| width | 0 | 0 means max width. Look up your camera specifications to know what
 values are supported |
| height | 0 |  0 means max height. Look up your camera specifications to know w
hat values are supported |
| exposure | 10000 | **Night** time exposure in milliseconds. During the day, au
to-exposure is used. |
| maxexposure | 20000 | This is the maximum exposure for **night** images when u
sing auto-exposure. During the day, auto-exposure is always used. |
| autoexposure | 1 | Set to 0 to disable auto-exposure at **night**. Auto-exposu
re delivers properly exposed images throughout the night even if the overall bri
ghtness of the sky changes (cloud cover, moon, aurora, etc). When set to 1, *max
exposure* value will be used as the delay between timelapse frames. |
| gain | 50 | Gain for **Night** images. Varies from 0 to 600. During the day, g
ain is always set to 0 |
| maxgain | 200 | Maximum gain for **night** images when using auto-gain.|
| autogain | 0 | Set to 1 to allow auto-gain at **night**. This mode will adjust
 the gain of night images when the overall brightness of the sky changes (cloud
cover, moon, aurora, etc). **Avoid using autoexposure and autogain together** as
 it produces unpredicatble results (dark frames, but not always).|
| gamma | 50 | Varies between 0 and 100. This setting increases or decreases con
trast between dark and bright areas. |
| brightness | 50 | Varies between 0 and 100. This setting changes the amount of
 light in the image. |
| wbr | 53 | Varies between 0 and 100. This is the intensity of the red componen
t of the image. |
| wbb | 90 | Varies between 0 and 100. This is the intensity of the blue compone
nt of the image. |
| bin | 1 | bin 2 collects the light from 2x2 photosites to form 1 pixel on the
image. bin 3 uses 3x3 photosites, etc. Increasing the bin results in smaller ima
ges and reduces the need for long exposure. Look up your camera specifications t
o know what values are supported |
| delay | 10 | Time in milliseconds to wait between 2 frames at night. |
| daytimeDelay | 5000 | Time in milliseconds to wait between 2 frames during the
 day. |
| type | 1 | Image format. 0=RAW 8 bits, 1=RGB 24 bits, 2=RAW 16 bits |
| quality | 95 | Compression of the image. 0(low quality) to 100(high quality) f
or JPG images, 0 to 9 for PNG |
| usb | 40 | This is the USB bandwidth. Varies from 40 to 100. |
| filename | image.jpg | this is the name used across the app. Supported extensi
ons are JPG and PNG. |
| flip | 0 | 0=Original, 1=Horizontal, 2=Vertical, 3=Both |
| text | text | Text overlay. **Note**: It is replaced by timestamp if time=1 |
| textx | 15 | Horizontal text placement from the left |
| texty | 35 | Vertical text placement from the top |
| fontname | 0 | Font type for the overlay. 0=Simplex, 1=Plain, 2=Duplex, 3=Comp
lex, 4=Triplex, 5=Complex small, 6=Script simplex, 7=Script complex |
| fontcolor | 255 255 255 | Font color in BGR |
| smallfontcolor | 0 0 255 | Small Font color in BGR |
| fontsize | 0.7 | Font size |
| fonttype | 0 | Controls the smoothness of the fonts. 0=Antialiased, 1=8 Connec
ted, 2=4 Connected. |
| fontline | 1 | font line thickness |
| latitude | 60.7N | Latitude of the camera. N for North and S for South
| longitude | 135.05W | longitude of the camera. E for East and W for West |
| angle | -6 | Altitude of the sun above or below the horizon at which capture s
hould start/stop. Can be negative (sun below horizon) or positive (sun above hor
izon). 0=Sunset, -6=Civil twilight, -12=Nautical twilight, -18=Astronomical twil
ight.
| time | 1 | Replaces the text overlay |
| darkframe | 0 | Set to 1 to enable dark frame capture. In this mode, overlays
are hidden and the image is saved as dark.png by default |
| showDetails | 1 | Displays the exposure, gain and temperature in the overlay |

