diff --git a/src/components/colorscale/extract_scale.js b/src/components/colorscale/extract_scale.js
new file mode 100644
index 00000000000..845b0fde95d
--- /dev/null
+++ b/src/components/colorscale/extract_scale.js
@@ -0,0 +1,35 @@
+/**
+* Copyright 2012-2016, Plotly, Inc.
+* All rights reserved.
+*
+* This source code is licensed under the MIT license found in the
+* LICENSE file in the root directory of this source tree.
+*/
+
+
+'use strict';
+
+/**
+ * Extract colorscale into numeric domain and color range.
+ *
+ * @param {array} scl colorscale array of arrays
+ * @param {number} cmin minimum color value (used to clamp scale)
+ * @param {number} cmax maximum color value (used to clamp scale)
+ */
+module.exports = function extractScale(scl, cmin, cmax) {
+    var N = scl.length,
+        domain = new Array(N),
+        range = new Array(N);
+
+    for(var i = 0; i < N; i++) {
+        var si = scl[i];
+
+        domain[i] = cmin + si[0] * (cmax - cmin);
+        range[i] = si[1];
+    }
+
+    return {
+        domain: domain,
+        range: range
+    };
+};
diff --git a/src/components/colorscale/index.js b/src/components/colorscale/index.js
index 6da3ccc4532..de016dc8d4f 100644
--- a/src/components/colorscale/index.js
+++ b/src/components/colorscale/index.js
@@ -27,4 +27,6 @@ exports.getScale = require('./get_scale');
 
 exports.flipScale = require('./flip_scale');
 
