diff --git a/ChangeLog b/ChangeLog
index 4358e66b..278bc7a8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -12,7 +12,8 @@
   im_rint(), im_equal*(), im_notequal*(), im_less*(), im_lesseq*(), im_more*(),
   im_moreeq*(), im_remainder*(), im_and*(), im_or*(), im_eor*(), im_shift*(),
   im_pow*(), im_exp*(), im_ifthenelse(), im_blend(), im_c2amph(), im_c2rect(),
-  im_bandmean(), im_c2real(), im_c2imag(), im_ri2c()
+  im_bandmean(), im_c2real(), im_c2imag(), im_ri2c(), im_jpeg*2vips(), 
+  im_vips2jpeg*(), im_tiff2vips(), im_vips2tiff(), 
   redone as classes
 - added argument priorites to help control arg ordering
 - generate has a 'stop' param to signal successful early termination
diff --git a/TODO b/TODO
index 0d3bc8d8..48d8211f 100644
--- a/TODO
+++ b/TODO
@@ -1,10 +1,6 @@
 - still some size_t that should be guint64, search for all use of 
   VIPS_IMAGE_SIZEOF_IMAGE(), vips__parse_size()
 
-- some mysterious error in tilecahce for new-style openslide read
-
-
-
 
 
 - how about
@@ -18,12 +14,6 @@
 
 
 
-- add ".ndpi" to openslide suffs? though we don't really use suffs for loaders
-
-- check lazy load hint bug in format-hacking branch
-
-- everywhere must set dhint in header load
-
 - openslide sets a g_log() handler, argh, must just set temp
 
 - make an argb coding type, add to nip2 and known coding
diff --git a/libvips/conversion/tilecache.c b/libvips/conversion/tilecache.c
index bd0f7789..1f277396 100644
--- a/libvips/conversion/tilecache.c
+++ b/libvips/conversion/tilecache.c
@@ -207,9 +207,7 @@ tile_fill( Tile *tile, VipsRegion *in )
 {
 	VipsRect area;
 
-#ifdef DEBUG
-	printf( "im_tile_cache: filling tile %d x %d\n", tile->x, tile->y );
-#endif /*DEBUG*/
+	VIPS_DEBUG_MSG( "tilecache: filling tile %d x %d\n", tile->x, tile->y );
 
 	area.left = tile->x;
 	area.top = tile->y;
@@ -270,9 +268,7 @@ tile_find( VipsTileCache *cache, VipsRegion *in, int x, int y )
 
 	g_assert( tile );
 
-#ifdef DEBUG
-	printf( "im_tile_cache: reusing tile %d x %d\n", tile->x, tile->y );
-#endif /*DEBUG*/
+	VIPS_DEBUG_MSG( "tilecache: reusing tile %d x %d\n", tile->x, tile->y );
 
 	if( tile_move( tile, x, y ) ||
 		tile_fill( tile, in ) )
@@ -360,6 +356,8 @@ vips_tile_cache_build( VipsObject *object )
 	VipsConversion *conversion = VIPS_CONVERSION( object );
 	VipsTileCache *cache = (VipsTileCache *) object;
 
+	VIPS_DEBUG_MSG( "vips_tile_cache_build\n" );
+
 	if( VIPS_OBJECT_CLASS( vips_tile_cache_parent_class )->build( object ) )
 		return( -1 );
 
@@ -457,7 +455,7 @@ vips_tile_cache_init( VipsTileCache *cache )
  * will cache up to 1,000 tiles.
  *
  * This is a lower-level operation than vips_image_cache() since it does no 
- * subdivision and it single-threads it's callee. It is suitable for caching 
+ * subdivision and it single-threads its callee. It is suitable for caching 
  * the output of operations like exr2vips() on tiled images.
  *
  * See also: vips_image_cache().
diff --git a/libvips/foreign/Makefile.am b/libvips/foreign/Makefile.am
index c376ff32..4931aa0d 100644
--- a/libvips/foreign/Makefile.am
+++ b/libvips/foreign/Makefile.am
@@ -1,8 +1,8 @@
 noinst_LTLIBRARIES = libforeign.la
 
 libforeign_la_SOURCES = \
-	vipsopenslide.h \
-	vipsopenslide.c \
+	openslide2vips.h \
+	openslide2vips.c \
 	openslideload.c \
 	tiff.h \
 	vips2tiff.c \
diff --git a/libvips/foreign/jpeg2vips.c b/libvips/foreign/jpeg2vips.c
index ce1c8ddf..041a648e 100644
--- a/libvips/foreign/jpeg2vips.c
+++ b/libvips/foreign/jpeg2vips.c
@@ -573,6 +573,10 @@ read_jpeg_header( struct jpeg_decompress_struct *cinfo,
 		interpretation,
 		1.0, 1.0 );
 
