Cosmicar 25mm 1.4: a rare bugger...

About 6 months ago I bought a silver, metal little lens. I had just discovered c-mount lenses and was lusting after unusual, old lenses(and preferably a combination of the 2). I found a Cosmicar 25mm 1.4 television lens on a Dutch website for secondhand articles and I bought it for around €80,-
Now recently I've been working on a little project and I've been using this Cosmicar lens in combination with the GH2. It's sharp, colors are nicely saturated but there's some heavy vignetting when stopping this lens down so I have been trying to find out what thread size I need for a ND filter. Turns out that's one tough piece of information to come by..! These lenses are very rare.
Cosmicar has been taken over by Pentax and the new Pentax 25mm 1.4 is a different lens altogether and has different measurements. I found one picture of the exact same lens as mine on Flickr but that account has been inactive for 2 years... Otherwise... nothing on the web. So I contacted Pentax Holland, who referred me to Pentax England. I filled in an online contact form and was called up by Pentax Belgium! Who took my question to Pentax Germany. Pentax Germany told me they weren't sure but the lens was probably from '69. They did not have any records of sizes and advised me to measure the lens diameter by hand. My best bet was 34mm. A stepup ring is on the way.

VERY SMOOTH APERTURE AND FOCUS RING

LOOKS MODERN BUT THIS LENS IS OVER 40 YEARS OLD...

Return of the 15,- Pentax 6mm 1.2 (a succes story!)

grind down more on the side, as shown in picture

Ever since I bought my Pentax 6mm 1.2 cctv lens, I have not been able to focus on infinity. I paid someone €20,- to shave down the rear barrel of my lens but to no avail. I started grinding my c-mount adapter but that was not succesful either.
The problem is -and I know other buyers are struggling with the same thing- is that you don't know exactly how much to grind down of the barrel. People didn't get it and I didn't, either... It's not that the person who 'discovered' this cheap wide and fast lens, Seb Farges, wasn't helpful. He shared pictures of the mod but he was not able to explain exactly why simple 'shaving off a few millimeters' didn't work. But then, upon close examination and with the help of blogger Obakesan I finally noticed what I was supposed to do: shave off the outer side of the barrel a few millimeters more, untill you reach the screw on the side.
I bought a €35,- Dremel (electric tool) to do the job and after a few rounds grinding down the barrel... tadaaaa! Infinity! I am infinitely happy with the results... I will post some footage I shot with the Pentax soon. (Note: this is not a dirtcheap lens anymore: 15,- for the Pentax, 2 c-mount adapters@ 19,- together, 35,- for the Dremel... But the Dremel is a lovely tool: I used it to slice through metal today and it lived up to the task!)

GH2 AND PENTAX 6MM 1.2: TOGETHER AT LAST!

This is the drill for my 15,- Pentax 6mm 1.2

THE DREMEL: IF THIS DOESN'T WORK, NOTHING WILL...

I cannot get my Pentax 6mm 1.2 c-mount lens to focus on my Panasonic GH2. I am stuck with a fixed focus lens while others have been able to shoot good stuff with this wide-angle, fast lens I bought for €15,-
I am going to give this lens one last shot and bought a Dremel (mini-drill) that will help me modify my lens even further. I have instructions from people that have been succesful at getting infinity focus with comparable lenses... Either I'm going to shoot some lowlight, wide angle stuff pretty soon or I'll be stuck with a handfull of scrapmetal...

PRECISE INSTRUCTIONS FOR MODIFICATION

Mailbox: television lens, Cosmicar 25mm 1.4

I'm going a little nuts with the lens business. A buying frenzy has taken possesion of me but I promise this is the last one in this series of C-mount 16mm lenses. (there's just 2 more coming from the States- a birthday present from my wife! although she doens't know it yet...)
This Cosmicar-for-Bolex lens is a 25mm 1.4 version and in absolute pristine condition. It produces this wild, swirly bokeh. Can't wait to shoot video with it on my GH2.

Mailbox: is there a lens in this envelope?

I bought a 25mm f1.2 CCTV lens for 35 euro's and when I had to sign for an envelope, the last thing I thought was in there was a lens! This thing is so small and yet so light sensitive- how do they do that? It came with an adapter plus an adapter-for-the-adapter?! I tried mounting it with the two adapters but it wouldn't focus. When I just used the big adapter ring, it worked. The focus ring has no stop for infinity so you can just turn it around infinitely(!). On the aperture ring it just says 'open' and 'close' and there is a hard stop on both ends.
Vignetting is obvious when you open the lens up and disappears in crop mode on the GH2. I think for such a toy lens it produces nice images. Here's a few test shots I made. I'll try to post some night shots as well.



25mm 1.2 CCTV lens from Filmersblog on Vimeo.