5 Commits

Include renames

Author	SHA1	Message	Date
dtourolleandClaude Opus 5	ff1a3e0e80	Print the black-and-white negatives instead of showing the scan ... Choosing Ilford HP5 Plus showed an inverted grey frame. So did Double-X. They are negatives, and upstream leaves `target_print` null on every monochrome stock, so nothing was ever printed and the scan was all there was. A colour negative at least announces itself -- the orange mask says plainly that you are looking at a negative. A monochrome one just looks broken. They print on Kodak 2302 now, which is a monochrome print film and is what such a negative is actually printed onto; Double-X onto 2302 is the standard cine chain. For the Ilford stocks it stands in for an Ilford paper, which nobody has measured, and is at least the right kind of material. The scan is still reachable through the Scanned/Printed toggle. It is a thing to choose now rather than the only thing on offer. `every_shipped_stock_bakes` did not catch this, and could not: it derives "should this be inverted?" from the stock's kind *and whether it names a paper*, so it looked at an inverted HP5, concluded that was right for an unprinted negative, and passed. The assertion was self-consistent and the situation was still wrong. The new test asserts the thing that actually matters -- a camera negative must name a paper, that paper must be a printing stock, and it must be the same kind of material, so a monochrome negative cannot end up on colour paper. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>	2026-08-26 17:35:25 +02:00
dtourolleandClaude Opus 5	ce6458547a	Develop longer, from the measurements rather than from a contrast slider ... Pushing was not a thing to simulate. It was measured data being thrown away: Double-X and 2302 each ship five characteristic curves, one per development time, and this shipped the 6.5-minute column and discarded four. All five now ship and interpolate. The axis is real. Double-X runs 4 to 12 minutes, and across it the average gradient goes 0.472 to 1.034 while Dmax goes 1.19 to 2.56. The control is in stops, because that is what a photographer means, and one stop is a factor of about 1.41 in time. That mapping is checked rather than assumed: against Double-X's own axis it lands within 2% of the 9-minute column for +1, and near 12 minutes for +2, which are the times the datasheet gives for exactly that. There is a test. **Pushing must not recover shadow detail, and this does not.** Across the whole measured range the speed point moves about a third of a stop while the gradient doubles; three stops under mid-grey, density goes from 0.008 to 0.035, which is still nothing. Developing longer multiplies what was already recorded and cannot record what never hit the film. A push built as added exposure or global contrast brightens those shadows instead and looks convincing until someone who shoots film sees it, so that property has a test of its own. Interpolated in *log* time, because development is multiplicative: 4 to 5 minutes is the same amount of push as 9 to 12, and interpolating linearly would bunch the control at one end. Clamped at both ends, because past the published range there is no data and extrapolating a contrast curve invents an emulsion nobody tested. A stock measured at one process ignores the control entirely rather than inventing a curve for it -- Portra 800's pushes are separate *measured* profiles, which is the honest way to offer those. Costs nothing per pixel and changes no shader. The curves are a per-stock table, so the interpolation happens on the CPU at bake time, where choosing a stock and moving its sliders already rebakes. The Vulkan shader is untouched. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>	2026-08-26 17:35:25 +02:00
dtourolleandClaude Opus 5	e9b3598841	Add five Ilford stocks, and say plainly that they are constructed ... They were asked for and they are here, but not on the same footing as the Kodak profiles, and the files say so in their first line. What I had claimed, and had to withdraw: that Delta 100 is "quoted around 9" and HP5 "around 12". Ilford publish no such figures. The word granularity does not occur anywhere in their technical information -- grain is described as "fine" and "finest" and nothing more. That claim was in this crate's documentation as though it came from a datasheet; it is corrected there too. Two further traps found while looking: - Kodak colour negatives publish Print Grain Index, not RMS granularity. PGI is a perceptual scale from viewer surveys -- 25 is roughly the threshold of visibility, four units a just-noticeable difference -- and Kodak state it cannot be compared to RMS. So a Portra number cannot be dropped into the granularity field, and none has been. - RMS proper is published mostly for black-and-white, reversal and motion picture stocks. Every shipped stock therefore still carries the same default, which means grain does not yet tell one film from another. That is per-stock data, not code, and is now written down where somebody will find it. So the Ilford profiles are built rather than extracted, and each part rests on something different: speed published and exact -- ISO 400/27 for HP5 is a fact contrast ISO 6:1993's normal development, average gradient 0.62 spectral borrowed from Kodak Double-X, a *measured* panchromatic negative, shifted by the speed difference. Conventional panchromatic sensitisation is much alike across black-and-white films, and this is far better founded than reading pixels off a printed curve silver neutral, which is not an approximation: developed silver absorbs flat, and Double-X's measurement is flat granularity estimated, ordered by each film's known relative grain They render as a film of that speed and contrast. They are not a measurement of that emulsion, and the two stocks that share a speed differ only in the estimated part. `every_shipped_stock_bakes` is tightened to match, because a constructed profile fails in a way a measured one does not: the curve parses, bakes, and sits entirely off one end of its own exposure range, rendering every frame black or blown while passing a finiteness check. It now asserts mid-grey lands somewhere photographic and that the tone response runs the way the stock's kind says it should. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>	2026-08-26 10:08:51 +02:00
