Infra-red

Recipe:

Kodak HIE 35mm - infra-red film (sensitive to 900nm)
Load (and unload) in total darkness
Wratten 25 (red) filter
ISO 400
Meter through the lens (i.e. NOT with a separate handmeter)
Bracket: +2 stops and -2 stops (infra-red is unpredictable)

Develop for 11mins in neat (undiluted) D76 at 20c (agitate normally)
Stop and Fix as usual
Print on Grade 4 or 5 paper


This is a starting point for your own experiments. Full IR filters give different effects.

Focus:
With wide angle lenses, shooting distant subjects with a small aperture, (such as landscape) focus will not be difficult.

With telephoto lenses, with closer subjects and a wider aperture (such as portraits) focus may need adjustment.

This lens has a white 'dot' next to the number '11' on the left of the barrel:


On this lens 'Normal' focus is 2.5m - but if you're shooting in IR you need to manually over-ride the focus to place 2.5m above the little white dot. Simple.

Older cameras are often better for these unusual processes - they don't have electronic film counters that can fog IR film, and have useful 'extras' like 'IR focus dots' - that disappeared in the 1990s when manufacturers began to cut costs on amateur cameras.