update README

README.md

@@ -18,5 +18,17 @@ You'll end up with a bunch of `figure-###.png` PNGs in the `out` folder.
 
 ## Example Output
 
+These are shrunk by roughly half:
+
 ![figure-001.png](/../examples/figure-001.png?raw=true 'Figure 1')
 ![figure-002.png](/../examples/figure-002.png?raw=true 'Figure 2')
+
+## Photoshop script
+
+I've included `crop-coords.jsx` a Photoshop script that I made to help me efficiently mark the crop coordinates for each figure and copy them over to the makefile. The basic operation is that you pull out 4 guides to create the bounding box of your crop, then run the script. You'll then have your `x`, `y`, `width`, and `height` information copied to the clipboard.
+
+The easiest way to trigger the script is to record an action that runs the script. Then you just put your action pallet into "button mode" and click away.
+
+## Why Use Make?
+
+Please see [Mike Bostock's article, _Why Use Make_](http://bost.ocks.org/mike/make/). I mostly like the idea that – when I change my mind later about the settings I want to use (perhaps different level adjustments, or sharpening) – I can easily rerun the whole process, rather than heaping one lossy Photoshop batch job on top of another.