperture the KO-140M makes good sharpness in the center of the photos. But there is a lot of blur in the corners of the photo, especially when the subject you are focusing on is close to you.

KO-140M 140mm F1.8  Projection Lens sample photo

I do not consider this a defect, I even think it is an effect with which you can focus the viewer's attention on  your object or model . This means that the lens is interesting for portraits and situations in which you want a specific detail to stand out from the environment. 

The bokeh is not swirling, which surprised me. Because most old projection lenses are similar to Petzval lenses and they make a massive swirl. 

KO-140M 140mm F1.8  Projection Lens sample photo

As a problem with KO-140M I can say is chromatic aberration. In practice, you have no limit on how close to focus, you just need to make a system that allows the lens to move away from the camera, the farther the lens is, the closer you can get to the subject you want to capture. But the closer you focus, the more chromatic aberration appears. See the picture with the flower, it's not even chromatic aberration, but something like doubling the contours. If you take portraits, this may not be a big problem and this effect will be insignificant, but if you take flowers macro or in small detail, it will be quite noticeable. But in fact I like the blurred fog in the background that makes this lens. 

I still do not have enough experience with this lens and I can not be sure in my opinion, given that all the pictures I took have suffered some damage from the fact that light enters through the gap between the lens and the camera. But it is certainly an interesting experience to try and shoot with KO-140M.

     

Every project I do takes me time and materials, so if you like my projects please support me in Patreon- https://www.patreon.com/EdwardBlackRose . This will allow me to invest more in my projects. Thank you!