Color negative films developed with the standard C-41 process feature an integral chemical orange polymer base (azo dye mask) formulated to compensate for secondary absorption characteristics of cyan and magenta dyes. Inverting a camera scan with generic image inversion software yields an unusable blue-cyan color cast.

This utility removes the orange mask base and balances tonal curves directly inside your browser. It offers calibrated stock presets for popular films (Kodak Portra 400, Kodak Gold 200, Fuji Superia 400, and Black & White), individual red, green, and blue mask density controls, non-linear gamma curve adjustments, and color temperature/tint fine-tuning.

For example, loading a camera scan of a 35mm Kodak Portra negative and applying the Portra preset subtracts the amber mask (R: 218, G: 132, B: 62) and applies a 1.25 gamma curve, revealing natural skin tones and neutral highlights. The interactive split-slider allows you to swipe between the raw orange negative and the developed positive photograph.

All pixel operations execute locally on an HTML5 canvas in your web browser. Scanned film photographs are never uploaded or saved to remote servers.