diff --git a/README.mkd b/README.mkd
index b539fd8..eb350d3 100644
--- a/README.mkd
+++ b/README.mkd
@@ -19,3 +19,9 @@ To run the whole node server:
 * run `node app.js` or `nodejs app.js` from the root directory.
 * navigate to http://localhost:8001/sandbox/
 
+You'll need coffeescript (`sudo apt-get install coffeescript`) to compile the javascript source. After editing the various .coffee files in the public directory, run make to compile them:
+
+* `cd public`
+* `make`
+
+
diff --git a/public/infragram.coffee b/public/infragram.coffee
index 84eb40a..fe16f56 100644
--- a/public/infragram.coffee
+++ b/public/infragram.coffee
@@ -204,26 +204,26 @@ update = (img) ->
         render(result)
 
 save_expressions = (r,g,b) ->
-        r = r.toUpperCase().replace(/X/g,$('#slider').val()/100)
-        g = g.toUpperCase().replace(/X/g,$('#slider').val()/100)
-        b = b.toUpperCase().replace(/X/g,$('#slider').val()/100)
+        r = r.replace(/X/g,$('#slider').val()/100)
+        g = g.replace(/X/g,$('#slider').val()/100)
+        b = b.replace(/X/g,$('#slider').val()/100)
         r = "R" if r == ""
         g = "G" if g == ""
         b = "B" if b == ""
-        eval("r_exp = function(R,G,B){return "+r+";}")
-        eval("g_exp = function(R,G,B){return "+g+";}")
-        eval("b_exp = function(R,G,B){return "+b+";}")
+        eval("r_exp = function(R,G,B){var r=R,g=G,b=B;return "+r+";}")
+        eval("g_exp = function(R,G,B){var r=R,g=G,b=B;return "+g+";}")
+        eval("b_exp = function(R,G,B){var r=R,g=G,b=B;return "+b+";}")
 
 save_expressions_hsv = (h,s,v) ->
-        h = h.toUpperCase().replace(/X/g,$('#slider').val()/100)
-        s = s.toUpperCase().replace(/X/g,$('#slider').val()/100)
-        v = v.toUpperCase().replace(/X/g,$('#slider').val()/100)
+        h = h.replace(/X/g,$('#slider').val()/100)
+        s = s.replace(/X/g,$('#slider').val()/100)
+        v = v.replace(/X/g,$('#slider').val()/100)
         h = "H" if h == ""
         s = "S" if s == ""
         v = "V" if v == ""
-        eval("r_exp = function(R,G,B){var hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb("+h+","+s+","+v+")[0];}")
-        eval("g_exp = function(R,G,B){var hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb("+h+","+s+","+v+")[1];}")
-        eval("b_exp = function(R,G,B){var hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb("+h+","+s+","+v+")[2];}")
+        eval("r_exp = function(R,G,B){var h=H,s=S,v=V,hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb("+h+","+s+","+v+")[0];}")
+        eval("g_exp = function(R,G,B){var h=H,s=S,v=V,hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb("+h+","+s+","+v+")[1];}")
+        eval("b_exp = function(R,G,B){var h=H,s=S,v=V,hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb("+h+","+s+","+v+")[2];}")
 