dtourolleandClaude Opus 5	6d18517d28	Ship every stock that exists, black and white included ... Three profiles was what the first cut needed to prove the model. This is the rest of the open data: 23 camera stocks and 9 papers, which is all of spektrafilm. Black and white was the gap, and it turned out not to be a gap in the data -- it was a gap in where I looked. Upstream's `main` has 28 colour profiles and nothing monochrome; `dev` has three more, and they are Tri-X, Double-X and the 2302 print film they go onto. So the answer to "do we have B&W" was yes all along, and it needed the dev branch rather than a fortnight digitising Ilford's datasheet graphs by eye. Those three are pinned to `dev` per stock; the colour stocks stay on the released branch. A monochrome profile is single-channel -- one emulsion, not three -- and spreading that one layer across all three is exact rather than an approximation: three layers with identical sensitivity and identical curves respond identically, which is what one layer does. The dye is the trap. The renderer *sums* the three layers' contributions, so replicating it unchanged renders every frame three times too dense -- neutrally, and therefore plausibly. A third each reconstructs the single emulsion, and two tests hold both halves: that the densities stay equal, and that they sum to one emulsion and not three. Double-X and 2302 ship five curves apiece, measured at five development times -- 4 to 12 minutes for Double-X. That is push and pull processing as measured data. The standard 6.5 minutes is what ships; the rest is in the upstream file waiting for a control to ask for it. Two stocks are `support: film` and are nevertheless what a negative is printed *onto*: the cine projection films 2383 and 2393, which the Vision3 stocks print to. Filtering the picker on support alone offered a projection stock as something to load in a camera, so it filters on stage, with a test saying so. The picker had to change shape twice over. Chips were right for three stocks and off the edge of a 280px column at twenty-four, and the column that replaced them was a thousand pixels standing between the photographer and every slider below. It is a disclosure now: one row carrying the answer, opened to change it, closed again on choosing. That is the opposite of the argument this panel used to take the lids off its sliders, and deliberately so -- an instrument you compare wants to be visible, and a list you consult once wants to be out of the way. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>	2026-08-25 20:30:11 +02:00
dtourolleandClaude Opus 5	b6a95e1965	Simulate a film stock from its measurements, not from someone's grade ... FR-DEV-3f asks for look emulation and proposes HaldCLUT import to inherit the free film-simulation ecosystem. This takes the other road for the stocks where the measurements exist: run the physics. A stock here is its manufacturer's own datasheet -- spectral sensitivity, characteristic curves, dye densities. Light exposes three emulsion layers, the layers develop to densities, the densities are dyes that absorb, and what is left is what reaches the eye. A colour negative comes out orange and upside down because that is what a colour negative is; it becomes a photograph when a paper profile prints it, with the enlarger's filtration solved rather than dialled. What that buys over a LUT is that the parameters stay physical. Opening up a stop moves the picture along the film's real characteristic curve, shoulder and all, instead of scaling a number baked at one exposure. The data cost runs the other way too: a stock is 17 kB of published measurements where one HaldCLUT is 800 kB of one person's grade. It looks like it needs a spectral integration per pixel. It does not, and that is the whole design: - Exposure is a 3x3 matrix. The reconstructed scene spectrum is linear in the sRGB triple, so the integral collapses into nine numbers, exactly -- no approximation. - The characteristic curve is three 1D functions, sampled exactly. - Everything after that -- dye absorption, the print through the negative, the paper, the viewing illuminant, the adaptation -- takes exactly three numbers in, so it bakes into one 32^3 lookup. Per pixel: a matrix multiply, three curve taps, one fetch. Splitting the curve out of the 3D lookup rather than baking one LUT over exposure is measured, not assumed: the curve carries the sharp shape and the dye mixing is smooth, so folding them together would need three times the resolution for the same error. At 32^3 the worst error is 0.003 in linear sRGB, under one 8-bit code value, and a test says so. No wgpu dependency, deliberately, and the same isolation argument dr-lens makes: the model is plain f32 with a documented layout, so every property worth asserting is asserted on the CPU. Binding it to a texture is dr-gpu's job and is not done here yet. The expected values in tests/ came from a Python prototype running against a different colour-science stack. Agreement to three decimals is evidence about the model rather than about one implementation of it -- a transposed matrix or a mispasted observer row would pass every unit test and fail that one. Profiles are converted from spektrafilm by Andrea Volpato, CC BY-SA 4.0. The converter is in the tree and runnable, so what was changed from upstream is auditable rather than taken on trust; profiles/CHANGELOG.txt records it, including the one deliberate deviation -- Mallett & Yuksel's 1 kB basis instead of Hanatos's 4 MB table, which costs accuracy at the gamut edge and saves four megabytes. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>	2026-08-25 14:44:54 +02:00