Hello, sky!

The skycam at FLEXLAB captures an HDR image of the sky every five minutes. In addition to documenting sky conditions, the images can be used in Radiance to simulate the sky luminance for a specific time.

About LBNL's SkyCam

LBNL's sky camera resides on top of the FLEXLAB's high-bay testbed, with a beautiful view of the San Francisco Bay. Terrestrial Light, a Berkeley-based startup, designed and manufactured the HDR sky imaging system we use at FLEXLAB.

Every five minutes skycam takes bracketed exposure images of the sky. These images are combined into a single high dynamic range (HDR) image that encapsulates the entire luminance range of the sky (save the luminance of the sun). The HDR image is calibrated using global irradiance and illuminance measurements from sensors mounted alongside the skycam.

The sky HDR images can be used to infer the luminance seen through a window, or can be used to accurately replicate the sky in a Radiance daylight simulation.

Sample Data

Morning clouds burn off by 7:20. Clear sky for the majority of the day. Clouds and fog return at 18:00

Download zip of sky HDR images (544 MB)
Download csv of measured data (17 KB)

Light cloud cover persists until 3:00pm. Clear sky for the rest of the day.

Download zip of sky HDR images (548 MB)
Download csv of measured data (18 KB)

Overcast all day with a few bright spots from 10:00-11:00.

Download zip of sky HDR images (544 MB)
Download csv of measured data (17 KB)

Scattered clouds between 10:00 and 11:45. Clear sky for the majority of the day.

Download zip of sky HDR images (440 MB)
Download csv of measured data (14 KB)

Light and patchy cloud cover persists all day.

Download zip of sky HDR images (441 MB)
Download csv of measured data (14 KB)

Overcast skies all day long.

Download zip of sky HDR images (433 MB)
Download csv of measured data (14 KB)

Clear sky all day. Merry Christmas!

Download zip of sky HDR images (345 MB)
Download csv of measured data (11 KB)

Patchy clouds most of the day, Clear sky from 3:30pm until sunset.

Download zip of sky HDR images (366 MB)
Download csv of measured data (11 KB)

Overcast and raining all day (sorry for the water drops).

Download zip of sky HDR images (365 MB)
Download csv of measured data (10 KB)

Contact

LBNL's FLEXLAB is pleased to offer data from our sky camera to other researchers and practitioners.

Contact Terrestrial Light to discuss their product and its capabilities, including cloud forecasting.

For data from FLEXLAB's sky camera:

Ari Harding
LBNL

AHarding@lbl.gov
(510) 495-2566


Anothai Thanachareonkit
LBNL

AThanachareonkit@lbl.gov
(510) 486-5991
For info about sky cam contact:

Chris Humann
Terrestrial Light

chris@terrestriallight.com
(510) 843-5821