diff --git a/crates/ui-egui/src/preset_panels.rs b/crates/ui-egui/src/preset_panels.rs
index 94ee84b4..15ac94f4 100644
--- a/crates/ui-egui/src/preset_panels.rs
+++ b/crates/ui-egui/src/preset_panels.rs
@@ -1128,4 +1128,19 @@ mod tests {
         app.session.presets.clone.active_mut().anchor = Some([20.0, 20.0]);
         assert_eq!(clone_sample_point(&app, Some([30.0, 30.0])), Some([20.0, 20.0]));
     }
+
+    #[test]
+    fn clone_marker_shows_only_while_painting() {
+        // #668: ⌥-click used to leave a "+" on the canvas until the next stroke.
+        let (mut app, _) = app();
+        app.ui.tool = Tool::CloneStamp;
+        crate::retouch_ui::set_source(&mut app, 10.0, 10.0);
+        app.hover_doc = Some([40.0, 40.0]);
+        assert_eq!(crate::retouch_ui::source_marker_point(&app), None, "hovering after ⌥-click shows nothing");
+        app.drag = Some(crate::canvas::Drag::new(Tool::CloneStamp, [40.0, 40.0], vec![[40.0, 40.0, 1.0]], egui::Modifiers::NONE, false));
+        assert!(crate::retouch_ui::source_marker_point(&app).is_some(), "painting shows where it samples");
+        app.drag = None;
+        app.ui.tool = Tool::Brush;
+        assert_eq!(crate::retouch_ui::source_marker_point(&app), None);
+    }
 }
diff --git a/crates/ui-egui/src/retouch_ui.rs b/crates/ui-egui/src/retouch_ui.rs
index bd388192..4f22a09b 100644
--- a/crates/ui-egui/src/retouch_ui.rs
+++ b/crates/ui-egui/src/retouch_ui.rs
@@ -169,20 +169,23 @@ pub fn set_source(app: &mut PhotocraftApp, x: f64, y: f64) {
     app.ui.status_error = false;
 }
 
-/// Crosshair where the clone source is sampled from for the current pointer position.
-pub fn draw_source_marker(app: &PhotocraftApp, painter: &egui::Painter, xf: &ViewXform) {
+/// Where the clone source is sampled from, shown only while a Clone Stamp or Healing Brush stroke
+/// is painted, as in Photoshop: setting the source (⌥-click) leaves nothing on the canvas (#668).
+pub fn source_marker_point(app: &PhotocraftApp) -> Option<[f64; 2]> {
     if !matches!(app.ui.tool, Tool::CloneStamp | Tool::Healing) {
-        return;
+        return None;
     }
-    let at =
-        app.drag.as_ref().filter(|d| matches!(d.tool, Tool::CloneStamp | Tool::Healing)).and_then(|d| d.points.last().map(|p| [p[0], p[1]])).or(app.hover_doc);
-    let src = match (crate::preset_panels::clone_sample_point(app, at), app.ui.clone_offset, at, app.ui.clone_source) {
+    let at = app.drag.as_ref().filter(|d| matches!(d.tool, Tool::CloneStamp | Tool::Healing)).and_then(|d| d.points.last().map(|p| [p[0], p[1]]))?;
+    match (crate::preset_panels::clone_sample_point(app, Some(at)), app.ui.clone_offset, app.ui.clone_source) {
         (Some(p), ..) => Some(p),
-        (None, Some(off), Some(h), _) => Some([h[0] + off[0], h[1] + off[1]]),
-        (None, None, _, Some(s)) => Some(s),
-        _ => None,
-    };
-    let Some(s) = src else { return };
+        (None, Some(off), _) => Some([at[0] + off[0], at[1] + off[1]]),
+        (None, None, s) => s,
+    }
+}
+
+/// Crosshair at [`source_marker_point`].
+pub fn draw_source_marker(app: &PhotocraftApp, painter: &egui::Painter, xf: &ViewXform) {
+    let Some(s) = source_marker_point(app) else { return };
     let c = xf.to_screen(s[0] as f32, s[1] as f32);
     for (w, col) in [(3.0, Color32::from_black_alpha(160)), (1.0, Color32::WHITE)] {
         painter.line_segment([c - vec2(7.0, 0.0), c + vec2(7.0, 0.0)], Stroke::new(w, col));