...astronomy is so visually appealing as well! Colorful stars, wispy, ethereal nebulae, galactic vistas sprawling out across our telescopes… it's art no matter how you look at it. And our techniques for viewing the heavens gets better every year; our telescopes get bigger, our cameras more sensitive, and our robotic probes visit distant realms, getting close-up shots that remind us that these are not just planets and moons; they're worlds.
All the buzz about the movie Avatar has me reminiscing about the Optics issue of MAKE. In Volume 14, award-winning filmmaker and digital artist Eric Kurland showed us how to build a 3D dual-camera rig, and make a live 3D video monitor and PSP stereoscope to go with it. Here's Eric's intro and backstory, and at the end a link to the project shared with you in our Digital Edition. You can also still pick up a physical copy of Volume 14 to add to your collection over in the Maker Shed.
Homebrew Digital 3D Movies Build your own stereo video camera and 3D viewer. By Eric Kurland
I have two eyes. And because of that simple fact, I also have stereopsis, the ability to perceive depth. When I was about 7 years old, I gazed into a View-Master toy and saw an amazing three-dimensional picture, and I was hooked. Today, I create 3D videos, using various homebrew camera rigs and displays. I'll introduce you to a few of my devices, but first, a quick history lesson.
In 1838, British scientist and inventor Sir Charles Wheatstone theorized that seeing with two eyes together is what allows us to see in 3D. Wheatstone deduced that each eye observes a slightly different view of the world, and our brain fuses these two perspectives together, interpreting the parallax differences as depth. He called his discovery stereoscopic vision (literally meaning "to see solid") and built an optical device, the stereoscope, that allowed three-dimensional viewing of pairs of drawings.
With the invention of photography, and later cinema, real-life images could be captured with two lenses and viewed in 3D. The popularity of stereoscopy has persisted over the years. In the 1890s, arcades offered 3D peep shows as entertainment, and the handheld stereoscope was a common item in home parlors -- the TV of the Victorian era. The 1950s and 1980s both saw 3D movie "booms" come and go, due to the technical limitations of the times. And currently, in the age of digital video, stereoscopic 3D is seeing a major rebirth.
My own foray into 3D video began a few years ago, after I attended the monthly meeting of the Stereo Club of Southern California. Many of the photographers at the meeting had pairs of digital still cameras mounted side by side for shooting 3D photos, and it occurred to me that I could build a similar hand-held rig for use with small camcorders.
Shooting 3D Starting with a pair of Sony Handycams, I set out to build a stereoscopic rig. My plan was to make the distance between the lenses, called the interaxial, equal to my interocular, or the distance between my eyes. This would give a natural-looking 3D depth to my footage, and would allow me to view 3D while shooting, just by looking through both camera's viewfinders. Putting the lenses so close required removing the hand strap from the left camera.
I attached the cameras to a metal bar using quick-release mounts for easy removal, in order to access the tape and battery compartments. I fashioned a bracket from some spare parts to hold both cameras securely at the top and keep the lenses aligned. Inspired by director Mike Figgis' steering wheel-like camera stabilizer (the "Fig Rig"), I bolted together a pair of photographic flash bars with handgrips, salvaged from a flea market dollar bin, and created a "handlebar" stabilizer. This allows me full mobility with the rig, and puts the center of rotation between the two cameras.
To control recording, I use a device called the 3D LANC Master. Developed by Dr. Damir Vrancic of Slovenia, the 3DLM connects the cameras via the LANC ports and provides simultaneous control of most camera functions. It also keeps the video recording in sync by continuously polling the timing frequency of one camera, and adjusting the frequency of the other up or down to prevent drift. This is very important when shooting 3D, as any time disparity between the camcorders will result in nonmatching left and right views. Schematics and software for the 3DLM are open source under a GPL and are available for free.
Viewing Live 3D With my camera setup complete, my next task was to build a portable stereoscopic video monitor, so others could watch live 3D during shooting. In movie theaters, stereopsis is achieved by projecting left and right images through two oppositely oriented polarizing filters onto a reflective screen. By viewing through 3D glasses made from matching polarizers, each eye sees only the corresponding projection. I decided to use the same principle for my monitor.
I started with two small LCD monitors capable of showing NTSC video, the kind that are strapped to the back of car headrests. The video output from each camera is input to one of these monitors. Because LCDs have a polarizing layer, these displays appear black to one eye and visible to the other when viewed through polarized 3D glasses. I found that the monitors had a clear plastic protective sheet glued over each LCD. These had to be carefully peeled up and removed, as they were depolarizing the light from the screens.