 # modified from:
 # http://axonflux.com/handy-rgb-to-hsl-and-rgb-to-hsv-color-model-c
diff --git a/public/infragram.js b/public/infragram.js
index 4837c9a..bc39229 100644
--- a/public/infragram.js
+++ b/public/infragram.js
@@ -1,5 +1,6 @@
-// Generated by CoffeeScript 1.7.1
-var FileUpload, JsImage, b_exp, camera, colorized, colormap, colormap1, colormap2, createBuffer, createContext, createTexture, decodeParameters, downloadImage, drawScene, fetch_image, g_exp, generateShader, getCurrentImage, getURLParameter, get_channels, glGetCurrentImage, glHandleDefaultColormap, glHandleOnClickColor, glHandleOnClickGrey, glHandleOnClickNdvi, glHandleOnClickRaw, glHandleOnSlide, glHandleOnSubmitInfra, glHandleOnSubmitInfraHsv, glHandleOnSubmitInfraMono, glHandleStretchedColormap, glInitInfragram, glRestoreContext, glRunInfragrammar, glSaveExpression, glSetMode, glShaderLoaded, glUpdateImage, greyscale_colormap, histogram, hsv2rgb, image, imgContext, infragrammar, infragrammar_mono, jsColorify, jsGetCurrentImage, jsHandleOnClickGrey, jsHandleOnClickNdvi, jsHandleOnClickRaw, jsHandleOnSlide, jsHandleOnSubmitInfra, jsHandleOnSubmitInfraHsv, jsHandleOnSubmitInfraMono, jsRunInfragrammar, jsUpdateImage, log, log_hsv, log_mono, log_rgb, m_exp, mapContext, mode, ndvi, parametersObject, params, r_exp, render, rgb2hsv, run_colorize, run_infragrammar, save_expressions, save_expressions_hsv, save_infragrammar_expressions, save_infragrammar_inputs, save_log, segmented_colormap, setParametersFromURL, set_mode, update, updateImage, update_colorbar, vertices, video_live, waitForShadersToLoad, webGlSupported;
+// Generated by CoffeeScript 1.4.0
+var FileUpload, JsImage, b_exp, camera, colorized, colormap, colormap1, colormap2, createBuffer, createContext, createTexture, decodeParameters, downloadImage, drawScene, fetch_image, g_exp, generateShader, getCurrentImage, getURLParameter, get_channels, glGetCurrentImage, glHandleDefaultColormap, glHandleOnClickColor, glHandleOnClickGrey, glHandleOnClickNdvi, glHandleOnClickRaw, glHandleOnSlide, glHandleOnSubmitInfra, glHandleOnSubmitInfraHsv, glHandleOnSubmitInfraMono, glHandleStretchedColormap, glInitInfragram, glRestoreContext, glRunInfragrammar, glSaveExpression, glSetMode, glShaderLoaded, glUpdateImage, greyscale_colormap, histogram, hsv2rgb, image, imgContext, infragrammar, infragrammar_mono, jsColorify, jsGetCurrentImage, jsHandleOnClickGrey, jsHandleOnClickNdvi, jsHandleOnClickRaw, jsHandleOnSlide, jsHandleOnSubmitInfra, jsHandleOnSubmitInfraHsv, jsHandleOnSubmitInfraMono, jsRunInfragrammar, jsUpdateImage, log, log_hsv, log_mono, log_rgb, m_exp, mapContext, mode, ndvi, parametersObject, params, r_exp, render, rgb2hsv, run_colorize, run_infragrammar, save_expressions, save_expressions_hsv, save_infragrammar_expressions, save_infragrammar_inputs, save_log, segmented_colormap, setParametersFromURL, set_mode, update, updateImage, update_colorbar, vertices, video_live, waitForShadersToLoad, webGlSupported,
+  _this = this;
 
 image = null;
 
@@ -14,6 +15,7 @@ b_exp = "";
 m_exp = "";
 
 JsImage = (function() {
+
   function JsImage(data, width, height, channels) {
     this.data = data;
     this.width = width;
@@ -215,28 +217,26 @@ colormap2 = segmented_colormap([[0, [0, 0, 255], [0, 0, 255]], [0.1, [0, 0, 255]
 
 colormap = colormap1;
 
-update_colorbar = (function(_this) {
-  return function(min, max) {
-    var b, ctx, d, e, g, i, j, k, r, _i, _j, _ref, _ref1, _ref2;
-    $('#colorbar-container')[0].style.display = 'inline-block';
-    e = $('#colorbar')[0];
-    ctx = e.getContext("2d");
-    d = ctx.getImageData(0, 0, e.width, e.height);
-    for (i = _i = 0, _ref = e.width; 0 <= _ref ? _i < _ref : _i > _ref; i = 0 <= _ref ? ++_i : --_i) {
-      for (j = _j = 0, _ref1 = e.height; 0 <= _ref1 ? _j < _ref1 : _j > _ref1; j = 0 <= _ref1 ? ++_j : --_j) {
-        _ref2 = colormap(i / e.width), r = _ref2[0], g = _ref2[1], b = _ref2[2];
-        k = 4 * (i + j * e.width);
-        d.data[k + 0] = r;
-        d.data[k + 1] = g;
-        d.data[k + 2] = b;
-        d.data[k + 3] = 255;
-      }
+update_colorbar = function(min, max) {
+  var b, ctx, d, e, g, i, j, k, r, _i, _j, _ref, _ref1, _ref2;
+  $('#colorbar-container')[0].style.display = 'inline-block';
+  e = $('#colorbar')[0];
+  ctx = e.getContext("2d");
+  d = ctx.getImageData(0, 0, e.width, e.height);
+  for (i = _i = 0, _ref = e.width; 0 <= _ref ? _i < _ref : _i > _ref; i = 0 <= _ref ? ++_i : --_i) {
+    for (j = _j = 0, _ref1 = e.height; 0 <= _ref1 ? _j < _ref1 : _j > _ref1; j = 0 <= _ref1 ? ++_j : --_j) {
+      _ref2 = colormap(i / e.width), r = _ref2[0], g = _ref2[1], b = _ref2[2];
+      k = 4 * (i + j * e.width);
+      d.data[k + 0] = r;
+      d.data[k + 1] = g;
+      d.data[k + 2] = b;
+      d.data[k + 3] = 255;
     }
-    ctx.putImageData(d, 0, 0);
-    $("#colorbar-min")[0].textContent = min.toFixed(2);
-    return $("#colorbar-max")[0].textContent = max.toFixed(2);
-  };
-})(this);
+  }
+  ctx.putImageData(d, 0, 0);
+  $("#colorbar-min")[0].textContent = min.toFixed(2);
+  return $("#colorbar-max")[0].textContent = max.toFixed(2);
+};
 
