B&W Film H&D Characteristic Curve, True EI Speed & Zone-System Development Calibrator

Deterministic Logarithmic transmittance-to-density D = -log10(I/I0) spline fit + ISO 6 speed point (0.10 above B+F) + Kodak Contrast Index arc slope engine (.dng, .tiff, .arw, .nef) built for Ilford Photo, Kodak Tri-X, Adox / Rodinal, Jobo — zero-upload ephemeral Wasm RAM execution.

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Double-click 2.4× zoom · Drag to pan / 3D orbit

Free Deterministic X-Ray Preview

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