-exports.makeScaleFunction = require('./make_scale_function');
+exports.extractScale = require('./extract_scale');
+
+exports.makeColorScaleFunc = require('./make_color_scale_func');
diff --git a/src/components/colorscale/make_color_scale_func.js b/src/components/colorscale/make_color_scale_func.js
new file mode 100644
index 00000000000..984a04559b5
--- /dev/null
+++ b/src/components/colorscale/make_color_scale_func.js
@@ -0,0 +1,94 @@
+/**
+* Copyright 2012-2016, Plotly, Inc.
+* All rights reserved.
+*
+* This source code is licensed under the MIT license found in the
+* LICENSE file in the root directory of this source tree.
+*/
+
+
+'use strict';
+
+var d3 = require('d3');
+var tinycolor = require('tinycolor2');
+var isNumeric = require('fast-isnumeric');
+
+var Color = require('../color');
+
+/**
+ * General colorscale function generator.
+ *
+ * @param {object} specs output of Colorscale.extractScale or precomputed domain, range.
+ *  - domain {array}
+ *  - range {array}
+ *
+ * @param {object} opts
+ *  - noNumericCheck {boolean} if true, scale func bypasses numeric checks
+ *  - returnArray {boolean} if true, scale func return 4-item array instead of color strings
+ *
+ * @return {function}
+ */
+module.exports = function makeColorScaleFunc(specs, opts) {
+    opts = opts || {};
+
+    var domain = specs.domain,
+        range = specs.range,
+        N = range.length,
+        _range = new Array(N);
+
+    for(var i = 0; i < N; i++) {
+        var rgba = tinycolor(range[i]).toRgb();
+        _range[i] = [rgba.r, rgba.g, rgba.b, rgba.a];
+    }
+
+    var _sclFunc = d3.scale.linear()
+        .domain(domain)
+        .range(_range)
+        .clamp(true);
+
+    var noNumericCheck = opts.noNumericCheck,
+        returnArray = opts.returnArray,
+        sclFunc;
+
+    if(noNumericCheck && returnArray) {
+        sclFunc = _sclFunc;
+    }
+    else if(noNumericCheck) {
+        sclFunc = function(v) {
+            return colorArray2rbga(_sclFunc(v));
+        };
+    }
+    else if(returnArray) {
+        sclFunc = function(v) {
+            if(isNumeric(v)) return _sclFunc(v);
+            else if(tinycolor(v).isValid()) return v;
+            else return Color.defaultLine;
+        };
+    }
+    else {
+        sclFunc = function(v) {
+            if(isNumeric(v)) return colorArray2rbga(_sclFunc(v));
+            else if(tinycolor(v).isValid()) return v;
+            else return Color.defaultLine;
+        };
+    }
+
+    // colorbar draw looks into the d3 scale closure for domain and range
+
+    sclFunc.domain = _sclFunc.domain;
+
+    sclFunc.range = function() { return range; };
+
+    return sclFunc;
+};
+
+function colorArray2rbga(colorArray) {
+    var colorObj = {
+        r: colorArray[0],
+        g: colorArray[1],
+        b: colorArray[2],
+        a: colorArray[3]
+    };
+
+    return tinycolor(colorObj).toRgbString();
+}
diff --git a/src/components/colorscale/make_scale_function.js b/src/components/colorscale/make_scale_function.js
deleted file mode 100644
index 041217e4e37..00000000000
--- a/src/components/colorscale/make_scale_function.js
+++ /dev/null
@@ -1,47 +0,0 @@
-/**
-* Copyright 2012-2016, Plotly, Inc.
-* All rights reserved.
-*
-* This source code is licensed under the MIT license found in the
-* LICENSE file in the root directory of this source tree.
-*/
-
-
-'use strict';
-
-var d3 = require('d3');
-var tinycolor = require('tinycolor2');
-var isNumeric = require('fast-isnumeric');
-
-var Lib = require('../../lib');
-var Color = require('../color');
-
-
-module.exports = function makeScaleFunction(scl, cmin, cmax) {
-    var N = scl.length,
-        domain = new Array(N),
-        range = new Array(N),
-        si;
-
-    for(var i = 0; i < N; i++) {
-        si = scl[i];
-        domain[i] = cmin + si[0] * (cmax - cmin);
-        range[i] = tinycolor(si[1]).toRgb();
-    }
-
-    var sclFunc = d3.scale.linear()
-        .domain(domain)
-        .interpolate(d3.interpolateObject)
-        .range(range);
-
-    return function(v) {
-        if(isNumeric(v)) {
-            var sclVal = Lib.constrain(v, cmin, cmax),
-                colorObj = sclFunc(sclVal);
-
-            return tinycolor(colorObj).toRgbString();
-        }
-        else if(tinycolor(v).isValid()) return v;
-        else return Color.defaultLine;
-    };
-};
diff --git a/src/components/drawing/index.js b/src/components/drawing/index.js
index b4f1c5581e5..34e2572bc8d 100644
--- a/src/components/drawing/index.js
+++ b/src/components/drawing/index.js
@@ -331,7 +331,10 @@ drawing.tryColorscale = function(cont, contIn, prefix) {
             Lib.nestedProperty(contIn, prefix + 'cmin').set(min);
             Lib.nestedProperty(contIn, prefix + 'cmax').set(max);
         }
-        return Colorscale.makeScaleFunction(scl, min, max);
+
+        return Colorscale.makeColorScaleFunc(
+            Colorscale.extractScale(scl, min, max)
+        );
     }
     else return Lib.identity;
 };
diff --git a/src/lib/gl_format_color.js b/src/lib/gl_format_color.js
index 79937b6a7dc..73af3ca64e2 100644
--- a/src/lib/gl_format_color.js
+++ b/src/lib/gl_format_color.js
@@ -12,7 +12,7 @@
 var tinycolor = require('tinycolor2');
 var isNumeric = require('fast-isnumeric');
 
