smart-pinhole-workshop/exercises/how_long_to_expose_film/problem.md

A nodeschool workshop to learn how smart (iot) things work.

Our camera is smart because it will tell us how long to leave the camera shutter open for.

Lets configure our `LightMeter UI` with different daylight conditions. We'll include the best film exposure for each condition.

Now, the `LightMeter UI` changes exposure time for different light conditions.

__Write a program that visualizes light conditions and best exposure time.__

Based on your previous solution, Configure `LightMeterWidget` using the `addLightingCondition()` method.

These allow you to map a light sensor reading to an exposure time.

It takes an object of the following format:

```js
{
  name: 'Direct sun', // the human readable name of the condition
  exposure: {         // a map of film types (ISO) to times in seconds
    400: 1.3,         // 400 ISO film needs 1.3s exposure time in direct sun
    800: 1.6
  },
  colour: {           // some fun colours for the UI (optional)
    start: '#f7ec86',
    stop : '#fdc753'
  },
  sensorRange: [0, 0.5] // min, max
                        // this lighting is selected when the sensor
                        // value is between 0 and just under 0.5
}
```

Add 2 lighting conditions:

    name: Direct sun
    ISO: 400, 1.3 seconds
    minimum light sensor: 0.6
    maximum light sensor: 1

    name: Indoors
    ISO: 400, 180 seconds
    minimum light sensor: 0
    maximum light sensor: 0.6

## Hints

You can pass an array of objects to `addLightingCondition()`.

The widget includes an array of default conditions, try `console.log(LightMeterWidget.defaults)`.

Don't forget, you can run your program in the browser using `ID=<your-id> lightmeter --port 11686 program.js` and loading the URL in your browser.