Merge branch lighting-prompt (the recorder asks for Daylight when sunlight comes in) into experimental

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

hands/rec/DESIGN.md

@@ -283,7 +283,7 @@ Before section 7: "Put on both controllers and tighten the straps". Before secti
 - **Hands seen:** from the hands file. A hand counts as seen if its flags match the side and the file is fresh (publish within 0.3 s). Prompts with `hands` set show the `hands` chips. If an asked-for hand is lost for more than 1.5 s, the note says "I can't see your left hand: bring it into view".
 - **Controller tracking:** in sections 8 and 9, `devices` is polled once a second. A result other than 200 for more than 1 s says "The left controller lost tracking: turn your palm slightly toward you". Each such stretch goes into `prompts.jsonl` as `feedback` with `"controller": {...}`.
 - **Lighting, measured:** the checklist page measures the light when it opens, starting ft-camd (`frametop-handrec-camd.service`) if nothing runs it; the window stops it again on quit if it started it. The mean of every mono camera's `mean` and `dark_mean` from the ring (`hands/tools/ring.py` layout; struct only, no numpy) is compared with the person's earlier sessions. If it matches an earlier round's within 15%, the window says so before starting.
-- **Lighting label:** "Measured by the cameras" is the default. `ambient_ir`, the mono cameras' mean `dark_mean` (the room's infrared), labels the round `daylight` from 6.0 and `indoor` below (`session.classify_lighting`). Lamps and LEDs give off hardly any infrared, so a dim room and a lit one read about the same (1.8 by one lamp, 2.2 in a lamp-lit room) and the cameras can't tell them apart; the person can pick dim, room or daylight instead (`source: "picked"`). The 6.0 threshold is a guess until a daylight round is measured.
+- **Lighting label:** "Measured by the cameras" is the default. `ambient_ir`, the mono cameras' mean `dark_mean` (the room's infrared), labels the round `daylight` from 6.0 and `indoor` below (`session.classify_lighting`). Lamps and LEDs give off hardly any infrared, so a dim room and a lit one read about the same (1.8 by one lamp, 2.2 in a lamp-lit room) and the cameras can't tell them apart; the person can pick dim, room or daylight instead (`source: "picked"`). The 6.0 threshold was a guess, and the first daylight round (dataset PR #5, 2026-10-05, a room with big sunlit windows) read 2.38 and was labelled `indoor`: the windows are a small part of each picture. So the checklist now asks people to pick Daylight when sunlight comes in, and the maintainer corrects the label in review (`hub_review.py lighting`) when hands stand out far less than in lamp light (PR #5: hands a median 1.15x as bright as their surroundings, against 1.5-1.7x).
 
 ### Camera check
 

hands/rec/main.qml

@@ -362,7 +362,8 @@ Kirigami.ApplicationWindow {
                     wrapMode: Text.Wrap
                     opacity: 0.7
                     text: "Each round in a different light helps the most: dim, a normal room, daylight. The cameras "
-                          + "tell daylight from indoor light themselves; to say dim or a normal room, pick it here."
+                          + "can't tell daylight on their own (a sunlit room has measured as indoor light), so if "
+                          + "sunlight comes into the room, pick Daylight here; dim or a normal room the same way."
                 }
                 Kirigami.InlineMessage {
                     Layout.maximumWidth: Kirigami.Units.gridUnit * 26

hands/rec/session.py

@@ -292,7 +292,7 @@ def similar_lighting(base_dir, lighting):
     return None
 
 
-DAYLIGHT_IR = 6.0   # ambient IR (the mono cameras' mean dark_mean) from which it's daylight
+DAYLIGHT_IR = 6.0   # ambient IR (the mono cameras' mean dark_mean) from which it's daylight; see classify_lighting
 
 
 def ambient_ir(ring):
@@ -306,7 +306,12 @@ def ambient_ir(ring):
 def classify_lighting(ring):
     """"daylight" or "indoor" from the room's infrared light, "" if it can't tell. Sunlight
     carries a lot of infrared; lamps and LEDs hardly any, so a dim room and a bright one read
-    about the same (2026-10: 1.8 by one lamp, 2.2 in a lamp-lit room) and aren't told apart."""
+    about the same (2026-10: 1.8 by one lamp, 2.2 in a lamp-lit room) and aren't told apart.
+    Nor does a sunlit room reliably: the first daylight round (dataset PR #5, big sunlit windows)
+    read 2.38, since the windows are a small part of each picture and the mean barely moves. So
+    "indoor" means "no strong daylight on the cameras", and the window asks people to pick
+    daylight themselves. What did show it there: hands only ~1.15x as bright as their surroundings
+    (1.5-1.7x in lamp-lit rooms), which needs hands in view, so it's measured on the dataset side."""
     ir = ambient_ir(ring)
     if ir is None:
         return ""