diff --git a/app/coffeescripts/calendar/Calendar.coffee b/app/coffeescripts/calendar/Calendar.coffee
index 3c160809324..d4ec866d10e 100644
--- a/app/coffeescripts/calendar/Calendar.coffee
+++ b/app/coffeescripts/calendar/Calendar.coffee
@@ -652,7 +652,7 @@ define [
     $styleContainer = $('<div />').appendTo('body')
 
     colorizeContexts: =>
-      colors = colorSlicer.getColors(@contextCodes.length, 275)
+      colors = colorSlicer.getColors(@contextCodes.length, 275, {unsafe: !ENV.SETTINGS.use_high_contrast})
       html = for contextCode, index in @contextCodes
         color = colors[index]
         ".group_#{contextCode}{
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 829a0a05301..f7ef5efcb61 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -108,7 +108,8 @@ class ApplicationController < ActionController::Base
         :files_domain => HostUrl.file_host(@domain_root_account || Account.default, request.host_with_port),
         :DOMAIN_ROOT_ACCOUNT_ID => @domain_root_account.try(:global_id),
         :SETTINGS => {
-          open_registration: @domain_root_account.try(:open_registration?)
+          open_registration: @domain_root_account.try(:open_registration?),
+          use_high_contrast: @current_user.try(:prefers_high_contrast?)
         }
       }
       @js_env[:lolcalize] = true if ENV['LOLCALIZE']
diff --git a/bower.json b/bower.json
index b0217c0302f..40f7162df77 100644
--- a/bower.json
+++ b/bower.json
@@ -9,7 +9,7 @@
     "ic-ajax": "~2.0.1",
     "ic-menu": "0.1.11",
     "ic-styled": "1.1.6",
-    "color-slicer": "0.4.0",
+    "color-slicer": "0.8.0",
     "k5uploader": "0.0.3",
     "ember-qunit": "~0.1.7",
     "ic-tabs": "0.1.3",
diff --git a/public/javascripts/bower/color-slicer/.bower.json b/public/javascripts/bower/color-slicer/.bower.json
index 2fb050da26b..06627d90c28 100644
--- a/public/javascripts/bower/color-slicer/.bower.json
+++ b/public/javascripts/bower/color-slicer/.bower.json
@@ -1,6 +1,6 @@
 {
   "name": "color-slicer",
-  "version": "0.7.0",
+  "version": "0.8.0",
   "authors": [
     "Braden Anderson <bluej100@gmail.com>"
   ],
@@ -20,13 +20,13 @@
   ],
   "devDependencies": {},
   "homepage": "https://github.com/instructure/color-slicer",
-  "_release": "0.7.0",
+  "_release": "0.8.0",
   "_resolution": {
     "type": "version",
-    "tag": "v0.7.0",
-    "commit": "74a52e7e6867943ac67f715c54fd8e643e482ae1"
+    "tag": "v0.8.0",
+    "commit": "48b337a8fec31d118f47524a04347a674751de00"
   },
   "_source": "git://github.com/instructure/color-slicer.git",
-  "_target": "~0.7.0",
+  "_target": "0.8.0",
   "_originalSource": "color-slicer"
 }
\ No newline at end of file
diff --git a/public/javascripts/bower/color-slicer/bower.json b/public/javascripts/bower/color-slicer/bower.json
index c385c039bad..0948461efe8 100644
--- a/public/javascripts/bower/color-slicer/bower.json
+++ b/public/javascripts/bower/color-slicer/bower.json
@@ -1,6 +1,6 @@
 {
   "name": "color-slicer",
-  "version": "0.7.0",
+  "version": "0.8.0",
   "authors": [
     "Braden Anderson <bluej100@gmail.com>"
   ],
diff --git a/public/javascripts/bower/color-slicer/dist/color-slicer.js b/public/javascripts/bower/color-slicer/dist/color-slicer.js
index e4e139ee4cf..b069a050ab0 100644
--- a/public/javascripts/bower/color-slicer/dist/color-slicer.js
+++ b/public/javascripts/bower/color-slicer/dist/color-slicer.js
@@ -14,19 +14,26 @@ module.exports = {
     var l, c;
     if (options.l) {
       l = options.l;
-      c = options.c;
     } else if (options.bright) {
       l = 74;
-      c = 41;
+    } else if (options.unsafe) {
+      l = 60;
     } else {
       l = 49;
-      c = 29;
+    }
+    if (options.c) {
+      c = options.c;
+    } else {
+      c = 3 + l / 2;
 
