diff --git a/ChangeLog b/ChangeLog
index d0f76e41..74ec9b80 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+28/6/13 started 7.34.1
+- fix morphological operators on non-uchar images
+
 7/6/13 started 7.34.0
 - version bump
 - oops, VImage.PIL_mode_from_vips() failed for CMYK, thanks Alessandro
diff --git a/TODO b/TODO
index d6aef312..aa6d994c 100644
--- a/TODO
+++ b/TODO
@@ -1,3 +1,6 @@
+- 3-way dilate on a float image seems to be broken
+
+
 - object construction is threadsafe, but class construction is not
 
   https://github.com/jcupitt/libvips/issues/64
diff --git a/configure.ac b/configure.ac
index eecf9c7f..18ba33c3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2,7 +2,7 @@
 
 # also update the version number in the m4 macros below
 
-AC_INIT([vips], [7.34.0], [vipsip@jiscmail.ac.uk])
+AC_INIT([vips], [7.34.1], [vipsip@jiscmail.ac.uk])
 # required for gobject-introspection
 AC_PREREQ(2.62)
 
@@ -17,7 +17,7 @@ AC_CONFIG_MACRO_DIR([m4])
 # user-visible library versioning
 m4_define([vips_major_version], [7])
 m4_define([vips_minor_version], [34])
-m4_define([vips_micro_version], [0])
+m4_define([vips_micro_version], [1])
 m4_define([vips_version],
           [vips_major_version.vips_minor_version.vips_micro_version])
 
@@ -37,7 +37,7 @@ VIPS_VERSION_STRING=$VIPS_VERSION-`date`
 #   binary interface changes not backwards compatible?: reset age to 0
 
 LIBRARY_CURRENT=34
-LIBRARY_REVISION=3
+LIBRARY_REVISION=4
 LIBRARY_AGE=3
 
 # patched into include/vips/version.h
diff --git a/libvips/morphology/morphology.c b/libvips/morphology/morphology.c
index 6b13c1b9..9882e6fc 100644
--- a/libvips/morphology/morphology.c
+++ b/libvips/morphology/morphology.c
@@ -19,6 +19,8 @@
  * 7/11/10
  * 	- gtk-doc
  * 	- do (!=0) to make uchar, if we're not given uchar
+ * 28/6/13
+ * 	- oops, fix !=0 code
  */
 
 /*
@@ -714,11 +716,12 @@ morphology( IMAGE *in, IMAGE *out, INTMASK *mask, MorphOp op )
 	/* Prepare output. Consider a 7x7 mask and a 7x7 image --- the output
 	 * would be 1x1.
 	 */
-	if( im_cp_desc( out, in ) )
+	if( im_cp_desc( morph->out, morph->in ) )
 		return( -1 );
-	out->Xsize -= mask->xsize - 1;
-	out->Ysize -= mask->ysize - 1;
-	if( out->Xsize <= 0 || out->Ysize <= 0 ) {
+	morph->out->Xsize -= morph->mask->xsize - 1;
+	morph->out->Ysize -= morph->mask->ysize - 1;
+	if( morph->out->Xsize <= 0 || 
+		morph->out->Ysize <= 0 ) {
 		im_error( "morph", "%s", _( "image too small for mask" ) );
 		return( -1 );
 	}
@@ -730,7 +733,7 @@ morphology( IMAGE *in, IMAGE *out, INTMASK *mask, MorphOp op )
 		printf( "morph_vector_gen: %d passes\n", morph->n_pass );
 #endif /*DEBUG*/
 	}
-	else if( op == DILATE )
+	else if( morph->op == DILATE )
 		generate = dilate_gen;
 	else
 		generate = erode_gen;
@@ -738,13 +741,13 @@ morphology( IMAGE *in, IMAGE *out, INTMASK *mask, MorphOp op )
 	/* Set demand hints. FATSTRIP is good for us, as THINSTRIP will cause
 	 * too many recalculations on overlaps.
 	 */
-	if( im_demand_hint( out, IM_FATSTRIP, in, NULL ) ||
-		im_generate( out, 
-			morph_start, generate, morph_stop, in, morph ) )
+	if( im_demand_hint( morph->out, IM_FATSTRIP, morph->in, NULL ) ||
+		im_generate( morph->out, 
+			morph_start, generate, morph_stop, morph->in, morph ) )
 		return( -1 );
 
-	out->Xoffset = -mask->xsize / 2;
-	out->Yoffset = -mask->ysize / 2;
+	morph->out->Xoffset = -morph->mask->xsize / 2;
+	morph->out->Yoffset = -morph->mask->ysize / 2;
 
 	return( 0 );
 }