Dome1 was our first “quarters” split portable RTI imaging dome produced in the AHRC project for the Ashmolean museum in Oxford. It used 76 3W white LEDs (~400 lumen Bridgelux BXRA-N0402-00000 LEDs) driven with a constant current source. A grid cross-over technique is used to power each in turn using our custom usb controller, plus a Nikon D3x camera controlled via its USB connector. These LEDs have a “neutral white” colour temperature of around 4100K. We rely on a short (< 5s) exposure to avoid heating effects and the need for a heatsink.
- Here is Dome1 being tested in Oxford
You can see a time-lapse video of the dome construction on Vimeo. The two domes of this design are in Archaeology in Southampton and in Oxford. The camera frame is the first version and not as stable as the one designed for domes 4,5,6.
This is the spectrum of the LEDs – showing the characteristic blue spike around 450nm (taken from datasheet).