The second file called **config.sh** lets you configure the overall behavior of
the camera. Options include functionalities such as upload, timelapse, dark fram
e location, keogram.

| Configuration     | Default     | Additional Info |
| ----------- | ----------- | ----------------|
| UPLOAD_IMG | false | Set to true to upload (ftp) the current image to a server
 (website, blog, host, etc) |
| UPLOAD_VIDEO | false | Set to true to upload the timelapse to a server |
| POST_END_OF_NIGHT_DATA | false | Set to true to send some data to your server
at the end of each night |
| TIMELAPSE | true | Build a timelapse at the end of the night |
| KEOGRAM | true | Builds a keogram at the end of the night |
| UPLOAD_KEOGRAM | false | Set to true to upload the keogram to your server |
| STARTRAILS | true | Stacks images to create a startrail at the end of the nigh
t |
| BRIGHTNESS_THRESHOLD | 0.1 | Brightness level above which images are discarded
 (moon, head lights, aurora, etc) |
| UPLOAD_STARTRAILS | false | Set to true to uplad the startrails to your server
 |
| AUTO_DELETE | true | Enables automatic deletion of old images and videos |
| NIGHTS_TO_KEEP | 14 | Number of nights to keep before starting deleting. Needs
 AUTO_DELETE=true to work. |
| DARK_FRAME | dark.png | Path to the dark frame use for hot pixels subtraction.
 |
| DAYTIME | 1 | Set to 0 to disable daytime liveview. |
| CAMERA_SETTINGS | /home/pi/allsky/settings.json | Path to the camera settings
file. **Note**: If using the GUI, this path will change to /var/www/html/setting
s.json |

In order to upload images and videos to your website, you'll need to fill your F
TP connection details in **ftp-settings.sh**
```shell
nano scripts/ftp-settings.sh
## Dark frame subtraction

![](http://www.thomasjacquin.com/allsky-portal/screenshots/darkframe.jpg)

The dark frame subtraction feature was implemented to remove hot pixels from nig
ht sky images. The concept is the following: Take an image with a cover on your
camera lens and subtract that image later to all images taken throughout the nig
ht.

You only need to follow these instructions once.

Manual method:
* make sure config.sh has a DARK_FRAME configuration. Default is "dark.png"
* Place a cover on your camera lens/dome
* Set darkframe to 1 in settings.json
* Restart the allsky service: ```sudo service allsky restart```
* A new file has been created at the root of the project: dark.png by default
* Set darkframe to 0 in settings.json
* Restart the allsky service: ```sudo service allsky restart```
* Remove the cover from the lens/dome
![](http://www.thomasjacquin.com/allsky-portal/screenshots/keogram-annotated.jpg
)

A **Keogram** is an image giving a quick view of the night activity. It was orig
inally invented to study the aurora borealis.
For each image taken during the night, a central vertical column 1 pixel wide is
 extracted. All these columns are then stitched together from left to right. Thi
s results in a timeline that reads from dusk to dawn.

To get the best results, you will need to rotate your camera to have north at th
e top. That way, using a fisheye lens, you end up with the bottom of the keogram
 being the southern horizon and the top being the northern horizon.

Note that it will only show what happens at the meridian during the night and wi
ll not display events on the east or west.

The program takes 3 arguments:
- Source directory
- File extension
- Output file
## Startrails

![](http://www.thomasjacquin.com/allsky-portal/screenshots/startrail.jpg)

**Startrails** can be generated by stacking all the images from a night on top o
f each other.
The program takes 4 arguments:
- Source directory
- File extension
- Brightness treshold to avoid over-exposure: 0 (black) to 1 (white).
- Output file

Example when running the program manually:
```
./startrails ./images/20180223/ jpg 0.15 ./images/20180223/startrails.jpg
```