       // vary chroma to roughly match boundary of RGB-expressible colors
-      var delta = 17;
+      var delta = 5 + l/4;
       var most_constrained_hue = 210;
       var hr = (h - most_constrained_hue) / 360 * 2 * Math.PI;
-      c += delta - Math.round(delta * Math.cos(hr));
+      c += Math.floor(delta - delta * Math.cos(hr));
+
+      var overpower = Math.max(Math.floor(160 - (l * 8 / 5)), 0);
+      c = Math.min(c, overpower);
     }
     return [l, c, h]
   },
diff --git a/public/javascripts/bower/color-slicer/dist/example.html b/public/javascripts/bower/color-slicer/dist/example.html
index 190402a8e96..1023bdad8a0 100644
--- a/public/javascripts/bower/color-slicer/dist/example.html
+++ b/public/javascripts/bower/color-slicer/dist/example.html
@@ -21,11 +21,12 @@ var generate = function() {
   var lightness = parseInt(document.getElementById('lightness').value, 10);
   var chroma = parseInt(document.getElementById('chroma').value, 10);
   var bright = document.getElementById('bright').checked;
+  var unsafe = document.getElementById('unsafe').checked;
 
   document.body.style.color = bright ? '#fff' : '#000';
   document.body.style.backgroundColor = bright ? '#000' : '#fff';
 
-  var colors = colorSlicer.getLchColors(count, start, {l: lightness, c: chroma, bright: bright});
+  var colors = colorSlicer.getLchColors(count, start, {l: lightness, c: chroma, bright: bright, unsafe: unsafe});
   var output = document.getElementById('output');
   output.innerHTML = '';
   for (var i = 0; i < colors.length; i++) {
@@ -59,6 +60,7 @@ window.addEventListener('load', function() {
     <div><label>Lightness <input id="lightness" /></label></div>
     <div><label>Chroma <input id="chroma" /></label></div>
     <div><label><input id="bright" type="checkbox" /> Bright</label></div>
+    <div><label><input id="unsafe" type="checkbox" /> Unsafe</label></div>
   </fieldset>
 </form>
 <ol id="output">
diff --git a/public/javascripts/bower/color-slicer/index.js b/public/javascripts/bower/color-slicer/index.js
index 64bf15422ec..2c89c825af7 100644
--- a/public/javascripts/bower/color-slicer/index.js
+++ b/public/javascripts/bower/color-slicer/index.js
@@ -13,19 +13,27 @@ module.exports = {
     var l, c;
     if (options.l) {
       l = options.l;
-      c = options.c;
     } else if (options.bright) {
       l = 74;
-      c = 41;
+    } else if (options.unsafe) {
+      l = 60;
     } else {
       l = 49;
-      c = 29;
+    }
+    if (options.c) {
+      c = options.c;
+    } else {
+      c = 3 + l / 2;
 
-      // vary chroma to roughly match boundary of RGB-expressible colors
-      var delta = 17;
+      // vary chroma to roughly match boundary of darkest RGB-expressible colors
+      var delta = 5 + l/4;
       var most_constrained_hue = 210;
       var hr = (h - most_constrained_hue) / 360 * 2 * Math.PI;
-      c += delta - Math.round(delta * Math.cos(hr));
+      c += Math.floor(delta - delta * Math.cos(hr));
+
+      // constrain chroma by lightest RGB-expressible colors
+      var overpower = Math.max(Math.floor(160 - (l * 8 / 5)), 0);
+      c = Math.min(c, overpower);
     }
     return [l, c, h]
   },
diff --git a/public/javascripts/bower/color-slicer/package.json b/public/javascripts/bower/color-slicer/package.json
index d94a39937b4..08a0f151494 100644
--- a/public/javascripts/bower/color-slicer/package.json
+++ b/public/javascripts/bower/color-slicer/package.json
@@ -1,6 +1,6 @@
 {
   "name": "color-slicer",
-  "version": "0.7.0",
+  "version": "0.8.0",
   "description": "Generate lists of readable text colors.",
   "main": "index.js",
   "scripts": {