On one display I needed to flip the picture horizontally like a mirror image, so I opened the case and wired pin 62 of the PVI-1004C LCD controller chip to ground. I attached the LCD displays to each other at a 90° angle, their screens facing inward, and mounted a piece of half-mirrored glass between them. This glass superimposes the reflection of one screen on top of the other. When viewed through polarized glasses, the reflected image and its polarization are reversed, each eye sees only one screen, and we have live 3D video of whatever is being shot.
Editing 3D Shooting with two cameras creates two individual video files, which are digitized into the computer for editing. First, I use the freeware application StereoMovie Maker, developed in Japan by Masuji Suto, to correct misalignments in my footage, which can cause eyestrain.
In StereoMovie Maker, I am able to load both the left and right videos and visually transform, scale, and rotate them while viewing in 3D with anaglyph glasses. Anaglyph is the method in which the two pictures are combined into a single image with one eye in red and the other in cyan. Primarily used in printed stereoscopy, anaglyph also provides a means of viewing depth on any computer screen using inexpensive red-cyan glasses.
Once satisfied with the alignment, I save my videos as a single file, formatted side-by-side in a split screen, and twice as wide as a normal video picture. I prefer this format, as it ensures that the two views always remain in sync throughout the editing process. The footage can be cut together in any standard video editing program. My system is PC-based, so I use Adobe Premiere, but the same techniques would apply to a Mac Final Cut Pro system. One thing to take into account when editing 3D is that drastic depth changes between consecutive shots can cause eyestrain.
To watch my completed movies in 3D, I use Peter Wimmer's excellent Stereoscopic Player program, a full-featured media player for stereo video files that converts on-the-fly to the many different viewing formats required by stereoscopic displays and projectors. Both Stereoscopic Player and StereoMovie Maker are Windows-only applications, but they will run on Intel Macs running Windows.
Showing 3D In order to show 3D video to audiences, I have a dual-projector setup, just like the 3D theaters of the 1950s, using two projectors, polarizers, and a silver screen. The only real difference is that my projectors are small DLP digital models, and my "film" is a file played back by computer. This arrangement works well for large audiences, but I also wanted some method of carrying my 3D movies with me to show at a moment's notice -- a portable stereoscopic media player.
The Sony PSP looked like it would be the answer. The PSP can play MPEG-4 files from a flash memory card and it has a nice, wide screen -- wide enough to hold side-by-side-formatted left and right images.
In fact, the PSP is just about the same size as a standard vintage stereo card. I decided it would be cool, and somewhat steampunk, to mount a PSP onto a circa-1904 stereoscope.
As luck would have it, the PSP fit almost perfectly between the two card-holder wire clips. I didn't want to physically alter the viewer, as it's an antique, and I wanted the PSP to be removable, so I cut two loops of thin velcro strapping, just long enough to go around the PSP and hold it firmly to the slide bar.
To get my videos onto the PSP, I converted them to x264 compressed MPEG-4 files at the PSP's screen resolution of 480x272 pixels, and copied them to a PSP Memory Stick. Sure enough, side-by-side video files played on the PSP and viewed through the stereoscope's eyepiece are seen as a single three-dimensional movie.
The whole setup works perfectly. I can easily carry around a bunch of my homemade 3D movies on a Memory Stick in my pocket, and quickly show them to people through the "PSPscope" -- a perfect marriage of 19th- and 21st-century technologies.
One of the CES hardware announcements that looks interesting to us is D-Link's Boxee Box, a media player built around the open/closed source Boxee application (Boxee is a "fork" of the open source XBMC media center software, with some closed, proprietary code bolted on). The Boxee Box will play Adobe Flash 10.1, H.264 (MKV, MOV), MPEG-4, Xvid, Divx, and other video formats, and will feature built-in 802.11n wireless. The Box can play 1080p video from locally-stored content and stream HD video content over the net. It has one HDMI connector, two USB 2.0, Ethernet, plus composite audio, and S/PDIF output. There is no internal hard drive(!) but there is an SD card slot.
Announced today is the fact that the Boxee Box uses the NVIDIA Tegra 2 (T20) system-on-a-chip. The T20 is built around a dual-core ARM Cortex A9 CPU which can hopefully deliver some of the graphics power for which NVIDIA is known. A lot of people have installed the Boxee software on other computers and media player hardware, and have developed plug-ins for the software. It'll be interesting to see what they'll do with the Boxee Box, which is allegedly going to sell for under $200.
(And, BTW: You have NOT skipped a dose of your medication. The Boxee Box really does look like it's melting into the shelf it sits on. Hey, who said that boxes have to be rectilinear? Not really sure what to make of it. It's different, I'll give it that...)
