Images can be converted instead

Author: radarhere

docs/deprecations.rst

@@ -200,7 +200,12 @@ Saving I mode images as PNG
 
 In order to fit the 32 bits of I mode images into PNG, when PNG images can only contain
 at most 16 bits for a channel, Pillow has been clipping the values. Rather than quietly
-changing the data, this is now deprecated.
+changing the data, this is now deprecated. Instead, the image can be converted to
+another mode before saving::
+
+    from PIL import Image
+    im = Image.new("I", (1, 1))
+    im.convert("I;16").save("out.png")
 
 Removed features
 ----------------

docs/releasenotes/11.3.0.rst

@@ -28,7 +28,12 @@ Saving I mode images as PNG
 
 In order to fit the 32 bits of I mode images into PNG, when PNG images can only contain
 at most 16 bits for a channel, Pillow has been clipping the values. Rather than quietly
-changing the data, this is now deprecated.
+changing the data, this is now deprecated. Instead, the image can be converted to
+another mode before saving::
+
+    from PIL import Image
+    im = Image.new("I", (1, 1))
+    im.convert("I;16").save("out.png")
 
 API changes
 ===========