Update multiscale documentation to describe new level selection

docs/guides/rendering.md

@@ -273,6 +273,10 @@ As a part of these calculations, {attr}`Layer.corner_pixels<napari.layers.Layer.
 This means that whenever the canvas' camera is panned or zoomed, napari fetches all the data needed to draw the current field of view.
 While this can work well with local data, it will be slow with remote or other high latency data.
 
+This automatic level selection can be overridden by setting {attr}`locked_data_level<napari.layers.Image.locked_data_level>` on the layer.
+When set, the layer always renders at that specific level and `corner_pixels` spans the full extent of that level, bypassing the automatic computation described above.
+Setting it back to `None` restores automatic behavior.
+
 ### Loading non-image data
 
 Other layer types, like {class}`Points<napari.layers.Points>` and {class}`Shapes<napari.layers.Shapes>`, have layer specific data structures.

docs/howtos/layers/image.md

@@ -221,6 +221,30 @@ layer to specify if your data is a multiscale image or not. If you don't provide
 this value, then napari will try and guess whether your data is or needs to be a
 multiscale image.
 
+### Locking the multiscale level
+
+By default, napari automatically selects which resolution level to display based
+on the current zoom and viewport. In 2D this means zooming in loads
+higher-resolution data, while in 3D the coarsest level is used for performance.
+
+If you want to force a specific resolution level — for example, to keep a
+consistent view while panning or to inspect a particular level — you can set
+the `locked_data_level` property, or using the resolution dropdown in the layer controls:
+
+```python
+# Lock rendering to level 0 (highest resolution)
+layer.locked_data_level = 0
+
+# Restore automatic level selection
+layer.locked_data_level = None
+```
+
+When a level is locked, napari loads the full extent of that level on the currently
+displayed dimensions regardless of zoom or display mode. The lock is automatically 
+reset to `None` when the layer's data is replaced.
+
+This property is available on both `Image` and `Labels` layers.
+
 ## Loading multichannel images
 
 Each channel in a multichannel image can be displayed as an individual layer by