-var makeScaleFunction = require('../components/colorscale/make_scale_function');
+var Colorscale = require('../components/colorscale');
 var colorDflt = require('../components/color/attributes').defaultLine;
 
 var str2RgbaArray = require('./str2rgbarray');
@@ -42,8 +42,12 @@ function formatColor(containerIn, opacityIn, len) {
     var sclFunc, getColor, getOpacity, colori, opacityi;
 
     if(containerIn.colorscale !== undefined) {
-        sclFunc = makeScaleFunction(
-            containerIn.colorscale, containerIn.cmin, containerIn.cmax
+        sclFunc = Colorscale.makeColorScaleFunc(
+            Colorscale.extractScale(
+                containerIn.colorscale,
+                containerIn.cmin,
+                containerIn.cmax
+            )
         );
     }
     else sclFunc = validateColor;
diff --git a/src/traces/choropleth/plot.js b/src/traces/choropleth/plot.js
index 2b787c6b1a7..07e92f94d5a 100644
--- a/src/traces/choropleth/plot.js
+++ b/src/traces/choropleth/plot.js
@@ -15,9 +15,8 @@ var Axes = require('../../plots/cartesian/axes');
 var Fx = require('../../plots/cartesian/graph_interact');
 var Color = require('../../components/color');
 var Drawing = require('../../components/drawing');
+var Colorscale = require('../../components/colorscale');
 
-var getColorscale = require('../../components/colorscale/get_scale');
-var makeScaleFunction = require('../../components/colorscale/make_scale_function');
 var getTopojsonFeatures = require('../../lib/topojson_utils').getTopojsonFeatures;
 var locationToFeature = require('../../lib/geo_location_utils').locationToFeature;
 var arrayToCalcItem = require('../../lib/array_to_calc_item');
@@ -151,11 +150,15 @@ plotChoropleth.style = function(geo) {
             var trace = calcTrace[0].trace,
                 s = d3.select(this),
                 marker = trace.marker || {},
-                markerLine = marker.line || {},
-                zmin = trace.zmin,
-                zmax = trace.zmax,
-                scl = getColorscale(trace.colorscale),
-                sclFunc = makeScaleFunction(scl, zmin, zmax);
+                markerLine = marker.line || {};
+
+            var sclFunc = Colorscale.makeColorScaleFunc(
+                Colorscale.extractScale(
+                    trace.colorscale,
+                    trace.zmin,
+                    trace.zmax
+                )
+            );
 
             s.selectAll('path.choroplethlocation')
                 .each(function(pt) {
diff --git a/src/traces/contour/make_color_map.js b/src/traces/contour/make_color_map.js
index 0b37b4ee20d..9227d0fbf73 100644
--- a/src/traces/contour/make_color_map.js
+++ b/src/traces/contour/make_color_map.js
@@ -10,9 +10,7 @@
 'use strict';
 
 var d3 = require('d3');
-
-var getColorscale = require('../../components/colorscale/get_scale');
-
+var Colorscale = require('../../components/colorscale');
 
 module.exports = function makeColorMap(trace) {
     var contours = trace.contours,
@@ -22,7 +20,7 @@ module.exports = function makeColorMap(trace) {
         nc = Math.floor((end + cs / 10 - start) / cs) + 1,
         extra = contours.coloring === 'lines' ? 0 : 1;
 
-    var scl = getColorscale(trace.colorscale),
+    var scl = trace.colorscale,
         len = scl.length;
 
     var domain = new Array(len),
@@ -69,10 +67,10 @@ module.exports = function makeColorMap(trace) {
         }
     }
 
-    var colorMap = d3.scale.linear()
-        .interpolate(d3.interpolateRgb)
-        .domain(domain)
-        .range(range);
-
-    return colorMap;
+    return Colorscale.makeColorScaleFunc({
+        domain: domain,
+        range: range,
+    }, {
+        noNumericCheck: true
+    });
 };
diff --git a/src/traces/heatmap/colorbar.js b/src/traces/heatmap/colorbar.js
index 34b318f6afb..fdaf5a54215 100644
--- a/src/traces/heatmap/colorbar.js
+++ b/src/traces/heatmap/colorbar.js
@@ -9,19 +9,17 @@
 
 'use strict';
 