 update = function(img) {
   var b, g, max, min, ndvi_img, normalize, r, result, _ref, _ref1;
@@ -267,9 +267,9 @@ update = function(img) {
 };
 
 save_expressions = function(r, g, b) {
-  r = r.toUpperCase().replace(/X/g, $('#slider').val() / 100);
-  g = g.toUpperCase().replace(/X/g, $('#slider').val() / 100);
-  b = b.toUpperCase().replace(/X/g, $('#slider').val() / 100);
+  r = r.replace(/X/g, $('#slider').val() / 100);
+  g = g.replace(/X/g, $('#slider').val() / 100);
+  b = b.replace(/X/g, $('#slider').val() / 100);
   if (r === "") {
     r = "R";
   }
@@ -279,15 +279,15 @@ save_expressions = function(r, g, b) {
   if (b === "") {
     b = "B";
   }
-  eval("r_exp = function(R,G,B){return " + r + ";}");
-  eval("g_exp = function(R,G,B){return " + g + ";}");
-  return eval("b_exp = function(R,G,B){return " + b + ";}");
+  eval("r_exp = function(R,G,B){var r=R,g=G,b=B;return " + r + ";}");
+  eval("g_exp = function(R,G,B){var r=R,g=G,b=B;return " + g + ";}");
+  return eval("b_exp = function(R,G,B){var r=R,g=G,b=B;return " + b + ";}");
 };
 
 save_expressions_hsv = function(h, s, v) {
-  h = h.toUpperCase().replace(/X/g, $('#slider').val() / 100);
-  s = s.toUpperCase().replace(/X/g, $('#slider').val() / 100);
-  v = v.toUpperCase().replace(/X/g, $('#slider').val() / 100);
+  h = h.replace(/X/g, $('#slider').val() / 100);
+  s = s.replace(/X/g, $('#slider').val() / 100);
+  v = v.replace(/X/g, $('#slider').val() / 100);
   if (h === "") {
     h = "H";
   }
@@ -297,9 +297,9 @@ save_expressions_hsv = function(h, s, v) {
   if (v === "") {
     v = "V";
   }
-  eval("r_exp = function(R,G,B){var hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb(" + h + "," + s + "," + v + ")[0];}");
-  eval("g_exp = function(R,G,B){var hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb(" + h + "," + s + "," + v + ")[1];}");
-  return eval("b_exp = function(R,G,B){var hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb(" + h + "," + s + "," + v + ")[2];}");
+  eval("r_exp = function(R,G,B){var h=H,s=S,v=V,hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb(" + h + "," + s + "," + v + ")[0];}");
+  eval("g_exp = function(R,G,B){var h=H,s=S,v=V,hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb(" + h + "," + s + "," + v + ")[1];}");
+  return eval("b_exp = function(R,G,B){var h=H,s=S,v=V,hsv = rgb2hsv(R, G, B), H = hsv[0], S = hsv[1], V = hsv[2]; return hsv2rgb(" + h + "," + s + "," + v + ")[2];}");
 };
 
 hsv2rgb = function(h, s, v) {
diff --git a/views/layout.jade b/views/layout.jade
index 0cde322..6be0a6c 100644
--- a/views/layout.jade
+++ b/views/layout.jade
@@ -17,7 +17,7 @@ html
     script(src="/bootstrap/js/bootstrap-slider.js")
     script(src="/socket.io/socket.io.js")
     script(src="/webgl-utils.js")
-    script(src="/infragram.js?hash=4837c9a132bd450a6a5f2d60163dbd335d1f3534")
+    script(src="/infragram.js?hash=bc3922928c235167f815afa0f517c480779bc51c")
 
     script#shader-vs(type="x-shader/x-vertex")
     script#shader-fs-template(type="x-shader/x-fragment")