diff --git a/src/plots/cartesian/constraints.js b/src/plots/cartesian/constraints.js
index 249154fa6a4..895c9fffccb 100644
--- a/src/plots/cartesian/constraints.js
+++ b/src/plots/cartesian/constraints.js
@@ -20,6 +20,7 @@ var FROM_BL = require('../../constants/alignment').FROM_BL;
 exports.handleConstraintDefaults = function(containerIn, containerOut, coerce, opts) {
     var allAxisIds = opts.allAxisIds;
     var layoutOut = opts.layoutOut;
+    var scaleanchorDflt = opts.scaleanchorDflt;
     var constraintGroups = layoutOut._axisConstraintGroups;
     var matchGroups = layoutOut._axisMatchGroups;
     var axId = containerOut._id;
@@ -55,14 +56,17 @@ exports.handleConstraintDefaults = function(containerIn, containerOut, coerce, o
     // 'matches' wins over 'scaleanchor' (for now)
     var scaleanchor, scaleOpts;
 
-    if(!matches && (containerIn.scaleanchor || opts.scaleanchorDflt) && !(containerOut.fixedrange && constrain !== 'domain')) {
+    if(!matches &&
+       !(containerOut.fixedrange && constrain !== 'domain') &&
+       (containerIn.scaleanchor || scaleanchorDflt)
+     ) {
         scaleOpts = getConstraintOpts(constraintGroups, thisID, allAxisIds, layoutOut, constrain);
         scaleanchor = Lib.coerce(containerIn, containerOut, {
             scaleanchor: {
                 valType: 'enumerated',
                 values: scaleOpts.linkableAxes || []
             }
-        }, 'scaleanchor', opts.scaleanchorDflt);
+        }, 'scaleanchor', scaleanchorDflt);
     }
 
