HDR Camera Control
Creating HDR(High Dynamic Range) Images requires multiple shots, typically more than the 3 shots usually supported by in-camera bracketing modes. The solution I've devised uses an NSLU2 running Debian, ptpcam(from libptp2) thttpd, a Bluetooth PDA with a Web browser and a couple simple CGI scripts to control a camera which supports PTP control of shutter speed and capturing images.
At present the system has been field tested and appeared to work ok. A BETA copy of the software and README is at: http://www.hdrfc.com/software
The script(on my Nikon D70) allows full control of shutter speed and ISO.(HDR bracketing is generally shuteer speed only as changing F-stop will change depth of field and the 'look' of the image.) Control is allowed in as small as 1/3 stop steps from 30 seconds to 1/8000 of a second. A more typical shoot from 30 seconds to 1/125 second with a 1 2/3 stop step takes about 80 seconds to shoot.
The power source is a standard commercial SLA(Sealed Lead Acid) battery connected to a 12V to 5V USB adapter and then a USB cable with an appropriate end to feed the NSLU2, I chose to leave the power button functional to allow the NSLU2 to cleanly be shut down in the field.
Feel free to email me: hdrfc -at- wormley -dot- com