diff --git a/ChangeLog b/ChangeLog
index 8d511584..906693cb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,6 +2,9 @@
 - configure fails for requested but unmet dependencies [remicollet]
 - add support for another quantiser [DarthSim]
 
+26/11/21 started 8.12.2
+- make exif resuint optional and default to inch
+
 21/11/21 started 8.12.1
 - fix insert [chregu]
 
diff --git a/libvips/foreign/exif.c b/libvips/foreign/exif.c
index 12e40292..e7d08d6f 100644
--- a/libvips/foreign/exif.c
+++ b/libvips/foreign/exif.c
@@ -416,11 +416,15 @@ vips_image_resolution_from_exif( VipsImage *image, ExifData *ed )
 	 */
 	if( vips_exif_entry_get_double( ed, 0, EXIF_TAG_X_RESOLUTION, &xres ) ||
 		vips_exif_entry_get_double( ed, 
-			0, EXIF_TAG_Y_RESOLUTION, &yres ) ||
-		vips_exif_entry_get_int( ed, 
-			0, EXIF_TAG_RESOLUTION_UNIT, &unit ) ) 
+			0, EXIF_TAG_Y_RESOLUTION, &yres ) )
 		return( -1 );
 
+	/* resuint is optional and defaults to inch.
+	 */
+	unit = 2;
+	(void) vips_exif_entry_get_int( ed, 
+		0, EXIF_TAG_RESOLUTION_UNIT, &unit );
+
 #ifdef DEBUG
 	printf( "vips_image_resolution_from_exif: seen exif tags "
 		"xres = %g, yres = %g, unit = %d\n", xres, yres, unit );