improved README

README.md

@@ -2,37 +2,100 @@
 
 A stepper motor controller for use in photography.
 
+This is a device that can be used to control a stepper motor and a camera, to
+make a defined number of photos with a defined movement in between. A stepper
+motor can be attached to a rotating platform or to a linear drive, so either
+the object or the camera can be moved between the pictures.
+
 ## Hardware
 
+The device consists of the following components:
+
+- Arduino Uno, the brains of the operation
+- LCD & keypad shield, as the user interface
+- an A4988 stepper motor driver
+- a 100uF capacitor
+- two PC817 opto-isolators
+- two 1k resistors
+
+The circuit is pretty simple:
+
+![Circuit](circuit/photostepper_bb.jpg)
+
+Atop of that, I used an M13 connector for the stepper motor and a 2.5mm stereo
+phone connector for the camera. To interface my camera, I had a ready made
+cable from a remot camera controller (Ayex AX-5). The whole thing is powered by
+a 12V power supply, connected directly to the Arduino.
+
 This is the ideal case for the build:
 https://www.thingiverse.com/thing:142282/files
 
-## Configurable values
+## Software
 
-### General configuration
+This project makes heavy use of the following libraries:
 
-- 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.
+- [ArduinoMenu 4](https://www.arduino.cc/reference/en/libraries/arduinomenu-library/) (v4.21.4) for the menu structure
+- [StepperDriver](https://www.arduino.cc/reference/en/libraries/stepperdriver/) (v1.3.1) for motor control
+- [AnalogKeypad by Makuna](https://www.arduino.cc/reference/en/libraries/analogkeypad/) (v1.1.1) for reading input keys
 
-### Scene configuration
+## Menu structure
 
-- Steps: number of steps for this scene.
-- Distance per step: how far to move between the steps.
+The main menu offers the following features:
+
+### Jog
+
+Up and down buttons move the motor manually, pressing the buttons for more than
+a second doubles the speed.
+
+### Configuration
+
+General settings for the device:
+
+#### Settle time (tSettle, default 1000ms)
+
+Pause between motor movement and camera triggers, to avoid shaking.
+
+#### Focus time (tFocus, default 1000ms)
+
+Half-press of the shutter button, time to let the camera focus.
+
+#### Shutter time (tShutter, default 1000ms)
+
+How long to press the trigger.
+
+#### Return (default: On)
+
+Reverse any movement to starting point after shooting the whole scene.
+
+#### DarkenLCD (default: Off)
+
+Turn off LCD backlight while shutter is open.
+
+### Scene
+
+#### Steps (nSteps, default 10)
+
+Number of steps for this scene.
+
+#### Distance per step (distance, default 0.5mm)
+
+How far to move between the steps.
+
+### Run
+
+Run the whole setup.
 
 ## Example results
 
 This is the first image that was made using this project:
 
-![](example_images/220213_macro_cent.jpg)
+![Extreme closeup of a coin](example_images/220213_macro_cent.jpg)
 
 Depth of field for my setup is a little more than 1mm, so this image is
 composed from 30 different shots, each 1mm apart. Here's an animation of the
 non-fused images:
 
-![](example_images/220213_macro_cent_-_animation.gif)
+![Animated focus stack](example_images/220213_macro_cent_-_animation.gif)
 
 The images were taken as JPG. For some reason the align-program did strange
 things with my full size images, so I reduced them in size first -- it's only a