+	/* Best for us, probably.
+	 */
+	vips_demand_hint( out, VIPS_DEMAND_STYLE_FATSTRIP, NULL );
+
 	/* Interlaced jpegs need lots of memory to read, so our caller needs
 	 * to know.
 	 */
diff --git a/libvips/foreign/vipsopenslide.c b/libvips/foreign/openslide2vips.c
similarity index 88%
rename from libvips/foreign/vipsopenslide.c
rename to libvips/foreign/openslide2vips.c
index a951f244..04ef3aa4 100644
--- a/libvips/foreign/vipsopenslide.c
+++ b/libvips/foreign/openslide2vips.c
@@ -65,7 +65,7 @@
 
 #include <openslide.h>
 
-#include "vipsopenslide.h"
+#include "openslide2vips.h"
 
 /* We run our own tile cache. The OpenSlide one can't always keep enough for a
  * complete lines of pixels.
@@ -90,21 +90,19 @@ vips__openslide_isslide( const char *filename )
 	const char *vendor;
 	int ok;
 
-	ok = 1;
-	osr = openslide_open( filename );
-	if( osr != NULL ) {
-		/* If this is a generic tiled TIFF image, decline to support
-		 * it, since im_tiff2vips can do better.
+	ok = 0;
+	if( (osr = openslide_open( filename )) ) {
+		/* Generic tiled tiff images can be opened by openslide as
+		 * well. Only offer to load this file if it's not a generic
+		 * tiff since we want vips_tiffload() to handle these.
 		 */
 		vendor = openslide_get_property_value( osr,
 			OPENSLIDE_PROPERTY_NAME_VENDOR );
-		if( vendor == NULL ||
-			strcmp( vendor, "generic-tiff" ) == 0 )
-			ok = 0;
+		if( vendor &&
+			strcmp( vendor, "generic-tiff" ) != 0 )
+			ok = 1;
 		openslide_close( osr );
 	} 
-	else 
-		ok = 0;
 
 	VIPS_DEBUG_MSG( "vips__openslide_isslide: %s - %d\n", filename, ok );
 
@@ -128,7 +126,7 @@ check_associated_image( openslide_t *osr, const char *name )
 		if( strcmp( *associated, name ) == 0 )
 			return( 0 );
 
-	vips_error( "im_openslide2vips", 
+	vips_error( "openslide2vips", 
 		"%s", _( "invalid associated image name" ) );
 
 	return( -1 );
@@ -153,21 +151,21 @@ readslide_new( const char *filename, VipsImage *out,
 
 	rslide->osr = openslide_open( filename );
 	if( rslide->osr == NULL ) {
-		vips_error( "im_openslide2vips", 
+		vips_error( "openslide2vips", 
 			"%s", _( "failure opening slide" ) );
 		return( NULL );
 	}
 
 	if( layer < 0 || 
 		layer >= openslide_get_layer_count( rslide->osr ) ) {
-		vips_error( "im_openslide2vips",
+		vips_error( "openslide2vips",
 			"%s", _( "invalid slide layer" ) );
 		return( NULL );
 	}
 
 	if( associated &&
 		check_associated_image( rslide->osr, associated ) )
-			return( NULL );
+		return( NULL );
 
 	if( associated ) {
 		openslide_get_associated_image_dimensions( rslide->osr,
@@ -190,24 +188,24 @@ readslide_new( const char *filename, VipsImage *out,
 	background = openslide_get_property_value( rslide->osr,
 		OPENSLIDE_PROPERTY_NAME_BACKGROUND_COLOR );
 	if( background != NULL )
-		im_meta_set_int( out, 
+		vips_image_set_int( out, 
 			"background-rgb", strtoul( background, NULL, 16 ) );
 	else
-		im_meta_set_int( out, "background-rgb", 0xffffff );
+		vips_image_set_int( out, "background-rgb", 0xffffff );
 
 	if( w < 0 || h < 0 || rslide->downsample < 0 ) {
-		vips_error( "im_openslide2vips", _( "getting dimensions: %s" ),
+		vips_error( "openslide2vips", _( "getting dimensions: %s" ),
 			openslide_get_error( rslide->osr ) );
 		return( NULL );
 	}
 	if( w > INT_MAX || 
 		h > INT_MAX ) {
-		vips_error( "im_openslide2vips",
+		vips_error( "openslide2vips",
 			"%s", _( "image dimensions overflow int" ) );
 		return( NULL );
 	}
 
-	vips_image_init_fields( out, (int) w, (int) h, 4, VIPS_FORMAT_UCHAR,
+	vips_image_init_fields( out, w, h, 4, VIPS_FORMAT_UCHAR,
 		VIPS_CODING_NONE, VIPS_INTERPRETATION_RGB, 1.0, 1.0 );
 
 	for( properties = openslide_get_property_names( rslide->osr );
@@ -245,11 +243,11 @@ vips__openslide_generate( VipsRegion *out,
 	const char *error;
 	int x, y;
 
-	VIPS_DEBUG_MSG( "fill_region: %dx%d @ %dx%d\n",
+	VIPS_DEBUG_MSG( "vips__openslide_generate: %dx%d @ %dx%d\n",
 		r->width, r->height, r->left, r->top );
 