-var d3 = require('d3');
 var isNumeric = require('fast-isnumeric');
 
 var Lib = require('../../lib');
 var Plots = require('../../plots/plots');
-var getColorscale = require('../../components/colorscale/get_scale');
+var Colorscale = require('../../components/colorscale');
 var drawColorbar = require('../../components/colorbar/draw');
 
 
 module.exports = function colorbar(gd, cd) {
     var trace = cd[0].trace,
         cbId = 'cb' + trace.uid,
-        scl = getColorscale(trace.colorscale),
         zmin = trace.zmin,
         zmax = trace.zmax;
 
@@ -36,9 +34,16 @@ module.exports = function colorbar(gd, cd) {
     }
 
     var cb = cd[0].t.cb = drawColorbar(gd, cbId);
-    cb.fillcolor(d3.scale.linear()
-            .domain(scl.map(function(v) { return zmin + v[0] * (zmax - zmin); }))
-            .range(scl.map(function(v) { return v[1]; })))
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            trace.colorscale,
+            zmin,
+            zmax
+        ),
+        { noNumericCheck: true }
+    );
+
+    cb.fillcolor(sclFunc)
         .filllevels({start: zmin, end: zmax, size: (zmax - zmin) / 254})
         .options(trace.colorbar)();
 };
diff --git a/src/traces/heatmap/plot.js b/src/traces/heatmap/plot.js
index e1d6694ddd1..21d530f8c80 100644
--- a/src/traces/heatmap/plot.js
+++ b/src/traces/heatmap/plot.js
@@ -9,12 +9,11 @@
 
 'use strict';
 
-var d3 = require('d3');
 var tinycolor = require('tinycolor2');
 
 var Registry = require('../../registry');
 var Lib = require('../../lib');
-var getColorscale = require('../../components/colorscale/get_scale');
+var Colorscale = require('../../components/colorscale');
 var xmlnsNamespaces = require('../../constants/xmlns_namespaces');
 
 var maxRowLength = require('./max_row_length');
@@ -45,9 +44,6 @@ function plotOne(gd, plotinfo, cd) {
     }
 
     var z = cd[0].z,
-        min = trace.zmin,
-        max = trace.zmax,
-        scl = getColorscale(trace.colorscale),
         x = cd[0].x,
         y = cd[0].y,
         isContour = Registry.traceIs(trace, 'contour'),
@@ -170,15 +166,14 @@ function plotOne(gd, plotinfo, cd) {
     canvas.height = canvasH;
     var context = canvas.getContext('2d');
 
-    // interpolate for color scale
-    // use an array instead of color strings, so we preserve alpha
-    var s = d3.scale.linear()
-        .domain(scl.map(function(si) { return si[0]; }))
-        .range(scl.map(function(si) {
-            var c = tinycolor(si[1]).toRgb();
-            return [c.r, c.g, c.b, c.a];
-        }))
-        .clamp(true);
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            trace.colorscale,
+            trace.zmin,
+            trace.zmax
+        ),
+        { noNumericCheck: true, returnArray: true }
+    );
 
     // map brick boundaries to image pixels
     var xpx,
@@ -289,7 +284,7 @@ function plotOne(gd, plotinfo, cd) {
 
     function setColor(v, pixsize) {
         if(v !== undefined) {
-            var c = s((v - min) / (max - min));
+            var c = sclFunc(v);
             c[0] = Math.round(c[0]);
             c[1] = Math.round(c[1]);
             c[2] = Math.round(c[2]);
diff --git a/src/traces/scatter/colorbar.js b/src/traces/scatter/colorbar.js
index 2a3e7a08b13..d98d23e962f 100644
--- a/src/traces/scatter/colorbar.js
+++ b/src/traces/scatter/colorbar.js
@@ -9,12 +9,11 @@
 
 'use strict';
 
-var d3 = require('d3');
 var isNumeric = require('fast-isnumeric');
 
 var Lib = require('../../lib');
 var Plots = require('../../plots/plots');
-var getColorscale = require('../../components/colorscale/get_scale');
+var Colorscale = require('../../components/colorscale');
 var drawColorbar = require('../../components/colorbar/draw');
 
 
@@ -25,16 +24,15 @@ module.exports = function colorbar(gd, cd) {
 
     gd._fullLayout._infolayer.selectAll('.' + cbId).remove();
 
