Instant Photography
Experiments with instant photography, primarily using Fuji Instax media.
Contents
Cameras
3D printed pinhole
Designed and 3D printed a custom Instax Mini format 3D camera.
Progress:
- v3 (in progress) use a commercially available pinhole shutter, improved light sealing with film holder
- v2 (current) uses 3D printed film holder to allow easy film swaps and processing
- v1 improved light sealing, tested multiple focal lenghts (23.2, 36.3, 50 mm - corresponding to 0.008", 0.010", and 0.013" pinholes)
- v0 initial prototype
Features:
- 1.25" filter threads (M28.5x0.6) for lens cap and telescope eyepiece filters (ND and color correcting)
- 1/4" Tripod boss for mounting (not yet added to current design, using a smartphone holder instead)
- 3D printed film holder
- Currently some light leaks. Need to improve sealing, maybe paint.
- Pinholes made in aluminum tape with precision end mills
- Need to measure
Adding custom lenses to existing Instax camera
3D print parts to mount manual lens (and focus/shutter as necessary) to a donor Instax camera. Using the donor camera will allow the film to be processed immediately without requiring transfers.
Progress: Disassembled donor camera, designing lens mount
Features:
- Need to decide on lens mount format
- ideally swappable with minimal printing
- Need to decide on power (~3v; 2x AA or 1 lithium cell)
- Planning to use a commercially available holder with either option)
- Also need to wire up film feed switch (momentary button)
- Design camera body (removed old shell during disassembly)
- hold film in body
- secondary light sealing
- cold-shoe
- tripod mount
- rangefinder/exposure meter
- Shutter cable mount
- Handle
Film
Transparencies
Modify Instax film stock to create image transparencies.
Existing work
All methods seem to involve manually scrubbing off the film layers (see Film Composition section below). This is time consuming, inconsistent, and can leave scratches or blank spots in the resulting image.
- Instax Manipulation: How To Make Transparency (Lomography)
- FUJI INSTAX TRANSPARENCY, be creative with INSTAX (Analog Things)
- /r/AnalogCommunity subreddit
Chemical Method
A chemical method that removes the unwanted layers without damaging the image is desirable to improve quality and repeatability.
Film Composition and Function
Instax film uses "Direct positive sigma crystal emulsion technology". The film layers are listed below from back (exposure side) to front (image side). See the last page of the datasheet for a diagram.
- Backing layer
- Magenta tinged clear plastic (daylight temperature correction?)
- Base
- Acid Polymer Layer
- Neutralizes processing fluid
- Neutralization timing layer
- Delays neutralization of processing layer until development is complete
- Processing Fluid
- Black paste stored in pouch, spread across image by rollers
- Alkali (potassium hydroxide)
- Opacifier (to block light during development)
- Other developer chemicals (possibly potassium thiosulfate and uracil)
- Easily washed away with water
- UV absorbing layer
- Development layers
- Three layers of light sensitive silver (halide) (blue, green, and red)
- Three layers of oppositely colored hydroquinone-decorated dyes (yellow, magenta, and cyan)
- Dyes paired with unexposed, developed silver halide transfer to the image receiving layer
- Intermediate layers between colors
- Light shielding layer (black)
- Light reflective layer (white)
- Opaque white pigment (titanium dioxide?)
- Image receiving layer
- Base
- Glossy surface backing layer
The primary layers that need to be removed are the development layers, the light shielding layer, and the light reflective layer. If the light reflective layer can be dissolved on its own, the other layers would also separate.
