first draft of configurable variables

README.md

@@ -6,3 +6,18 @@ A stepper motor controller for use in photography.
 
 This is the ideal case for the build:
 https://www.thingiverse.com/thing:142282/files
+
+## Configurable values
+
+### General configuration
+
+- Settle time: pause between camera move and shutter trigger.
+- Focus time: how long to focus before triggering.
+- Shutter time: how long to press the trigger.
+- Return after scene: return to starting point after shooting.
+- LCD blackout: turn off LCD backlight while shutter is open.
+
+### Scene configuration
+
+- Steps: number of steps for this scene.
+- Distance per step: how far to move between the steps.