-    // TODO unify Scatter.colorbar and Heatmap.colorbar
-    // TODO make Plotly[module].colorbar support multiple colorbar per trace
+    // TODO unify scatter and heatmap colorbar
+    // TODO make Colorbar.draw support multiple colorbar per trace
 
     if((marker === undefined) || !marker.showscale) {
         Plots.autoMargin(gd, cbId);
         return;
     }
 
-    var scl = getColorscale(marker.colorscale),
-        vals = marker.color,
+    var vals = marker.color,
         cmin = marker.cmin,
         cmax = marker.cmax;
 
@@ -42,10 +40,16 @@ module.exports = function colorbar(gd, cd) {
     if(!isNumeric(cmax)) cmax = Lib.aggNums(Math.max, null, vals);
 
     var cb = cd[0].t.cb = drawColorbar(gd, cbId);
-
-    cb.fillcolor(d3.scale.linear()
-            .domain(scl.map(function(v) { return cmin + v[0] * (cmax - cmin); }))
-            .range(scl.map(function(v) { return v[1]; })))
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            marker.colorscale,
+            cmin,
+            cmax
+        ),
+        { noNumericCheck: true }
+    );
+
+    cb.fillcolor(sclFunc)
         .filllevels({start: cmin, end: cmax, size: (cmax - cmin) / 254})
         .options(marker.colorbar)();
 };
diff --git a/src/traces/scattermapbox/calc.js b/src/traces/scattermapbox/calc.js
index a3c6f50df57..ecf8d9ee8cb 100644
--- a/src/traces/scattermapbox/calc.js
+++ b/src/traces/scattermapbox/calc.js
@@ -12,8 +12,8 @@
 var isNumeric = require('fast-isnumeric');
 
 var Lib = require('../../lib');
-var hasColorscale = require('../../components/colorscale/has_colorscale');
-var makeColorScaleFn = require('../../components/colorscale/make_scale_function');
+var Colorscale = require('../../components/colorscale');
+
 var subtypes = require('../scatter/subtypes');
 var calcMarkerColorscale = require('../scatter/colorscale_calc');
 var makeBubbleSizeFn = require('../scatter/make_bubble_size_func');
@@ -31,8 +31,14 @@ module.exports = function calc(gd, trace) {
 
     calcMarkerColorscale(trace);
 
-    var colorFn = hasColorscale(trace, 'marker') ?
-            makeColorScaleFn(marker.colorscale, marker.cmin, marker.cmax) :
+    var colorFn = Colorscale.hasColorscale(trace, 'marker') ?
+            Colorscale.makeColorScaleFunc(
+                Colorscale.extractScale(
+                    marker.colorscale,
+                    marker.cmin,
+                    marker.cmax
+                )
+            ) :
             Lib.identity;
 
     var sizeFn = subtypes.isBubble(trace) ?
diff --git a/src/traces/surface/colorbar.js b/src/traces/surface/colorbar.js
index 02cb8ef2f04..044f26db4b8 100644
--- a/src/traces/surface/colorbar.js
+++ b/src/traces/surface/colorbar.js
@@ -9,25 +9,23 @@
 
 'use strict';
 
-var d3 = require('d3');
 var isNumeric = require('fast-isnumeric');
 
 var Lib = require('../../lib');
 var Plots = require('../../plots/plots');
-var getColorscale = require('../../components/colorscale/get_scale');
+var Colorscale = require('../../components/colorscale');
 var drawColorbar = require('../../components/colorbar/draw');
 
 
 module.exports = function colorbar(gd, cd) {
     var trace = cd[0].trace,
         cbId = 'cb' + trace.uid,
-        scl = getColorscale(trace.colorscale),
-        zmin = trace.cmin,
-        zmax = trace.cmax,
+        cmin = trace.cmin,
+        cmax = trace.cmax,
         vals = trace.surfacecolor || trace.z;
 
