c-mount lenses for the BMPCC

Ever since I saw the Ikonoskop A-Cam DII at the IBC show floor with some small and beautiful c-mount lenses I was in love. I never had a 16mm film camera and had never really seen these kind of lenses before, but was imediately fascinated by them mostly because of their 'cute' appearance.

I owned a Nikon D7000 at that time so it didn't make any sense to buy 16mm format lenses but my interest was triggered and ever since I have been looking to see if I could justify buying a camera that did have a purpose for these lovely lenses.

I regularly checked the website of a vintage camera store called 'Fotohandel Delfshaven' (they have a english website as well where they operate under the name: MKOptics) to see what 16/S16 c-mount lenses they had available.

So when I decided to buy a Blackmagic Pocket Cinema Camera I immediately ordered a c-mount to MFT lens mount adapter to be able to use those tiny c-mount lenses on my pocket camera.

A week after I got my BMPCC I went to Rotterdam to check out the store and their (c-mount) lenses in person. I had never been to that part (Delfshaven) of Rotterdam before, it's one of the parts of Rotterdam that hasn't been bombed in the second World War and thus is still really authentic and in my opinion very beautiful, here is a photo I took with my iPhone 5:

Delfshaven, Rotterdam

When I walked into the (small) store it was like walking into a candy store as a kid, so many things to look at: vintage lenses of all kinds, photo camera's, movie camera's, just too much stuff I wanted to to try out :-) I definitely recommend going there if you are in the area.

Before I went to Rotterdam I obviously had checked on the internet what kind of lenses I wanted. I was hoping to find a good wide angle lens, because of the 3x crop factor on the S16 sized camera my widest lens is my Nikon 17-35mm F2.8 which has the same FOV as a 51-105mm on my Nikon D800 (Full Frame) camera.

I had seen some footage on Vimeo of a BMPCC with a Schneider Cinegon 10mm 1.8 lens that looked really nice and sharp, so I definitey wanted to try out this lens because the store also had a Schneider Cinegon 10mm 1.8 lens listed on their website.

I had brought my BMPCC to the store and the guy who owns the place let me try out some nice lenses starting with the Schneider Cinegon 10mm F1.8: when I screwed it on I noticed that it vignetted in the corners of the image. Clearly this was a different version of the lens that I had seen on vimeo, so that was a bit of a bummer. But despite the vignetting kind of liked the image I saw on the back of my camera, it did have a nostalgic look to it that I liked very much.

I tried out some more c-mount lenses but they all vignetted except the Schneider Kreuznach Xenoplan 25mm 1.9 lens that I tried:

Schneider Kreuznach Xenoplan 25mm 1.9 c-mount lens

A more modern c-mount lens but absolutely too beautifull to not take with me for the 75 euro I had to pay for it.

A little in doubt what I should do with the Schneider Kreuznach Cinegon 10mm lens I decided that it was at least the best wide option available for me at the moment so I bought it for 100 euro:

Schneider Kreuznach Cinegon 10mm F1.8 c-mount lens

Step-up Rings for c-mount lenses?

I also wanted some step-up rings for the lenses I bought, so I could put a variable ND filter on them and shoot with a more open aperture during the day. Unfortunately they didn't sell those a the store so I went to the largest camera store in Rotterdam to see if they did, but they also didn't...

Turns out that it's not that easy to get a step-up rings for these lenses, when back home I googled to see if I could find what filter thread the lenses had but with no luck. I guessed (after using a ruler) what kind of diameter the filter thread was and decided to order a 31.5mm -> 37mm step-up ring with a 0.5mm thread pitch and a 31mm -> 37mm step-up ring with a 0.5mm thread pitch from Camera-Filters.com but they both didn't fit on any of the lenses.

So this can be a real problem when buyin these lenses, you already have less shallow depth of field to play with because of the sensor size, and now the shallow depth of field that you have left will be dimished by the fact that you have to stop down to be able to get the right exposure.

Shooting with the c-mount lenses

When I got back home it was already getting dark, so shooting without a variable ND wasn't going to be a problem :-) I had diner at my sisters place with my dad and my nephew and went to visit an ex-colleague of mine later that evening, at both occassions I shot some footage. Later that weekend I went to the centre of Uitgeest, the city where I live to shoot some scenes and I also took it to work and my dad's place later that week when the RAW update was released by Blacmagic (but more on that in a later blogpost)

Here is a compilation of those clips that I shot:

The beautiful music was bought from iTunes and is called 'Passaggio' by Luduvico Einaudi.

Lenses used in which shots:

Only the first shot is taken with the Xenoplan 25mm 1.9, the rest with the Cinegon 10mm 1.8 except at 0:51 and 1:00, those are taken with my Nikon 17-35mm 2.8

You can see some vignetting in the video, I mostly tried to get rid of it by creating a 2.35 aspect ratio timeline (1920x816 pixels) but couldn't avoid it entirely.

What it was like shooting with the c-mount lenses

What I really liked about this minimal setup is that I could literaly fit it into the pocket of my wintercoat. Tiny camera, tiny lens, beautiful image. This is why I bought this camera! It also fits into the front pocket of my backpack, this is really something else opposed to a Nikon D800 DSLR.

But it's use in this way is ofcourse somewhat limited, with the 10mm Cinegon lens it is possible to shoot handheld, with the 25mm Xenoplan not so much (more about this in a later blogpost). When it's a sunny day there is no way you can get exposure with the 10mm Cinegon lens, when stopped down completely the vignetting becomes worse and in my case you will see some spots that are on the lens and as said earlier it will be really hard to get a variable ND on this lens.

Having said that, the image out of this camera with this lens in the right circumstance is just lovely, the extra dynamic range you get really makes a huge difference, it seems to give the image more soul.

But let me reiterate: the idea of having this camera with these nice lenses is somewhat more romantic then reality, it's use with these kind of lenses is pretty limited, so keep that in mind if you a considering to buy a Blackmagic Pocket Cinema Camera for the same reasons I have bought it.

Grading for the compilation

All shots were graded in Resolve using Captain Hook's LUT as a starting point. I then tweaked each clip to my liking and then exported all the clips to PreRes and edited it in FCPX.

[Update: The original video was placed on a 1920x1080 timeline with the letterbox filter to get that 2.35 aspect ratio, but was later rendered with Final Cut Pro 10.1 on a 1920x816 timeline, because now it is possible to have custom sizes in your project.]