· 3 min read
Selenium, CdS, and Silicon Meter Cells Compared
How selenium, cadmium-sulfide, and silicon photodiode meter cells differ in spectral response, memory effect, and low-light accuracy.
For people obsessed with film — and the grain it leaves behind. grainmag is a publication about black-and-white photography the slow way: metering by hand, reading the light in zones, and earning the negative in the darkroom. No filters, no gear-of-the-week hype — just the craft and patience analog demands.
Featured reading
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· 3 min read
Dry-down: why fibre prints darken on drying, and how to compensate
Fibre prints darken and flatten as they dry. How to measure the dry-down percentage and adjust exposure and contrast so the dry print matches the wet judgement.
· 4 min read
Panchromatic vs Orthochromatic Film: Spectral Response and Tonal Rendering
How orthochromatic film's blindness to red darkens skin and reds while panchromatic emulsions record the full spectrum, and what each does to tone.
· 4 min read
Pre-Exposure: Flashing Film to Register Deep Shadow Detail
How a uniform sub-threshold exposure before the main exposure lifts deep shadows past the film's threshold while leaving highlights almost untouched.
· 3 min read
Spot Metering the Shadow and Placing It on Zone III
How a spot meter reading of the darkest important shadow, placed two stops down on Zone III, secures shadow detail in a negative.
The grainmag companion app
An offline exposure & Zone System companion
Meter and place your tones without a signal. No account, no internet required — just you, the light, and the grain.