     if(matches) {
diff --git a/src/plots/cartesian/layout_defaults.js b/src/plots/cartesian/layout_defaults.js
index cce05296e94..6063f6f9641 100644
--- a/src/plots/cartesian/layout_defaults.js
+++ b/src/plots/cartesian/layout_defaults.js
@@ -82,8 +82,10 @@ module.exports = function supplyLayoutDefaults(layoutIn, layoutOut, fullData) {
             }
             yaMustNotScaleanchor[yaName] = true;
         } else if(trace.type === 'image') {
-            if(yaName) yaMayReverse[yaName] = true;
-            if(yaName) yaMayScaleanchor[yaName] = true;
+            if(yaName) {
+                yaMayReverse[yaName] = true;
+                yaMayScaleanchor[yaName] = true;
+            }
         } else {
             if(yaName) {
                 yaMustDisplay[yaName] = true;
diff --git a/test/image/baselines/image_axis_type.png b/test/image/baselines/image_axis_type.png
index 09750ff77e8..f7bf648fd58 100644
Binary files a/test/image/baselines/image_axis_type.png and b/test/image/baselines/image_axis_type.png differ
diff --git a/test/image/baselines/image_colormodel.png b/test/image/baselines/image_colormodel.png
index 3e00f14cc1c..576268e60b7 100644
Binary files a/test/image/baselines/image_colormodel.png and b/test/image/baselines/image_colormodel.png differ
diff --git a/test/image/baselines/image_opacity.png b/test/image/baselines/image_opacity.png
index d24e9a08da9..4875b3d8e4a 100644
Binary files a/test/image/baselines/image_opacity.png and b/test/image/baselines/image_opacity.png differ
diff --git a/test/image/baselines/image_with_gaps.png b/test/image/baselines/image_with_gaps.png
index 658bf22470d..d8b21fadd4c 100644
Binary files a/test/image/baselines/image_with_gaps.png and b/test/image/baselines/image_with_gaps.png differ
diff --git a/test/image/baselines/image_zmin_zmax.png b/test/image/baselines/image_zmin_zmax.png
index d286b9a9f6e..44c7b816113 100644
Binary files a/test/image/baselines/image_zmin_zmax.png and b/test/image/baselines/image_zmin_zmax.png differ
diff --git a/test/image/mocks/image_axis_type.json b/test/image/mocks/image_axis_type.json
index 46726d0a086..85c021927b2 100644
--- a/test/image/mocks/image_axis_type.json
+++ b/test/image/mocks/image_axis_type.json
@@ -28,7 +28,6 @@
       "width": 400, "height": 600, "title": {"text": "Image on categorical and log axes"},
       "grid": {"rows": 2, "columns": 1, "pattern": "independent"},
       "xaxis2": {"type": "log"},
-      "yaxis": {"scaleanchor": null},
-      "yaxis2": {"type": "log", "scaleanchor": null}
+      "yaxis2": {"type": "log"}
     }
 }
diff --git a/test/image/mocks/image_colormodel.json b/test/image/mocks/image_colormodel.json
index b611d7a9456..4aa9bd7084a 100644
--- a/test/image/mocks/image_colormodel.json
+++ b/test/image/mocks/image_colormodel.json
@@ -2,12 +2,14 @@
   "data": [{
     "type": "image",
     "colormodel": "rgb",
-    "dy": 10,
+    "hoverinfo": "all",
+    "dy": 1,
     "dx": 0.5,
     "z": [[[255, 0, 0], [0, 255, 0], [0, 0, 255]]]
   }, {
     "type": "image",
     "colormodel": "hsl",
+    "hoverinfo": "all",
     "z": [
       [[0, 33, 50], [0, 66, 50], [0, 100, 50]],
       [[90, 33, 50], [90, 66, 50], [90, 100, 50]],
@@ -18,9 +20,7 @@
     "yaxis": "y2"
   }],
   "layout": {
-    "grid": {"rows": 2, "columns": 1, "pattern": "independent"},
-    "yaxis": {"scaleanchor": null},
-    "yaxis2": {"scaleanchor": null},
+    "grid": {"rows": 1, "columns": 2, "pattern": "independent"},
     "width": 600,
     "height": 400
   }
diff --git a/test/image/mocks/image_opacity.json b/test/image/mocks/image_opacity.json
index 635300d0417..c4d5153bc76 100644
--- a/test/image/mocks/image_opacity.json
+++ b/test/image/mocks/image_opacity.json
@@ -5,7 +5,6 @@
     "z": [[[255, 0, 0], [0, 255, 0], [0, 0, 255]]]
     }],
     "layout": {
-      "yaxis": {"scaleanchor": null},
       "width": 400, "height": 400,
       "title": {
         "text": "image with opacity 0.1"
diff --git a/test/image/mocks/image_with_gaps.json b/test/image/mocks/image_with_gaps.json
index 0f2770a7992..cd9e9950a1c 100644
--- a/test/image/mocks/image_with_gaps.json
+++ b/test/image/mocks/image_with_gaps.json
@@ -9,7 +9,6 @@
     "zmax": [1, 1, 1]
   }],
   "layout": {
-    "yaxis": {"scaleanchor": null},
     "width": 400, "height": 400, "title": {"text": "Image with missing pixels"}
   }
 }
diff --git a/test/image/mocks/image_zmin_zmax.json b/test/image/mocks/image_zmin_zmax.json
index 5880cc3191f..8dd9a252ebf 100644
--- a/test/image/mocks/image_zmin_zmax.json
+++ b/test/image/mocks/image_zmin_zmax.json
@@ -60,14 +60,6 @@
   "layout": {
     "width": 400,
     "height": 800,
-    "yaxis": {"scaleanchor": null},
-    "yaxis2": {"scaleanchor": null},
-    "yaxis3": {"scaleanchor": null},
-    "yaxis4": {"scaleanchor": null},
-    "yaxis5": {"scaleanchor": null},
-    "yaxis6": {"scaleanchor": null},
-    "yaxis7": {"scaleanchor": null},
-    "yaxis8": {"scaleanchor": null},
     "grid": {
       "rows": 4,
       "columns": 2,
diff --git a/test/jasmine/tests/image_test.js b/test/jasmine/tests/image_test.js
index 8d7ae829410..93045a1831e 100644
--- a/test/jasmine/tests/image_test.js
+++ b/test/jasmine/tests/image_test.js
@@ -500,10 +500,10 @@ describe('image hover:', function() {
                 zmax: [1, 1, 1],
                 text: [['A', 'B', 'C'], ['D', 'E', 'F']],
                 hovertemplate: '%{text}<extra></extra>'
-            }], layout: {width: 400, height: 400, yaxis: {scaleanchor: null}}};
+            }], layout: {width: 400, height: 400}};
 
             Plotly.newPlot(gd, mockCopy)
-            .then(function() {_hover(140, 200);})
+            .then(function() {_hover(140, 180);})
             .then(function() {
                 assertHoverLabelContent({
                     nums: 'E',