From 15c94b9f0845311e6328eda25ee76c3db7227387 Mon Sep 17 00:00:00 2001 From: Claude Date: Sat, 17 Oct 2026 18:12:01 +0000 Subject: [PATCH 1/3] sigmoid: allow target white above 1600% for HDR output With PQ output 100% is the 203 nit reference white, so the 1600% hard limit capped a sigmoid edit at about 3250 nits while PQ reaches 10000. Raise the hard maximum to 5000%, about 10150 nits and so the top of the PQ range, and keep the 50-100% soft range so the slider is unchanged for SDR work. The tooltip now explains how to use the value for HDR output. Fixes #22665 Co-Authored-By: Claude Opus 5.5 (1M context) Claude-Session: https://claude.ai/code/session_01HsykTqvsWoMew3BXJWE2KA --- src/iop/sigmoid.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/src/iop/sigmoid.c b/src/iop/sigmoid.c index bfdba9731e3..dd96094495c 100644 --- a/src/iop/sigmoid.c +++ b/src/iop/sigmoid.c @@ -58,7 +58,7 @@ typedef struct dt_iop_sigmoid_params_t { float middle_grey_contrast; // $MIN: 0.1 $MAX: 10.0 $DEFAULT: 1.5 $DESCRIPTION: "contrast" float contrast_skewness; // $MIN: -1.0 $MAX: 1.0 $DEFAULT: 0.0 $DESCRIPTION: "skew" - float display_white_target; // $MIN: 20.0 $MAX: 1600.0 $DEFAULT: 100.0 $DESCRIPTION: "target white" + float display_white_target; // $MIN: 20.0 $MAX: 5000.0 $DEFAULT: 100.0 $DESCRIPTION: "target white" float display_black_target; // $MIN: 0.0 $MAX: 15.0 $DEFAULT: 0.0152 $DESCRIPTION: "target black" dt_iop_sigmoid_methods_type_t color_processing; // $DEFAULT: DT_SIGMOID_METHOD_PER_CHANNEL $DESCRIPTION: "color processing" float hue_preservation; // $MIN: 0.0 $MAX: 100.0 $DEFAULT: 100.0 $DESCRIPTION: "preserve hue" @@ -969,7 +969,11 @@ void gui_init(dt_iop_module_t *self) dt_bauhaus_slider_set_soft_range(slider, 50.0f, 100.0f); dt_bauhaus_slider_set_format(slider, "%"); gtk_widget_set_tooltip_text(slider, _("the white luminance of the target display or print.\n" - "can be used creatively for a faded look or blowing out whites earlier.")); + "can be used creatively for a faded look or blowing out whites earlier.\n" + "for HDR (PQ or HLG) output, raise it above " + "100 percent to give highlights headroom;\n" + "100 percent is the 203 nit reference white, " + "so 1000 nits is about 493 percent")); self->widget = main_box; } From 6b74428dbf22a739f70de82c960dd29f37a262e1 Mon Sep 17 00:00:00 2001 From: Claude Date: Sat, 17 Oct 2026 18:12:01 +0000 Subject: [PATCH 2/3] RELEASE_NOTES.md: sigmoid target white up to 5000% for HDR Co-Authored-By: Claude Opus 5.5 (1M context) Claude-Session: https://claude.ai/code/session_01HsykTqvsWoMew3BXJWE2KA --- RELEASE_NOTES.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md index 27a9b4ee27f..680186c6381 100644 --- a/RELEASE_NOTES.md +++ b/RELEASE_NOTES.md @@ -244,6 +244,11 @@ changes (where available). light level metadata (MaxCLL and MaxFALL) when built with libavif 1.0.0 or newer. +- Sigmoid's target white can now be set up to 5000%, instead of 1600%, + to leave more headroom for PQ and HLG exports. 100% is the 203 nit HDR + reference white, so the new limit reaches about 10000 nits, the top of + the PQ range. The slider's default range is unchanged. + - The external raster masks module imports its mask into the image's `.dtdata` sidecar instead of referencing a file in a root folder. Each instance holds one imported mask. Existing edits that point at From 050bebd82ad124b0c37d323b8e05f33c7f6ccdb4 Mon Sep 17 00:00:00 2001 From: Nicholas Nezis Date: Sun, 18 Oct 2026 06:06:52 -0400 Subject: [PATCH 3/3] Replace "percent" with % --- src/iop/sigmoid.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/iop/sigmoid.c b/src/iop/sigmoid.c index dd96094495c..c3f50accb81 100644 --- a/src/iop/sigmoid.c +++ b/src/iop/sigmoid.c @@ -971,7 +971,7 @@ void gui_init(dt_iop_module_t *self) gtk_widget_set_tooltip_text(slider, _("the white luminance of the target display or print.\n" "can be used creatively for a faded look or blowing out whites earlier.\n" "for HDR (PQ or HLG) output, raise it above " - "100 percent to give highlights headroom;\n" + "100 % to give highlights headroom;\n" "100 percent is the 203 nit reference white, " "so 1000 nits is about 493 percent"));