It is easy to rely on the ratings marked on different tools, whether it is a power supply, scale, or speedometer. However calibration is essential for any part that is relied upon either professionally or for a hobby. [Jeremy] wanted to see if his Lomography camera shutter really was only open for 1/100ths of a second when set to that. In order to test his rig, he set up an LED on one side of the shutter, and a high speed phototransistor to gauge the time spent open, using an oscilloscope to measure the time the reference point was pulled low. In his case, when the camera was set to 1/100, the shutter was actually open for closer to 1/150th of a second (the mean was 1/148ths of a second, with a standard deviation of 417 uSecs). This difference can make a large difference in picture brightness.
Be sure to check his blog for more pictures of the setup, as well as some useful part references and circuit diagrams.
[Toby] wanted to have a remote shutter trigger for his RICOH GR III camera. This brand doesn’t have a dedicated port for remote operation but a bit of research allowed him to build his own trigger. The camera’s USB port is used for triggering but not using the USB protocol. Instead, a pulse pattern on the 5V line identifies the half-press, full-press, and release states of the shutter button. From there it was just a matter of wiring up a circuit centering around an Arduino that leaves room for a lot of expansion into realms like photo automation.
If you’re on the fence about 3D TV and related technologies [Anton B.] might be able to help you decide. No, he’s not going to shove pamphlets in your face and explain why its the wave of the future. Rather, by showing the hack-ability (its a word) of 3D shutter glasses. A simple bridge of wire across specific contacts can ‘trick’ the glasses into only displaying only the left or right picture.
Wouldn’t that make it just a regular 2D TV again? Yes, that’s the beauty of it. Person A could be watching a completely separate movie pr0n than person B, but all on the same TV. Or two people could be playing a video game, without dividing the screen in half. The only problem is the current lack of software that can interlace movies/games, who’s up for writing some C++ this weekend?
[Pablo] likes to buy and repair broken cameras. When he was in need of a way to test the shutter speed, his brother came up with a great idea. Harvest the photo transistor from an old ball mouse. It turned out to be just as easy as it sounds. He plugs the circuit into some sound editing software to get the signal. We think this is pretty slick.
So you got CHDK working on your camera, and the histograms, raw image files, variable shutter speeds and other added functions are amazing, but stereo imaging is what you really want. If you have two or more CHDK-ready cameras, it’s cheap and easy to run StereoData Maker, a system that synchronizes the shutter and flash of multiple cameras.
The first step in getting SDM to work is installing the software on your SD card. You’ll need to find the correct version for you camera; a list is available on the main SDM page. If you are running Windows XP or Vista, run the installer in the zip file. Otherwise, load the files on the SD card and run the installer directly from the camera. Then decide whether this will be the right or left camera and repeat the steps for your second camera.
Next, you’ll need to prepare a switch unit, essentially a set of synchronized USB remotes. There are many ready made commercial units available, but building one on your own shouldn’t be much trouble, and a few ideas are provided on the SDM instruction page.
You’re basically ready to start shooting stereo images, just take a few test shots to get used to it and to customize the configuration on the cameras.