The All Sky Camera

The All Sky Camera looks up from the village of Bourn in Cambridgeshire, UK. It's fully weatherproof and images the sky 24/7. You can see clouds, stars, sun, contrails, clouds, moon, rain, clouds, and their movements across the sky. Clouds from the left, clouds from the right. Clouds from three different directions simultaneously. Did I mention the clouds? The time-lapse cloudscapes can be facinating and beautiful, if somewhat frustrating for astronomy.

The Sky Now

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Last Hour Animation

The all sky cam animated loop page displays a loop of the last hour's worth of images. Each loop takes around 6 seconds to display and a new image is added into the loop once a minute. Useful for keeping track of the state of the sky as the night progresses.

Timelapse Movies

Movies are captured at one frame per minute, and played back at 10 frames per second. You see an hour of sky every 6 seconds. Click on the links below to view the movies.

Last Night
(6pm yesterday to 6am today)
(midnight to midnight)
Split Day
(midday to midday)


The movies are encoded in H.264/MPEG-4 AVC format. I you have problems viewing these movies in your standard media player then I recommend the free VLC Media Player (versions for Windows, Linux and Mac are available). Windows XP based Media players may require a codec to be installed to view the movies. I recommend the free Combined Community Codec Pack (CCCP) for this purpose.


The current imaging system consists of a Mintron 12V1-EX integrating colour video camera, coupled with a Rainbow L163VDC4P fisheye lens. In low-light situations the camera internally combines multiple frames (up to 128) to image at star-light illumination levels. In addition we average eight of these frames together offline to further smooth the image. To better capture transient phenomena such as meteors, pixels above a certain brightest level in individual frames are preserved and not averaged. At night the camera appears to be slightly more sensitive than dark adapted eyes, and is an excellent way of picking up high cirrus that would not normally be easily visible. The camera is housed in a weatherproof canister previously used to house a old lidar based airport cloud level monitor. The canister window has a tendency to dew-up during periods of high humidity. This needs to be fixed by adding a better window heater at some point. The camera's also exhibit a few bad pixels, which show up as "stars" that don't rotate across the screen.

The camera's video output is fed into an Eptascape ADS-200 video server. The box provides a live feed to any computer on the LAN. In addition to the all sky cam, the video servers also support an observatory monitoring camera and a western horizon facing "sunset" camera - the feeds for which are not directly accessible via the web.

Camera settings are controlled via an RS485/RS232 converter camera-to-PC connection and Mintron's camera control software (63V5H). The software requires RTS/CTS and DTR/DSR/DCD lines to be tied together (a Null Modem conversion), can only be used on the lowest numbered COM port, and then only COM1-3.

A Linux based server captures individual images from the video server, integrates eight frames together per minute to help reduce image noise, and creates and stores the various time-lapse movies. The heavy lifting is done with mencoder, and the system is glued together with simple shell script cron jobs.


The All Sky Camera started life in May 2008 and has been faithfully recording the sky, with the odd interruption due to hardware failures, ever since. The observatory's "SkyEye" server holds a publicly accessible archive (see below).

The hardware and software has gone through various changes, mainly due to hardware failures. The original imaging system consisted of a Mintron 12V6HC-EX integrating mono video camera, coupled with a Fujinon YV2.2x1.4A-SA2 fisheye lens. This original mono system had to be replaced after the camera failed. The new colour system is less sensitive, but better illustrates the level of local light pollution - showing differences in colour between low and high clouds. Similarly the original video server was based on the Aviosys 9100B-RS upgraded with the Yoics firmware hack.

Early experimental nighttime timelapse movie using Canon 20D DSLR and Peleng Fisheye Lens.


All Images and Movies from May 2008 onwards are available to browse and download. All the timelapse movies are stored as AVI files in this directory. You can also find the individual minute-by-minute frames (that the movies are constructed from) in sub-directories organized by year.

All timestamps are UT/GMT. Dates used for movie filenames and directory organization are in ISO date format: [year][month][day].

Current movies and images are orientated North upwards and West to the right. Movies prior to 20090630 are oriented with E up and N right. Early images are from a monochrome camera, Between July 2009 and March 2010 a colour camara ran in parallel with the monochrome, and all images after that are colour only.


Similar setups, useful information, and professional observatory all sky cameras: The Cambridge Institute of Astronomy All-Sky Camera, University of Herts Bayfordbury AllSky Camera, MMTO Sky Camera, Cloudbait Observatory, JAT Observatory, MASCOT (ESO Parnal) and LasCam (ESO La Silla).

The All Sky Camera is your prototypical Tim and Paul co-production.

  Site contents and all images are Copyright © Paul Beskeen