 	/* Fill in tile-sized chunks. Some versions of OpenSlide can fail for
-	 * very large dimensions.
+	 * very large requests.
 	 */
 	for( y = 0; y < r->height; y += TILE_HEIGHT ) 
 		for( x = 0; x < r->width; x += TILE_WIDTH ) {
@@ -267,7 +265,7 @@ vips__openslide_generate( VipsRegion *out,
 
 	error = openslide_get_error( rslide->osr );
 	if( error ) {
-		vips_error( "im_openslide2vips", 
+		vips_error( "openslide2vips", 
 			_( "reading region: %s" ), error );
 
 		return( -1 );
@@ -286,9 +284,9 @@ vips__openslide_read( const char *filename, VipsImage *out, int layer )
 	VIPS_DEBUG_MSG( "vips__openslide_read: %s %d\n", 
 		filename, layer );
 
-	/* Tile cache: keep enough for two complete rows of tiles.
-	 * This lets us do (smallish) area ops, like im_conv(), while
-	 * still only hitting each tile once.
+	/* Tile cache: keep enough for two complete rows of tiles. OpenSlide
+	 * has its own tile cache, but it's not large enough for a complete
+	 * scan line.
 	 */
 	raw = vips_image_new();
 	vips_object_local( out, raw );
@@ -307,7 +305,7 @@ vips__openslide_read( const char *filename, VipsImage *out, int layer )
 	if( vips_tilecache( raw, &t, 
 		"tile_width", TILE_WIDTH, 
 		"tile_height", TILE_WIDTH,
-		"max_tiles", 1.5 * (1 + raw->Xsize / TILE_WIDTH),
+		"max_tiles", (int) (1.5 * (1 + raw->Xsize / TILE_WIDTH)),
 		NULL ) ) 
 		return( -1 );
 	if( vips_image_write( t, out ) ) {
@@ -344,7 +342,7 @@ vips__openslide_read_associated( const char *filename, VipsImage *out,
 		(uint32_t *) VIPS_IMAGE_ADDR( raw, 0, 0 ) );
 	error = openslide_get_error( rslide->osr );
 	if( error ) {
-		vips_error( "im_openslide2vips",
+		vips_error( "openslide2vips",
 			_( "reading associated image: %s" ), error );
 		return( -1 );
 	}
diff --git a/libvips/foreign/vipsopenslide.h b/libvips/foreign/openslide2vips.h
similarity index 93%
rename from libvips/foreign/vipsopenslide.h
rename to libvips/foreign/openslide2vips.h
index b66b121d..8fc6cdec 100644
--- a/libvips/foreign/vipsopenslide.h
+++ b/libvips/foreign/openslide2vips.h
@@ -27,8 +27,8 @@
 
  */
 
-#ifndef VIPS_OPENSLIDE_H
-#define VIPS_OPENSLIDE_H
+#ifndef VIPS_OPENSLIDE2VIPS_H
+#define VIPS_OPENSLIDE2VIPS_H
 
 #ifdef __cplusplus
 extern "C" {
@@ -46,4 +46,4 @@ int vips__openslide_read_associated( const char *filename, VipsImage *out,
 }
 #endif /*__cplusplus*/
 
-#endif /*VIPS_OPENSLIDE_H*/
+#endif /*VIPS_OPENSLIDE2VIPS_H*/
diff --git a/libvips/foreign/openslideload.c b/libvips/foreign/openslideload.c
index 17ec670b..7ad03ade 100644
--- a/libvips/foreign/openslideload.c
+++ b/libvips/foreign/openslideload.c
@@ -47,7 +47,7 @@
 #include <vips/buf.h>
 #include <vips/internal.h>
 
-#include "vipsopenslide.h"
+#include "openslide2vips.h"
 
 typedef struct _VipsForeignLoadOpenslide {
 	VipsForeignLoad parent_object;
diff --git a/libvips/include/vips/foreign.h b/libvips/include/vips/foreign.h
index aa1bf961..6f03b8d5 100644
--- a/libvips/include/vips/foreign.h
+++ b/libvips/include/vips/foreign.h
@@ -146,6 +146,9 @@ typedef struct _VipsForeignLoadClass {
 	/* Set the header fields in @out from @filename. If you can read the 
 	 * whole image as well with no performance cost (as with vipsload),
 	 * leave ->load() NULL and only @header will be used.
+	 *
+	 * ->header() needs to set the dhint on the image .. otherwise you get 
+	 * the default SMALLTILE.
 	 */
 	int (*header)( VipsForeignLoad * );
 
diff --git a/libvips/iofuncs/operation.c b/libvips/iofuncs/operation.c
index 782d2327..8f65080d 100644
--- a/libvips/iofuncs/operation.c
+++ b/libvips/iofuncs/operation.c
@@ -28,8 +28,8 @@
  */
 
 /*
- */
 #define VIPS_DEBUG
+ */
 
 #ifdef HAVE_CONFIG_H
 #include <config.h>