I just found out that Shapeways is offering full color 3D printing using a Zcorp 650 3D printer. This isn't painted, but rather embedded in the materials (there are binder, powder and five inkjet color cartridges used at print time). Haven't tried it out yet, but it looks pretty good. The alien here is about $70 and stands 15.5cm high.
From the Shapeways site:
The process itself works by a printing head incredibly similar to a inkjet printing head depositing a powdered plaster material and also adding color to the print. The material used is a powdered plaster. Traditional issues with the Zcorp process are flaking, lack of structural strength and a 'washed out' look.
To combat this lack of strength Shapeways uses a rapid thermoset composites. These add significant strength to the 3D printed parts as compared to traditional Zcorp finishing techniques such as infusion with cyanoacrylate (Super Glue). Additionally a unique machine is also used to apply the composite materials using a resin infusion method. Compared to traditional Zcorp parts the Shapeways Full Color 3D printed models and parts will be stronger and have brighter clearer colors.
If he wins, Matt will use the grant money to build his "Anywhere Organ," a demountable, portable pipe organ which he hopes to take on a tour of public installations across the country. You can read about (and vote for!) Matt's proposal here.
As I write this (11am CST) I'm repeatedly hitting Apple-R on my keyboard to refresh my browser. That's right, I'm one of the thousands of giddy electronics fans trying to cash in on SparkFun's Free Day. Last I saw, almost 92% of the funds remain, mainly due to people DDOSing the server with their frantic reloads.
OK, hands off the keyboard. Let's take a deep breath, step back a moment and consider a question: in the final analysis, is this $100,000 free-for-all -- the nerd equivalent of 10,000 soccer moms battling over a limited number of Teddy Ruxpins on Black Friday -- really a good idea for SparkFun? Ultimately will it help or hurt them? I asked two hardware hackers, Garrett Mace and MAKE's own John Edgar Park, to weigh in. Bear in mind that they wrote these opinions last night.
First, Garrett Mace says negatory, bad idea:
It just seems like a bad move for SparkFun. More of a risk, actually. They are definitely getting a lot of publicity from Free Day, but I don't know if it will outweigh the negatives. Their site has been slow all month, bad for any online business. They're losing $100,000 of income, or about $20,000-$50,000 in costs. About 1,000 people will get their free stuff, but many thousands more will fail to do so, for various reasons. The people who didn't get their free stuff will somehow feel cheated, either by SparkFun or by the ones who did get the free stuff. There will be hundreds, maybe thousands of emails to SparkFun support complaining, or begging for special consideration because a computer crashed, the power went out, etc. And I think that many of the lucky 1,000 will be those only looking for something free, instead of those who would fully appreciate and use the hardware. I expect that a lot of the free stuff will end up in the bottom of a drawer forever. There are definitely 1000 electronic hobbyists out there who would truly appreciate SparkFun's gesture and would put the hardware to good use, but there's no way to select for them. I think SparkFun would get much closer to what they're trying to accomplish here if they held smaller giveaways throughout the year, with a more selective approach (design contests, quizzes, etc). Regardless of what happens, we're not going to hear any misgivings from SparkFun after the fact...they have to play it off as a grand event now that they've committed to it, so we'll hear upbeat reports with lots of words like "amazing", "exciting", "overwhelmed", "community" and so on.
I hate to be negative, since the actual intention behind the idea is great. I'm just speaking from experience seeing other giveaways; hackaday and "i want this book", the Woot.com Bag Of Crap, etc.
For the counterpoint, J. Edgar says yea:
SparkFun's Free Day is a great idea for a number of reasons. Foremost, they're getting a ton of free publicity for it. I won't claim to have run any numbers, but I'd guess that this kind of advertising is worth thousands or tens of thousands of dollars (remember, $100K of merchandise will cost them between $25-50K at cost, and they ain't paying for shipping). Why is this stunt worth so much? Because it's not limited to a single ad in a few print publications or banners on websites. It's the juicy kind of advertising that's hard to buy; it's buzz. People are tweeting about it, blogging about it, excited about it. Not only are the major hacking/building/making sites writing about it, but so are the deal sites, the forums, and so on. They've even got 274 comments on their original blog post announcing this -- when people make the effort to become part of the conversation you know they'll remember you the next time they need to buy a breakout board.
Next, their stated reasons are sound. They want to stress test their new servers. This'll do that. They want to engender good will to their customers. Engendered. They have excused themselves from shipping it all immediately, so they won't need to hire extra hands or crush the existing staff.
