diff --git a/ui/TODO.otl b/ui/TODO.otl
index 0beaf650..8a035b44 100755
--- a/ui/TODO.otl
+++ b/ui/TODO.otl
@@ -108,8 +108,34 @@ Roadmap
 	
 
 
-[_] 28% Gen 3 current todo
-	[_] 57% High priority
+[_] 29% Gen 3 current todo
+	[_] 58% High priority
+		[_] BUG: zooming vertical images in single image view results in size jumping...
+		| Reason:
+		| 	This is due to the proportion ratio changing in one step...
+		|
+		| Solution:
+		| 	Make the proportion transition smoothly, at least in two zoom-steps
+		[X] BUG: jumping more than one image in single image view messes up scale...
+		|
+		| Procedure:
+		| 	- load: file:///L:/mnt/hdd13 (photo)/NTFS2/media/img/my/work/- 20131122Y.001/DCIM/preview (RAW)/
+		| 	- go to single image mode
+		| 	- press 2
+		| 	- go to end
+		| 	- press [ until a long jump between vertical and horizontal pics
+		|
+		| Effect:
+		| 	- the size of the images will change
+		|
+		| Solution:
+		| 	moved the proportions mode switch to preFittingImages handler
+		|
+		| Side-effect:
+		| 	vertical images, in horizontal viewer, and vice-versa jump 
+		| 	in size a bit when zooming past the threshold...
+		| 	the amount of "jump" depends on viewer proportions vs. image
+		| 	proportions...
 		[X] BUG: appear to be leaking memory on very large sets of images (>8K)
 		| don't remember it before, so it might be due to the new 
 		| loadImagesAround(..)
@@ -266,11 +292,11 @@ Roadmap
 		| 	- open/history/...
 		| 	- sort
 		| 	- export
-		[_] 50% mark-based operations
-			[_] 50% cropping selection
+		[_] 55% mark-based operations
+			[_] 75% cropping selection
 				[X] marked
 				[X] ribbon
-				[_] by tag/collection
+				[X] by tag/collection
 				[_] by group
 			[X] shift up/down
 			[X] tag
diff --git a/ui/data.js b/ui/data.js
index 182a87ad..3ef4b9c8 100755
--- a/ui/data.js
+++ b/ui/data.js
@@ -660,7 +660,6 @@ function makeGIDBeforeGetterFromList(get_list, restrict_to_ribbon){
 		if(list.length == 0){
 			return null
 		}
-		console.log('>>>>', ribbon)
 		gid = gid == null ? getImageGID(null, ribbon) : gid
 		var prev
 
@@ -2100,6 +2099,17 @@ function setupData(viewer){
 			rollImages(gr.length, ribbon)
 		})
 
+		.on('preFittingImages', function(evt, n){
+			// update proportions...
+			if(CONFIG.proportions_ratio_threshold != null 
+					&& toggleSingleImageMode('?') == 'on'){
+				if(n <= CONFIG.proportions_ratio_threshold){
+					toggleImageProportions('fit-viewer')
+				} else {
+					toggleImageProportions('none')
+				}
+			}
+		})
 		.on('fittingImages', function(evt, n){
 			//console.log('!!!! fittingImages')
 			// load correct amount of images in each ribbon!!!
@@ -2137,24 +2147,6 @@ function setupData(viewer){
 				UI_STATE['ribbon-mode-screen-images'] = n
 			}
 
-			// update proportions...
-			if(CONFIG.proportions_ratio_threshold != null 
-					&& toggleSingleImageMode('?') == 'on'){
-
-				var h = getVisibleImageSize('height')
-				var w = getVisibleImageSize('width')
-				var H = $('.viewer').innerHeight()
-				var W = $('.viewer').innerWidth()
-
-				var m = Math.min(W/w, H/h)
-
-				if(m < CONFIG.proportions_ratio_threshold){
-					toggleImageProportions('fit-viewer')
-				} else {
-					toggleImageProportions('none')
-				}
-			}
-
 			// update size classes...
 			// XXX make thresholds global...
 			if(n <= 2.5){
diff --git a/ui/modes.js b/ui/modes.js
index 6ef61352..0aee0a3f 100755
--- a/ui/modes.js
+++ b/ui/modes.js
@@ -325,18 +325,57 @@ var toggleInlineImageInfo = createCSSClassToggler(
 		})
 
 
+function setImageProportions(image, mode){
+	var h = image.outerHeight(true)
+	var w = image.outerWidth(true)
+	mode = mode == null ? toggleImageProportions('?') : 'square'
+	mode = mode == 'fit-viewer' ? 'viewer' : 'squzre' 
+
+	if(mode == 'viewer'){
+		var viewer = $('.viewer')
+		var W = viewer.innerWidth()
+		var H = viewer.innerHeight()
+
+		if(W > H){
+			image.css('width', W * h/H)
+		} else {
+			image.css('height', H * w/W)
+		}
+
+		// account for rotation...
+		correctImageProportionsForRotation(image)
+		centerView(null, 'css')
+
+	} else {
+		var size = Math.min(w, h)
+		image.css({
+			width: size,
+			height: size
+		})
+
+		// account for rotation...
+		correctImageProportionsForRotation(image)
+		centerView(null, 'css')
+	}
+
+	return image
+}
+
+
 var toggleImageProportions = createCSSClassToggler(
 		'.viewer',
 		[
 			'none',
 			'fit-viewer'
 		],
+		/* XXX do we need this???
 		function(action){
 			// prevent reentering...
 			if(action == toggleImageProportions('?')){
 				return false
 			}
 		},
+		*/
 		function(action){
 			var image = $('.image')
 			var h = image.outerHeight(true)
@@ -345,16 +384,22 @@ var toggleImageProportions = createCSSClassToggler(
 			// viewer proportions...
 			// XXX going into here twice for a rotated 90/270 image will 
 			// 		set it back to square...
-			// 		...can't even begin to imagine what can affect this!
+			// 		XXX can't reproduce this error...
 			if(action == 'fit-viewer'){
 				var viewer = $('.viewer')
 				var W = viewer.innerWidth()
 				var H = viewer.innerHeight()
 
 				if(W > H){
-					image.css('width', W * h/H)
+					image.css({
+						width: W * h/H,
+						height: '',
+					})
 				} else {
-					image.css('height', H * w/W)
+					image.css({
+						width: '',
+						height: H * w/W,
+					})
 				}
 
 				// account for rotation...
diff --git a/ui/ribbons.js b/ui/ribbons.js
index 69201825..7e2fc45e 100755
--- a/ui/ribbons.js
+++ b/ui/ribbons.js
@@ -225,8 +225,8 @@ function getVisibleImageSize(dim){
 
 
 // Return the number of images that can fit to viewer width...
-function getScreenWidthInImages(size){
-	size = size == null ? getVisibleImageSize() : size
+function getScreenWidthInImages(size, dim){
+	size = size == null ? getVisibleImageSize(dim) : size
 	return $('.viewer').innerWidth() / size
 }