[Gary Honis] has been modifying his Canon Digital Rebel XSi in order to do astrophotography. He previously removed the IR filter and replaced it with a Baader UV-IR cut filter that lets most infrared light through. However, in order to reduce noise in the pictures, he had to cool the camera down. He based the project on a peltier cooler that he salvaged from a powered beverage cooler. He made a small aluminum box and insulated it with styrofoam to hold the camera body. The peltier cooler was then attached on the side. It takes just over an hour to cool the camera down to 40 degrees, but the shots come out a lot clearer.
[Max Weisel] recently created a Peltier-based cooling/heating system that fits into a backpack. The system uses two Peltier units, each running at 91.2 watts, with computer heat sinks mounted on one side of the unit to dissipate the excessive amounts of heat generated. While he was originally trying to build a cooling backpack, the use of the Peltier units meant that the cool side would become warm when the direction of current was switched, meaning that the backpack could become a heating backpack with the flip of a switch. In order to power the two Peltier units, he uses two 12v motorcycle batteries, weighing in at around 5 pounds each. While this backpack might be a little heavy for your back, it looks promising for anyone who needs to keep things cool (or warm) on the go.
Here’s a good 4th of July project: Chris Garrison sent in his portable peltier based beer cooler. He saw a cheap peltier junction for sale and decided to build a mini-fridge. It holds 14 cans and is portable enough to place wherever needed. He does comment that his power supply isn’t quite up to snuff, but it does a passable job for only spending $35 on the project.
i found this link in my inbox, courtesy of j. peterson. we’ve posted a peltier beverage cooler before, but i think this one deserves mention as well. it hasn’t had the finishing touches, so it’s not as pretty yet. however, this one does come with a digital temperature readout. more importantly, it’s big. you could countersink a couple of these babies into your dining room table and start living the 21st century good life, as imagined way back in the mid-1900s.
just think, your home of the future, complete with soda-cooling, plate-heating countertops and a kitchen computer.
using rechargeable batteries, a 1u cpu-fan, a 118w peltier cooler, a cold-plate and some pretty hacked up pc parts, you too can make a beer cooler and keep that brew in the sun. not that you’d really go outside that much if your hobby was hacking up pcs to make coolers, i haven’t been outside in weeks.
We recently reported on the amateur scientific work of Forrest Mims. Forrest is somewhat unique in being an amateur scientist who has consistently published his work in leading scientific journals. One area of scientific investigation has however attracted amateur scientific contributions of the highest quality almost since its inception, amateur astronomy.
You’ve likely heard of amateur astronomers like David Levy co-discoverer of the Comet Shoemaker–Levy 9 comet, and citizen science projects like galaxy zoo. But the history of amateur astronomy goes back far further than this, in fact as far back as 1781 William Herschel discovered the planet Uranus while employed as a Musician. Another entertainer of sorts, 1930s British comic actor, Will Hay, also made significant contributions discovering a “Great White Spot” on Saturn in-between films roles. Will was an avid amateur astronomer who regularly published his observations.
His belief that astronomy allows us to see humanity’s place in the universe in its true proportion led him to claim “If we were all astronomers there’d be no more war”.
While Will recorded his observations, hand drawn, in a log book. Modern astronomers digitally image the night sky. Digital cameras are of course optimized around the human visual system (as we recently discussed) making them less than ideal for astrophotography. Hackers have therefore made a number of innovations, one of the more audacious being the removal of the Bayer filter: