diff --git a/ui/dr-ui/src/library_ui/ratings_keywords.rs b/ui/dr-ui/src/library_ui/ratings_keywords.rs
index d3571ec..20074c2 100644
--- a/ui/dr-ui/src/library_ui/ratings_keywords.rs
+++ b/ui/dr-ui/src/library_ui/ratings_keywords.rs
@@ -454,6 +454,20 @@ fn apply_judgement(
     start_xmp_writes(window, ctl, images);
 }
 
+/// TRACES: FR-UI-5 | FR-CULL-4
+/// The photograph at one row of the loaded window, for the gestures that
+/// name a single photograph: a star clicked on a cell, and develop's keys
+/// and top bar, which name the open one by its roll row.
+///
+/// `None` for a negative row as well as one past the end. Develop passes
+/// `-1` when the open photograph is not in the window, and the answer then
+/// is to judge nothing — never to fall back on the grid's selection, which
+/// is not what is on screen.
+fn image_at_row(ids: &[i64], row: i32) -> Option<dr_types::ImageId> {
+    let row = usize::try_from(row).ok()?;
+    ids.get(row).map(|id| dr_types::ImageId(*id as u64))
+}
+
 /// What the status line says about a judgement that just landed.
 fn judgement_summary(n: usize, rating: Option<u8>, flag: Option<dr_types::FlagState>) -> String {
     let what = match (rating, flag) {
@@ -975,12 +989,9 @@ pub(super) fn wire_ratings_and_flags(
             .global::<Library>()
             .on_library_cell_rated(move |row, stars| {
                 let Some(w) = weak.upgrade() else { return };
-                let id = ctl
-                    .image_ids
-                    .borrow()
-                    .get(row as usize)
-                    .map(|id| dr_types::ImageId(*id as u64));
-                let Some(id) = id else { return };
+                let Some(id) = image_at_row(&ctl.image_ids.borrow(), row) else {
+                    return;
+                };
 
                 apply_judgement(&w, &ctl, &[id], Some(stars.clamp(0, 5) as u8), None);
             });
@@ -998,12 +1009,9 @@ pub(super) fn wire_ratings_and_flags(
             .global::<Library>()
             .on_library_cell_flagged(move |row, flag| {
                 let Some(w) = weak.upgrade() else { return };
-                let id = ctl
-                    .image_ids
-                    .borrow()
-                    .get(row as usize)
-                    .map(|id| dr_types::ImageId(*id as u64));
-                let Some(id) = id else { return };
+                let Some(id) = image_at_row(&ctl.image_ids.borrow(), row) else {
+                    return;
+                };
 
                 apply_judgement(&w, &ctl, &[id], None, Some(flag_from_code(flag)));
             });
@@ -1158,12 +1166,9 @@ pub(super) fn wire_ratings_and_flags(
                 let Some(gesture) = LabelGesture::from_code(code, toggle) else {
                     return;
                 };
-                let id = ctl
-                    .image_ids
-                    .borrow()
-                    .get(row as usize)
-                    .map(|id| dr_types::ImageId(*id as u64));
-                let Some(id) = id else { return };
+                let Some(id) = image_at_row(&ctl.image_ids.borrow(), row) else {
+                    return;
+                };
                 apply_label(&w, &ctl, &[id], gesture);
             });
     }
@@ -1237,6 +1242,62 @@ pub(super) fn wire_keywords(
 mod tests {
     use super::*;
 
+    // --- judging the photograph open in develop (FR-UI-5) -----------------
+
+    /// TRACES: FR-UI-5
+    #[test]
+    fn a_row_names_one_photograph_and_no_row_names_none() {
+        let ids = [11, 22, 33];
+        assert_eq!(image_at_row(&ids, 1), Some(dr_types::ImageId(22)));
+        assert_eq!(image_at_row(&ids, 3), None);
+        // The open photograph outside the loaded window: nothing is judged,
+        // rather than whatever the grid last had selected.
+        assert_eq!(image_at_row(&ids, -1), None);
+        assert_eq!(image_at_row(&[], 0), None);
+    }
+
+    /// The `if (Keys.chord(event) == "<key>") { … }` line of develop's
+    /// key handler that binds `key`.
+    fn develop_binding(key: &str) -> &'static str {
+        let app = include_str!("../../ui/app.slint");
+        let scope = &app[app
+            .find("// KEYMAP: Develop\n                        key-pressed(event)")
+            .expect("app.slint no longer has develop's key-pressed handler")..];
+        let needle = format!("if (Keys.chord(event) == \"{key}\") {{");
+        let at = scope
+            .find(&needle)
+            .unwrap_or_else(|| panic!("develop does not bind `{key}`"));
+        scope[at..].lines().next().unwrap_or("")
+    }
+
+    /// TRACES: FR-UI-5 | FR-CULL-4
+    /// 0–5, P, X and U in develop judge the open photograph — its roll row —
+    /// and do nothing else: no step to the next frame, which belongs to
+    /// culling's auto-advance and not to the view where one frame is worked on.
+    #[test]
+    fn develop_judges_the_open_photograph_and_stays_on_it() {
+        for (key, call) in [
+            ("0", "library-cell-rated(Library.library-roll-current, 0)"),
+            ("1", "library-cell-rated(Library.library-roll-current, 1)"),
+            ("2", "library-cell-rated(Library.library-roll-current, 2)"),
+            ("3", "library-cell-rated(Library.library-roll-current, 3)"),
+            ("4", "library-cell-rated(Library.library-roll-current, 4)"),
+            ("5", "library-cell-rated(Library.library-roll-current, 5)"),
+            ("P", "library-cell-flagged(Library.library-roll-current, 1)"),
+            ("X", "library-cell-flagged(Library.library-roll-current, 2)"),
+            ("U", "library-cell-flagged(Library.library-roll-current, 0)"),
+        ] {
+            let line = develop_binding(key);
+            assert!(line.contains(call), "`{key}` in develop: {line}");
+            for step in ["step-photo", "roll-pick", "move-cursor"] {
+                assert!(
+                    !line.contains(step),
+                    "`{key}` in develop also steps: {line}"
+                );
+            }
+        }
+    }
+
     // --- what a judgement key reaches (FR-UI-5) ----------------------------
 
     #[test]