Backing paper winding tool for 35mm film in medium format cameras

• 35mm film in the medium format camera: Expose 35mm film in your 6×4.5, 6×6, 6×7, or 6×9 camera – across the full height of the image window including the perforations for the typical sprocket-hole look.
• Original backing paper for correct frame counting: This tool wraps your 35mm film in the backing paper of an empty 120 roll – so the red backing window of your camera counts correctly, no more guessing the frame spacing.
• Prepare in daylight, spool in the dark: You align the film and backing paper in daylight; only the final spooling happens in a changing bag or darkroom.
• No special accessories needed: Works with standard empty 120 spools and used 120 backing paper that you already have.

Design & Idea

Based on a design by Simon (Simonp1080), published on Printables. We produce this tool with the explicit written permission of the designer – so you can use it even without your own printer. Many thanks, Simon!

Compatibility

• All medium format/120 roll film cameras: 6×4.5, 6×6, 6×7, and 6×9
• 35mm film (cartridge) – 24 exposures recommended; 36-exposure films may be too long
• Additionally required (not included): used 120 backing paper, empty 120 spools, a changing bag or darkroom, and non-permanent tape (e.g., Scotch tape)

Scope of delivery

• 1× backing paper winding tool, 2 parts: main body and locking clip
• Matte black, ready to use

Technical details

• Material: Technical plastic (PLA+), matte black – plant-based bioplastic
• Main body dimensions: approx. 148 × 72 × 30 mm
• Locking clip dimensions: approx. 82 × 25 × 15 mm
• Function: Transfers 120 backing paper onto 35mm film – makes it usable for medium format (120), including functioning frame counting
• Made in Würzburg, Germany

Description

With this tool, you wrap your 35mm film in the original backing paper of an empty 120 roll. The finished film then loads like a normal 120 roll film into any medium format camera – and because the backing paper runs along, the frame counter works normally. You align everything in daylight; only the final spooling takes place in the changing bag.

The result: 35mm film in a medium format body, exposed across the full height of the image window – with the characteristic perforation look and correct frame counting.

Frequently Asked Questions

• Why not just put 35mm film directly into the 120 camera? Without backing paper, the frame counter doesn’t work and you have to guess the frame spacing. This tool restores correct counting.
• What film length fits? 24 exposures are ideal. 36-exposure films may be too long.
• Do I get the sprocket-hole look? Yes. The 35mm film is exposed across the full height of the 120 window – the perforation holes are included in the image.
• What else do I need? Used 120 backing paper, empty 120 spools, a changing bag or darkroom, and non-permanent tape.