The 1/8th Frame Format

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[The 1/8th Frame Format]

In the same vein as the previous two articles: Ultra Half Frame and Methods for Dividing Photographic Film. This is a 2nd “new” film format specification based on longitudinal and half frame splitting principals. This format is inspired by the Fujifilm Byu-N 16, it is a half-half-half (H3) frame format which produces 8 exposures on one frame of 35mm film. Unlike that Fuji camera’s format which is primarily intended to capture animated sequences, this format is specifically intended for individual stills in a regular single lens camera body.

Exposures should be approximately 8.5mm and no larger than 9mm in width with a ~0.5mm gap between each exposure for a bespoke camera which is designed for this format, OR a ~0.66mm gap for camera’s which must follow traditional 35mm film transport movements (~2mm space between full frames). The height of the exposure is ~>11mm with a ~2-1mm gap between rows. Alternatively a movement could be designed which simply uses two perforations to determine frame spacing, this would reduce mechanical complexities but also greatly increase the space between frames thus reducing film economy.

Final images are intended to be cropped to the typical 3:4 “portrait” format of a half frame photo and viewfinders should be 3:4 format allowing for slight misalignment with the actual exposures. 1/8th Frame exposures are permitted to overshoot the typical vertical area of a full frame (going closer to sprocket holes), typically for flexibility in viewfinder alignment. The exposed area is intended to be flexible so camera designers are not limited by the format. While the core concept is to fit 8 individual exposures in the approximate area of a typical full frame, truly the size of the exposure on 35mm film is what makes the format unique not necessarily the frame spacing or density.

Compared to other small film formats, 1/8th Frame has significant benefits. 1/8th Frame is slightly larger and vastly more practical than disk film format. Exposures are also very similar to Minox 8x11cameras without needing exotic 9.2mm film. 1/8th Frame exposures are larger than standard 16mm motion picture film(10.2x7.5mm) and only ever so slightly smaller in one dimension (but larger in the other) than super and ultra 16mm(12.5x7.4mm and 11.66x6.15mm respectively). The 1/8th Frame format is very similar to but slightly smaller than a 1” format digital sensor (12.8x9.6mm).

Compared to the 110 film format 1/8th Frame is far more functional. 1/8th exposures are ~4.5x6mm smaller but provide over 10X the amount of exposures per roll of 110 film. The 1/8th Frame format uses standard 35mm film which is much more cost effective and readily available with many more options than 110 film. 35mm film is also far easier to process and handle than 110 film. There is also no vendor lock with 1/8th like there is with 110 (Lomography is the only company that makes 110 film).

Metering is also easier since DX codes can be utilized. While the 1/8th Frame format is intended to maximize film economy and provide and equivalent image size of a 16mm motion picture still it actually excels at doing what the 110 format’s goal was in the first place, which was providing a cost effective consumer film format that people will enjoy shooting.

Using this format allows at least 288 photos to be shot on a typical 36 exposure roll of 35mm film. I say at least because a custom camera that shoots this format could be designed to ignore typical sprocket hole based frame spacing which on a 36 exposure roll will add up to nearly 2 additional full frames of film area. This would of course require complete complex control of the film movement.

Another bonus from a camera built for this format is that it would also not require nearly as much film leader to be removed from the 35mm cassette during loading, thus granting you at least one additional full frame of exposure area. Of course one downside to this is that the typical photography lab is not equipped to scan these types of non standard formats due to their lack of technological progress.

Another benefit to the 1/8th Frame format is lens choice. The image circle required to cover the format is very small, equivalent to regularly available 16mm motion picture lenses. This small image circle allows a huge number of existing lenses to be used and makes designing custom lenses for the format significantly easier. Like modern non detachable lens 1” sensor point and shoot cameras, a custom made 1/8th Frame format camera can fit complex lens systems in a very small area.

A downside to the 1/8th Frame format is that optical centering is significantly more important than other longitudinally split formats like Ultra Half Frame. A 1/8th Frame camera would likely be required to use a moving film transport or moving optical system to facilitate the longitudinal split. Compactness is a goal of the 1/8th Frame format but cameras will still be limited by the 35mm cassette size, however this should not discourage the creation of pocketable compact camera systems.

Below is an example of the quality of 1/8th Frame. This is actually a photo taken from a Minolta 110 zoom mk2 with Lomography Tiger 200, but cropped to match the approximate size of a 1/8th Frame format exposure. I used 110 for this example due to the close size similarity, but modern 1/8th Frame format cameras should regularly surpass this image quality via optics and film choice.