OKTO35: A Genius Invention for Making Movies on Regular 35mm Film

10 min read by Dmitri.
Published on November 11, 2025.

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OKTO35 is a new motion picture camera capable of shooting 25% larger frames than Super 8 at up to 25 frames per second on any standard 35mm (135) film cartridge.

Shooting movies on OKTO35 can be 80% cheaper than on Super 8. Better yet, it can shoot ultra-high-resolution films like the Adox CMS 20 II, infrared films (like Aerochrome), orthochromatic films, films without remjet, and everything else that comes in a standard 35mm film cartridge.

A single 36exp. 35mm film roll will fit ~1,150 frames on four tracks, which is about 50s at 24fps or 2min at 10fps.

OKTO35 exposes 4 tracks on a single roll of 35mm film.

This is an ongoing project with several prototypes and fascinating engineering behind it. In this article, I’ll review what I’ve learned after talking to the camera inventor, Blaž Semprimožnik (see his website), explore the camera’s design and features, and share the production plans for OKTO35 (i.e., when it may be available for sale and how much it might cost).

This post includes several exclusive samples, excerpts from my three interviews with the OKTO35 inventor, and my recollection of inverting and colour-correcting raw footage.

Watch out for a podcast interview with Blaž!

In this article: The state of photochemical filmmaking in 2026. A brief history of the OKTO35 project. Scanning, editing, and converting raw OKTO35 footage. The future of the OKTO35 project. Support this blog & get premium features with GOLD memberships!

The state of photochemical filmmaking in 2026.

Whether you wanna shoot Super 8, 16mm film, or movie-theatre-worthy films on 35mm+, your footage will be very expensive compared to what you’d get from digital cameras. Film directors justify those costs with savings from taping fewer takes and simpler editing workflows; however, I’m approaching this from a personal or very small production budget perspective.

That shouldn’t be a surprise, given that still photography on film isn’t typically cheap — multiply that by the video framerate, which can mean up to 1,500 exposures per minute, add the complexities of developing and scanning, and you’ll get a price that’s significantly more than just the film alone.

8mm film is the cheapest way to produce motion pictures on film — but it comes with its downsides. It’s very grainy, as the width of each frame is much smaller than that of even the smallest still camera format, 110. There are limited options when it comes to film stocks, and home development/scanning is impractical; thus, you’d have to pay someone to do that work.

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Footage shot and scanned with OKTO35.

The 16mm motion picture format delivers more resolution — but at a price. Not only do you have to pay more for the stock and development, but the cameras themselves are often more expensive as well.

35mm formats and above are even more expensive, with costs swelling up to millions of dollars for large productions like Oppenheimer.

The idea of using standard 35mm film that comes in 135-format cartridges to shoot short clips isn’t new. Lomography introduced LomoKino over a decade ago, which exposed short clips on standard still camera film. However, that product has left the scanning process and the quality of film transport unresolved (I will be reviewing my experience with that camera in a later post).

As 3D printers made home engineering easier, a few new products surfaced over the years attempting to replicate and improve what LomoKino has offered. OKTO35 is the most comprehensive solution to date, designed and built by Blaž Semprimožnik in his home.

OKTO35 Mk1.

A brief history of the OKTO35 project.

Blaž started thinking about making his own movie camera sometime in 2019 after realizing that Super 8 filmmaking was beyond his budget. As an engineer by profession, he figured he could make a camera using 3D-printed parts and his own assembly of electronic components.

He was right that he could. His first prototype, OKTO35 Mk1, was a shoebox-sized contraption with a film transport powered by a single pulldown claw controlled via Arduino Mini. It had a 7-segment LCD display and could shoot at 12–16fps with a fixed 150° shutter angle¹.

But even in its rudimentary form, the camera could expose four tracks on a single roll of 35mm film and could be synchronized with a DSLR to function as a film holder with automatic transport for scanning at home. These two features made OKTO35 incredibly affordable by allowing the operator to use readily available film stock and take the entire production — from development to scanning — home.

OKTO35 Mk2.

OKTO35 Mk2 was a refinement of the first prototype. It supported interchangeable C-mount lens support, it could shoot at 10–24fps at a fixed 160° shutter angle¹, and even create time-lapse scenes with 1-6 second delays between each frame. It had a built-in center-weighted light meter (which supports 50–3200 ISO films), connected to the LCD. There was also a timed-delay trigger, shooting time indicators, an improved body design, and a built-in battery — all powered by the STM32 processor.

Mk2 was a significant step forward — but Blaž wasn’t done, as he immediately began working on Mk3 based on what he’s learned from his previous experiments.

One of the most challenging things in camera design is the focus system, which, for OKTO35, had so far involved looking directly through the film (which made the view very dark). Mk2 would solve it with a through-the-lens optical finder and ground glass. Mk2 will also have an auxiliary finder with an OLED display.

Another substantial update would be the dual-gate exposure sizes: 4:3 (6.3mm × 4.7mm) and 16:9 (8.4mm × 4.7mm) — the latter should produce three tracks but increase resolution, approaching what you’d get from a 16mm film format. Plus, the framerate would be adjustable up to 25fps.

Mk3 designs also feature support for physically larger C-mount lenses, a more precise frame advance system (for reduced gate weave), reduced light leaks between the tracks, noise reduction, and USB-C battery charging (with a user-replaceable 18650).

Last but not least, Mk3 may implement an external film magazine system that lets you place your bulk roll to increase the number of frames up to 20 times! Plus, an electronically variable shutter angle¹ that can be set between 90° and 180°.

¹ — A shutter angle in motion picture cameras refers to the shutter speed relative to the video framerate. A 360° “full” shutter angle means the shutter opens at the same speed as the film advances (so a 24fps video will have a shutter speed of 1/24s, whereas a 10fps video will have a shutter speed of 1/10s). Smaller shutter angles relatively increase the shutter speeds; thus, a 180° is 1/48s at 24fps, and a 90° is 1/96s at 24fps. Consequently, a 160° angle at 24fps is 1 / (160° / 360° × 24fps) ≅ 1/10s.

OKTO35 Mk2.

Scanning, editing, and converting raw OKTO35 footage.

Though Blaž is the only person in the world with the OKTO35 on hand, he did send me some raw scan footage to play with.

Blaž warned me that the backlight he used doesn’t have great CRI ratings, yet it was all scanned with OKTO35 sync and his digital camera.

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Raw film footage from OKTO35.

The raw colour-negative footage is, as you’d expect, not watchable. It’s upside down, the colours aren’t there, and it’s very shaky. But all of that can be fixed.

Luckily, DaVinci Resolve is free, which, after a slight learning curve, makes the job fairly easy. I used the Invert Color effect and the histogram stretching principle in the Color > Curves view to invert the negative. It also makes stabilizing the footage (very easy via the Edit view under the Inspector > Stabilize — I used Similarity with “Camera Lock” checked).

Then, I played with the Curves some more to get the contrast and colour balance for each channel so they matched my expectations for this film (Kodak Gold) and then exported the footage using the Apple ProRes 422 HQ preset.

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Footage shot and scanned with OKTO35.

The results, of course, aren’t the pinnacle of what this camera is capable of. Finer-grained film, higher-CRI scanning backlight, and several more tools can be used to get higher-quality images.

Additionally, I used FFmpeg to convert the footage into animated GIFs, which you see here. Serving this type of content is very expensive for me, so all the files had to be no more than 10MB — whereas the raw clips were about 100MB each.

FFmpeg settings for converting videos to GIFs.

I used variable resolutions for the clips in this article. 320px (width) was for videos that don’t fill the entire screen on a laptop/tablet. These clips could be a little longer.

The full-screen videos (including the one at the very top of this article) had to be shorter in length but denser pixel-wise — I used 800px for the poster and 700px for the clip above.

Naturally, converting Apple ProRes videos into smaller GIFs with limited colour palettes reduced their resolution, yet those reductions are not very visually significant. The original format is already much smaller than that of a full-frame still camera. The good news is that the drop in spatial resolution (pixel count) is made up for with the involved motion (increased temporal resolution).

The future of the OKTO35 project.

As I’m working on this article, Blaž is finishing up his Mk3 prototype, which he says should be ready for third-party testing (I might get my hands on the pre-production model — watch this space).

The final prototype is expected to be complete by the end of 2025 or in early 2026.

Though the above models aren’t meant for full-fledged production, Blaž hopes to eventually start manufacturing his camera. One possible source of funding for this would be a collaboration with a local Slovenian film digitization lab. You can also support his R&D directly via donations (either via PayPal or by arranging to send Blaž some film via Gmail).

Right now, it takes at least 1.5 days to just print the parts and several hours to assemble the components. However, Blaž aims to sell OCTO35 for under $1,000 once he fleshes out the fabrication and assembly.

Make sure to subscribe to Blaž’s YouTube and Instagram to follow his updates!