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* Camera Raw: Whites, Blacks, Shadows and Highlights closer to Photoshop's Measured as a black box on Photoshop 25.4's Camera Raw Filter. Whites and Blacks are global curves of the grey level: the measured rows per slider value, Whites first, after Shadows and Highlights. The clipping directions adapt to the image's black and white points (Whites up to 2.7 times stronger on a dark image, Blacks at least 1.2). On ten public-domain photos the mean error against Photoshop drops from 4.2-36.8 to 0.9-8.9 levels of 255. Shadows and Highlights are a local Laplacian filter (Paris et al. 2011, fast form of Aubry et al. 2014) on the log luminance, the method Adobe credits for process version 2012. Shadows raises pixels darker than their surroundings by an amount set by their own and their surroundings' tone, so big edges keep no halo, and keeps the 99th percentile; Highlights pulls pixels brighter than their surroundings toward them and keeps the 1st. The strengths are fitted to the photos (mean error 2.8-9.4 levels, was 3.7-14.3); Photoshop's exact operator was not recovered. The tone stages decode light with the document's curve: filter.cameraRaw stores encodingGamma (1.8 for ProPhoto, where raws open). Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]> * Camera Raw Shadows/Highlights: no contour lines on smooth gradients Twelve reference values over a raw's whole range left more than a stop between them, and the remapping changes within half a stop: coefficients interpolated across that gap drew contour lines in out-of-focus areas (Shadows +100 on a Nikon D4 raw). References are now an eighth of a stop apart over the image's tones (the deepest 0.1 % share the lowest), on a copy at most 1600 px across whose change comes back to full size by a guided upsampling, so a 16-megapixel image takes about 2 s per slider and the preview matches the result. Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]> * Camera Raw on raw opens: Shadows/Highlights in linear light, D4 look and black point as Photoshop Measured black-box on 29 Nikon D4 NEFs opened through Camera Raw in Photoshop 25.4 (sliders at +-100 and +50, exposure +-1) against our own linear development of the same files. - Shadows and Highlights of the open-time dialog now act while developing, in linear light before the tone curve, as Camera Raw does for raw files (exposure -1 gives the same gains). The log2 gain is slider/100 * C(B - anchor): B is a guided-filter base of the log2 luminance on a copy 1232 px on its long side, the anchor is image-adaptive (Shadows: log2 power mean p=1.5 of the linear luminance; Highlights: mean log2 luminance). New module photocraft_raw::tone; the preview undoes the camera curve to show the same (photocraft_raw::retone). - The D4 profile copies Camera Raw's default rendering: look matrix folded into the ForwardMatrix, per-channel curve, and an adaptive black point (0.33 x the 0.1th percentile of the luminance, Sensor::black_point). Against Photoshop on the 29 frames (1/4 size, log2 Y): default rendering median difference 0.29 -> 0.04 stop; correlation of the slider's effect Shadows +100 0.96, -100 0.91, Highlights -100 0.87, +100 0.85 (the previous filter model: 0.68 and 0.55 on DSG_3464). Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]> * docs: the open-time Camera Raw re-develop covers Shadows and Highlights Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]> * Camera Raw raw-stage Shadows: keep shadow contrast as Photoshop does The user saw Photoshop's shadows sink deeper with more contrast. Measured on the 29 D4 NEFs: with Shadows +100 our shadow detail had 0.79 of Photoshop's local contrast and shadows sat 0.38 stop lighter. Two causes: - The black point now comes before the Shadows / Highlights gain, as in Camera Raw (lifting first let the lift wash out the black point's deep-shadow contrast). - The guided upsampling's epsilon goes from 0.01 to 1 stop^2: the change follows strong edges but stays smooth inside texture (with 0.01 it followed every detail and flattened it). Near strong edges the effect still matches Photoshop as well as elsewhere. Shadows +100: shadow detail 0.79 -> 0.91, shadow bias +0.38 -> +0.16 stop; effect correlation Shadows -100 0.906 -> 0.946, Highlights -100 0.870 -> 0.886, others unchanged. Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]> * Camera Raw on raw opens: Clarity, Texture and Dehaze in linear light, as Photoshop Measured black-box from Photoshop 25.4 opening 29 Nikon D4 NEFs through Camera Raw (descriptor keys Cl12, CrTx, Dhze; each at ±100 and +50, and +100 at exposure −1, 348 opens). All three act before the tone curve: the change at exposure −1 equals the one at 0 (correlation 0.98–0.99). - Clarity: log2 luminance split into bands between guided-filter bases (radii 2, 8, 32, 128 on the 1232 px work copy), each band scaled by a measured gain that follows its base's tone, plus a tone term; carried to full size with the Shadows / Highlights change. - Texture: Gaussian bands σ 0.5…16 on a half-size copy, each through its measured response (small detail raised more than strong edges, flat areas unchanged), guided-upsampled. - Dehaze: He, Sun and Tang's dark channel prior on linear ProPhoto (dark channel in Display P3, airlight from the brightest 0.1 % of it, guided-smoothed transmission), w 0.8 at +100; −100 a uniform veil. The black point stays the default rendering's. Against Photoshop, PhotoCraft's develop vs Photoshop's open on all 29 frames (median effect correlation, log2 luminance at 1/4 size, Texture at 1/2): Clarity +100 0.81, −100 0.85; Texture +100 0.85, −100 0.88; Dehaze +100 0.61 (0.78 in gamma 2.2: the crushed shadows differ), −100 0.96. Shadows / Highlights unchanged (0.964 / 0.886). The open-time Camera Raw dialog re-develops for them and its preview shows them (retone). Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]> --------- Co-authored-by: Claude Opus 5.5 (1M context) <[email protected]> Co-authored-by: Brandon Thomas <[email protected]>