-    if(!isNumeric(zmin)) zmin = Lib.aggNums(Math.min, null, vals);
-    if(!isNumeric(zmax)) zmax = Lib.aggNums(Math.max, null, vals);
+    if(!isNumeric(cmin)) cmin = Lib.aggNums(Math.min, null, vals);
+    if(!isNumeric(cmax)) cmax = Lib.aggNums(Math.max, null, vals);
 
     gd._fullLayout._infolayer.selectAll('.' + cbId).remove();
 
@@ -37,9 +35,16 @@ module.exports = function colorbar(gd, cd) {
     }
 
     var cb = cd[0].t.cb = drawColorbar(gd, cbId);
-    cb.fillcolor(d3.scale.linear()
-            .domain(scl.map(function(v) { return zmin + v[0] * (zmax - zmin); }))
-            .range(scl.map(function(v) { return v[1]; })))
-        .filllevels({start: zmin, end: zmax, size: (zmax - zmin) / 254})
+    var sclFunc = Colorscale.makeColorScaleFunc(
+        Colorscale.extractScale(
+            trace.colorscale,
+            cmin,
+            cmax
+        ),
+        { noNumericCheck: true }
+    );
+
+    cb.fillcolor(sclFunc)
+        .filllevels({start: cmin, end: cmax, size: (cmax - cmin) / 254})
         .options(trace.colorbar)();
 };
diff --git a/test/image/baselines/colorscale_opacity.png b/test/image/baselines/colorscale_opacity.png
index 7816120ecce..d7c4208301c 100644
Binary files a/test/image/baselines/colorscale_opacity.png and b/test/image/baselines/colorscale_opacity.png differ
diff --git a/test/image/baselines/geo_bubbles-colorscales.png b/test/image/baselines/geo_bubbles-colorscales.png
index 57c73a839bc..1f0fba6a561 100644
Binary files a/test/image/baselines/geo_bubbles-colorscales.png and b/test/image/baselines/geo_bubbles-colorscales.png differ
diff --git a/test/image/baselines/gl3d_scatter-colorscale-marker.png b/test/image/baselines/gl3d_scatter-colorscale-marker.png
index 7a4c4156a99..f3b29555313 100644
Binary files a/test/image/baselines/gl3d_scatter-colorscale-marker.png and b/test/image/baselines/gl3d_scatter-colorscale-marker.png differ
diff --git a/test/image/mocks/colorscale_opacity.json b/test/image/mocks/colorscale_opacity.json
index 9da112f70dd..29c4b93b9db 100644
--- a/test/image/mocks/colorscale_opacity.json
+++ b/test/image/mocks/colorscale_opacity.json
@@ -1,6 +1,523 @@
 {
     "data": [
         {
+         "type": "contour",
+         "z":[
+            [
+               1,
+               1.126592,
+               1.251148,
+               1.371662,
+               1.486197,
+               1.592908,
+               1.690079,
+               1.776146,
+               1.849725,
+               1.909632,
+               1.954902,
+               1.984808,
+               1.998867,
+               1.996855,
+               1.978802,
+               1.945001,
+               1.895994,
+               1.83257,
+               1.75575,
+               1.666769,
+               1.56706,
+               1.458227,
+               1.34202,
+               1.220311,
+               1.095056,
+               0.968272,
+               0.841999,
+               0.718267,
+               0.599069,
+               0.486323,
+               0.381841,
+               0.287306,
+               0.204238,
+               0.133975,
+               0.077646,
+               0.036158,
+               0.010179,
+               0.000126,
+               0.006162,
+               0.028188,
+               0.065852,
+               0.118547,
+               0.185424,
+               0.265408,
+               0.357212,
+               0.459359,
+               0.570205,
+               0.687967,
+               0.810749,
+               0.936576,
+               1.063424,
+               1.189251,
+               1.312033,
+               1.429795,
+               1.540641,
+               1.642788,
+               1.734592,
+               1.814576,
+               1.881453,
+               1.934148,
+               1.971812,
+               1.993838,
+               1.999874,
+               1.989821,
+               1.963842,
+               1.922354,
+               1.866025,
+               1.795762,
+               1.712694,
+               1.618159,
+               1.513677,
+               1.400931,
+               1.281733,
+               1.158001,
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+               0.309921,
+               0.407092,
+               0.513803,
+               0.628338,
+               0.748852,
+               0.873408,
+               1
+            ],
+            [
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+            ],
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+               0.014484,
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+               -0.202744,
+               -0.297279,
+               -0.380347,
+               -0.45061,
+               -0.506939,
+               -0.548427,
+               -0.574406,
+               -0.584459,
+               -0.578423,
+               -0.556397,
+               -0.518733,
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+               0.351991,
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+               0.84521,
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+               1.058203,
+               1.150007,
+               1.229991,
+               1.296868,
+               1.349563,
+               1.387227,
+               1.409253,
+               1.415289,
+               1.405236,
+               1.379257,
+               1.337769,
+               1.28144,
+               1.211177,
+               1.128109,
+               1.033574,
+               0.929092,
+               0.816346,
+               0.697148,
+               0.573416,
+               0.447143,
+               0.320359,
+               0.195104,
+               0.073395,
+               -0.042812,
+               -0.151645,
+               -0.251354,
+               -0.340335,
+               -0.417155,
+               -0.480579,
+               -0.529586,
+               -0.563387,
+               -0.58144,
+               -0.583452,
+               -0.569393,
+               -0.539487,
+               -0.494217,
+               -0.43431,
+               -0.360731,
+               -0.274664,
+               -0.177493,
+               -0.070782,
+               0.043753,
+               0.164267,
+               0.288823,
+               0.415415
+            ]
+          ],
+          "colorscale": [[0, "rgba(255,0,0,0.2)"], [1, "rgba(0,255,0,0.8)"]]
+        },
+        {
+            "dx": 15,
             "y": [
                 5,
                 5,
@@ -33,7 +550,7 @@
         }
     ],
     "layout": {
-        "title": "Scatter Plot with a Color Dimension",
+        "title": "RGBA colorscales",
         "xaxis": {
             "range": [
                 -0.271356783919598,
diff --git a/test/jasmine/tests/colorscale_test.js b/test/jasmine/tests/colorscale_test.js
index 3610c17cdec..462d53c2a08 100644
--- a/test/jasmine/tests/colorscale_test.js
+++ b/test/jasmine/tests/colorscale_test.js
@@ -378,22 +378,24 @@ describe('Test colorscale:', function() {
 
