diff --git a/crates/engine/src/lens_cmds.rs b/crates/engine/src/lens_cmds.rs
index 379ca2402a..9a566fb925 100644
--- a/crates/engine/src/lens_cmds.rs
+++ b/crates/engine/src/lens_cmds.rs
@@ -147,6 +147,9 @@ pub fn raw_params(cmd: &str, p: &Value) -> Result<CameraRaw> {
     cr.noise_luminance_detail = cr.noise_luminance_detail.clamp(0.0, 100.0);
     cr.noise_color = cr.noise_color.clamp(0.0, 100.0);
     cr.noise_color_detail = cr.noise_color_detail.clamp(0.0, 100.0);
+    // `exposure` becomes `2^exposure`, which overflows f32 to infinity from 128 up (and then
+    // writes inf/NaN into 32-bit layers). Clamp to the documented -5..5.
+    cr.exposure = cr.exposure.clamp(-5.0, 5.0);
     Ok(cr)
 }
 
diff --git a/crates/engine/tests/camera_raw_exposure_clamp.rs b/crates/engine/tests/camera_raw_exposure_clamp.rs
new file mode 100644
index 0000000000..ee624f7e28
--- /dev/null
+++ b/crates/engine/tests/camera_raw_exposure_clamp.rs
@@ -0,0 +1,40 @@
+//! `filter.cameraRaw` must clamp `exposure` to its documented -5..5 range. Before the fix,
+//! `raw_params` passed it through, so an exposure of 128 or more overflowed `2^exposure` to
+//! infinity and a 32-bit layer was left with non-finite samples.
+
+use photocraft_engine::Session;
+use serde_json::json;
+
+#[test]
+fn camera_raw_clamps_exposure() {
+    let hi = photocraft_engine::lens_cmds::raw_params("filter.cameraRaw", &json!({"exposure": 255.0})).expect("params parse");
+    assert_eq!(hi.exposure, 5.0, "exposure 255 must clamp to 5");
+    let lo = photocraft_engine::lens_cmds::raw_params("filter.cameraRaw", &json!({"exposure": -255.0})).expect("params parse");
+    assert_eq!(lo.exposure, -5.0, "exposure -255 must clamp to -5");
+    let mid = photocraft_engine::lens_cmds::raw_params("filter.cameraRaw", &json!({"exposure": 1.5})).expect("params parse");
+    assert_eq!(mid.exposure, 1.5, "in-range exposure stays untouched");
+}
+
+#[test]
+fn camera_raw_out_of_range_exposure_keeps_32_bit_layer_finite() {
+    for exposure in [255.0, -255.0] {
+        let mut s = Session::new();
+        s.execute("file.new", json!({"width": 8, "height": 8, "depth": 32})).unwrap();
+        s.execute("layer.new.layer", json!({})).unwrap();
+        s.execute("edit.fill", json!({"contents": "color", "color": "#ff0000"})).unwrap();
+        s.execute("filter.cameraRaw", json!({"exposure": exposure})).unwrap();
+        let st = s.active().unwrap();
+        let layer = st.active_layer.and_then(|id| st.doc.layer(id)).unwrap();
+        let surf = layer.surface().unwrap();
+        let mut bad = Vec::new();
+        for y in 0..8 {
+            for x in 0..8 {
+                let px = surf.rgba(x, y);
+                if px.iter().any(|v| !v.is_finite()) {
+                    bad.push(px);
+                }
+            }
+        }
+        assert!(bad.is_empty(), "exposure {exposure}: {} non-finite pixels, e.g. {:?}", bad.len(), bad.first());
+    }
+}