Design your
own stocks.
Be the chemist.

We reverse-engineer your digital RGB into a 43-band spectrum using the dye-sensitivity controls. That estimates where silver halide is likely to become metallic silver, and which emulsion dyes form where — giving physically plausible light distributions to work from.

Once we map where silver activates, we shape the density response with the HD curves — taking a linear scene exposure and letting shadows hang on longer while highlights roll off gracefully. Grain appears where silver that should have activated doesn't, leaving a slightly different density than its neighbours. Halation models light that scattered back through the stock, leaving that signature reddish halo bleeding around highlights.

The three dyes are simulated as asymmetric Gaussian absorption curves, matchable to real film chemistry — and the latest update resolves those absorption curves across the same 43-band spectrum as the sensitivities, for true spectral accuracy. Density is which wavelengths a dye absorbs; transmission is what it lets pass. What you see at the end is the transmission — the light that remains.

Controls here develop the latent image. Push / Pull is the headline move — it's how long the stock sits in the developer, letting more or less dye form where metallic silver is present. Tweak it to lift or crush the whole response.

Bleach Bypass controls how much metallic silver is washed away or retained during development. Beyond it sit the finer moves — Midtone Expansion, Developer Competition, Chroma Expansion, Dye Inhibition and Spectral Separation — each accounting for a real aspect of stock design to pull out the richest tones and colors. Bias controls apply all of this per layer.

Now your negative is developed, Stage 08 is the printer lights. We model transmission through the negative with the Beer–Lambert law and let you design the color and power of the light used to expose the next stock. This is the hand-off from negative to print.

Here's the part that makes it a true photochemical chain: stages 09 through 17 repeat the whole 1–8 process, now geared toward creating a print film from the printer light leaving the negative. That print stock is then sampled through a projector simulation — so what lands on screen isn't your input colors or even the dye colors, but the light that survives the composite dyes of negative and print.