Sure, most people will be turned away at the door, and some people will send email to complain about that, but in the long run this is a terrific move. SparkFun has great products and a winning personality, so anything they can do to get their name out to a wider audience will benefit them in the end. [Full disclosure, SparkFun distributes ScrewShield kits, of which I'm a co-creator.]
What are your thoughts, readers? Did you successfully battle your way to the checkout window? What loot did you score or not score? Leave your comments but please keep them rational and courteous.
Regular parabolic mirrors are great for concentrating sunlight for solar heating, however they are bulky and can be difficult to repair. That's where Dominic Wanjihias' flat parabolic mirror comes into play. He replaced the traditional curved mirror with a series of thin strips of mirror, making what appears to be a Fresnel reflector. It's a pretty simple concept, but has a bunch of practical advantages:
It is very cheap,
It can be quickly dismantled or moved,
It is easily transportable as it can be carried flat or in a tube,
It is easily repaired if broken as the individual mirror pieces can be replaced (rather than having to fix or replace an entire parabolic mirror).
Pardon me while I go chemistry geek. It has recently come to my attention that Leo Gross and co-workers at IBM Research in Switzerland have developed a special atomic-force microscopy technique that can image actual molecules with enough resolution to "see" individual bonds and hydrogen atoms. Shown uppermost is a computer-generated model of the pentacene molecule, and below it, an actual image from the microscope. The microscope's probe is tipped with a single molecule of carbon monoxide. Unbelievable.
We ironed on conductive fabric pads on different parts of the gloves, and read them off like a multiplexed keypad. The pads on one glove are the rows and the pads on the other glove are the columns, and strobing rows and columns sees what combination of pads were connected to each other). The LilyPad then figures out what gesture is being made and transmits a number through serial to a Processing program which displays the gesture on the screen and checks for the correct pattern.
Emotiv's EPOC neurosensor headset offers the ability to convert brainwave signals to keystrokes on a PC. Tron of Illuminated Sounds recently acquired an EPOC and posted this quick demo of the interface triggering beats in Ableton Live -
It should be interesting to see how much the response time can be improved given a bit more practice/experience with the device. Once that's covered we can hopefully move on to the much-promised flying cars.
Creepy-cool snakey water robot goodness. Not much info about the maker, here; all I know is that the video was taken at the Odense RoboDays festival in the summer of 2007. If you know whodunnit, feel free to enlighten us in the comments. [via Boing Boing]
We have the Make: Electronics toolkit back in stock! Do you want to learn to solder? Not sure what tools you need? We took the trouble out of searching for all the right tools for the job. This kit includes everything you need to get started in the wonderful world of kit making! We even included your first kit, the WeeBlinky, and a Maker's Notebook to help you document your next project.
Features
(1) 30 Watt adjustable soldering iron
(1) Deluxe Solder Stand & sponge
(1) 1/4 lb Spool of rosin core solder .031" (60/40)
Check out Elisa Strozyk's awesome pixelated textiles made with castoff wooden veneering.
The wooden textile intends to look at the new ways wood can be manipulated from its hard physical property to a fluid form when combined with fabric. Providing flexibility to wood allows us to connect with it in new ways. Utilizing wood veneers once considered waste and re-purposing them through hand and laser cut isosceles, she is able to leverage the hard properties of wood and give them a fluid framework to create an innovative textile. Her process gives the textile strength and flexibility.
I love how our pals over at iFixit are always the first in line to buy new gadgets as they come to market, so they can race them back to the shop to take them apart and find out what makes them tick. Their excitement and curiosity is almost palpable, and of course, we all benefit from what they find. Kyle and company just plunked down a princely 530 bones for the exploratory thrill of field-stripping the Google Nexus One.
The Nexus One, manufactured by HTC, is the latest and greatest Android phone. It sports:
* A 1 GHz Qualcomm (QCOM) Snapdragon processor. * A 3.7" 480x800 widescreen WVGA AMOLED display. * A 5MP digital camera w/ LED flash that also records .mp4 video. * 802.11n wireless capability for when you can't depend on 3G. * 7 hours of 3G talk time from a removable 3.7V, 1400 mAh lithium battery.
One of the CES hardware announcements that looks interesting to us is D-Link's Boxee Box, a media player built around the open/closed source Boxee application (Boxee is a "fork" of the open source XBMC media center software, with some closed, proprietary code bolted on). The Boxee Box will play Adobe Flash 10.1, H.264 (MKV, MOV), MPEG-4, Xvid, Divx, and other video formats, and will feature built-in 802.11n wireless. The Box can play 1080p video from locally-stored content and stream HD video content over the net. It has one HDMI connector, two USB 2.0, Ethernet, plus composite audio, and S/PDIF output. There is no internal hard drive(!) but there is an SD card slot. 
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