     });
 
-    describe('makeScaleFunction', function() {
+    describe('extractScale + makeColorScaleFunc', function() {
         var scale = [
-                [0, 'rgb(5,10,172)'],
-                [0.35, 'rgb(106,137,247)'],
-                [0.5, 'rgb(190,190,190)'],
-                [0.6, 'rgb(220,170,132)'],
-                [0.7, 'rgb(230,145,90)'],
-                [1, 'rgb(178,10,28)']
-            ],
-            scaleFunction = Colorscale.makeScaleFunction(scale, 2, 3);
+            [0, 'rgb(5,10,172)'],
+            [0.35, 'rgb(106,137,247)'],
+            [0.5, 'rgb(190,190,190)'],
+            [0.6, 'rgb(220,170,132)'],
+            [0.7, 'rgb(230,145,90)'],
+            [1, 'rgb(178,10,28)']
+        ];
+
+        var specs = Colorscale.extractScale(scale, 2, 3);
+        var sclFunc = Colorscale.makeColorScaleFunc(specs);
 
         it('should constrain color array values between cmin and cmax', function() {
-            var color1 = scaleFunction(1),
-                color2 = scaleFunction(2),
-                color3 = scaleFunction(3),
-                color4 = scaleFunction(4);
+            var color1 = sclFunc(1),
+                color2 = sclFunc(2),
+                color3 = sclFunc(3),
+                color4 = sclFunc(4);
 
             expect(color1).toEqual(color2);
             expect(color1).toEqual('rgb(5, 10, 172)');