Recently at a Community Science Workshop network training/skill swap day I was asked where we find our ideas and our project materials. Thinking about this I realized it was quite a long list and that there was no way I was going to remember all the good ones in that conversation. So in this post I will try to provide a more complete list of what resources we use on a regular basis.
American Science and Surplus
•A good source for cheap optics, lab ware, electromechanical parts, and a wide variety of hardware and equipment. While their inventory changes over time it is relatively stable.
• Very cheap high quality optics, a great place to go if you wanted to get the components for a telescope for under $40. The down side of Surplus Shed is that its almost completely surplus, so if you find a cool lens today it might not be in stock in the future so plan accordingly.
• This site has a fairly complete selection of electronic components at reasonable prices. Their LED assortments are a particularly good deal. They also have some unique optical components though they're not as cheap as some other sites. Goldmine seems to stock the same items consistently from my experience.
• Another electronics surplus site with somewhat of a wider selection of parts and a fairly stable inventory. They have a lot of useful electronic accessories such as cables and housing for projects, as well as a good selection of things like motors and LEDs.
• Uline sells packaging supplies for shipping, we order through them when we need a large number of identical cardboard tubes, while not the cheapest they do deliver very fast and can provide long tubes at sub dollar prices as long as you get 50 or more. When you consider you can usually get 5 or 6 projects from one long tube the price is actually quite affordable.
Bay Area Specific:
East Bay Depot for Creative Reuse 4695 Telegraph Ave. , Oakland (at Telegraph and 47th, near where Shattuck hits Telegraph)
• This store stocks many discarded but still useful consumer materials. Things like cookie tins, cardboard tubes, bottles, yarn and fabric can be found there. They also seem to have a lot of old media, slides records, tapes and occasionally microfiche.
Scrap 801 Toland, San Francisco (entrance on Newcomb between Toland and Selby streets)
• This place has a very similar variety of items as the East Bay Depot, with more craft materials and less media.
Urban Ore 900 Murray Street, Berkeley (near Ashby and 7th)
• A huge somewhat addictive junk store, they consistently stock building materials like PVC pipe, and 2X4'' and will sell you a 10' length for about a dollar. They also stock a wide but ever changing variety of hardware, tools, electronics and furniture.
Science education specific:
• RAFT has a large searchable archive of activities ("Idea Sheets") which are often a good starting point for planning or expanding an activity.
• While Instructables can have somewhat of an annoying format, it does archive hundreds of thousands of projects. Browsing randomly or searching for a specific idea is often fruitful.
• Although Make Magazine has many projects that would financially and technologically be inaccessible to the Discovery Center and organizations like us, there are also many good simple ideas on the Make site which are worth taking a look at.
Anchor Optics: vintage optical projects
• A series of simple optical projects in pdf format, originally published in the 60's and 70's still have a lot of relevant information.
Toys from Trash
• This site contains many simple and incredibly inexpensive projects that address various aspects of physics.
Exploratorium Science Snacks
• The Exploratorium Science Snack site has many simple activities which clearly and concisely illustrate basic scientific principles using every day materials. Its valuable both a a conceptual reference library and as useful inspiration and add ons for science activities. There is book version of these activities, The Exploratorium Science Snack Book (Paul Doherty), I believe there are currently 2 additions.
• An offshoot of the Exploratorium's Learning Studio, PIE has many activities/experiments that merge art and science in an intuitive way to further understanding of both. Looking at the "PIE work" and "Idea Library" sections is definitely worthwhile.
Having a good physics text book (which you can understand) is also a very useful resource as you can use it to reference the science behind a project.
Some people will probably wonder why I added the following references to the list as they appear divergent, but looking at professional design work especially that which focuses on materiality and structure can be informative. The trick is filtering it out from all the cool but less applicable design out there.
•A major American industrial design magazine cover all aspects of industrial design. Alot of this is not very applicable but then there are things like this interspersed which could be the basis for an interesting activity on structure using easy to find parts (think cardboard and index cards).
NOTCOT has collected a huge number of interesting design projects from various sources. Again the trick is separating that which is generally interesting from that which is relevant to science education.
I searched "cardboard" or "light" and got some applicable results.
Inna Alesina, Ellen Lupton, Exploring Materials: Creative Design For Everyday Objects. New York: Princeton Architectural Press, 2010.
•This book shows many examples of objects created by manipulating materials and then goes on to explain simple techniques to replicate the manipulation processes. Making objects out of paper, plastic metal, wood and fabric are covered. I think the plastic forming techniques are particularly interesting and informative.
I hope this is informative,
Monday, January 16, 2012
• Foamcore: one piece big enough to fit the viewer template (about 10''x4''), a 4''x5'' piece to mount the images, an 2''x2'' right triangle.
• 2 small lenses (we used surplusshed.com Item #:L10039: RECTANGULAR PCX 22MM X 20MM X 80MM FL)
• Hot glue gun
• Utility knife
• Metal ruler
If you're just making one viewer transfer these dimensions directly onto a your foam core, if not you may want to make a template like this so it can be traced onto multiple pieces of foamcore. Note that the two unmarked dimensions for the nose hole are approximately 1'' at the top and 1.5'' at the bottom. After you transferred the pattern cut out the nose and eye holes and score the hinges between the front and side flaps.
Next fold up the side flaps and glue in the 2''x2'' triangles to hold them in place.
While you can put the the triangles either on the top or the bottom of the viewer we found it lets in more light if you put the triangles on the bottom and then trim off points where they protrude into the nose hole.
After the flaps are in place and the triangles are trimmed take the lenses with the curved side down and glue in place. As two sides are blocked by the triangles and the side flaps, its easiest to glue the lenses only on the top and inner sides, like so:
Take your stereograph and glue it on to the 4''x5'' foamcore piece, glue stick or double stick tape works best. If you have multiple stereographs you can put one on each side of the mounting foamcore. Finally, punch a hole in the image mounting foamcore and one of the side flaps and tie them together with a fairly long piece of yarn. To use the stereoscope hold the viewer up to your face (with the flaps away from you) and slowly bring the stereograph plate towards the side flaps off the viewer. The 3-D image will come into focus when the stereograph plate is sitting on the viewer side flaps, you can also place the stereograph plate on a table and then slowly bring the viewer down to the image.
Things to Do and Notice:
A stereoscope is a means of simulating a 3 dimensional image with two 2 dimensional images. A favorite form of Victorian entertainment, stereoscopes take advantage of the way the brain processes images using the slightly different points of view from our 2 eyes. To illustrate how the brian uses two eyes to perceive depth simply hold you finger in front of your face and slowly move it away while opening and closing you right and left eye repeatedly. When your finger is near your face it will appear to jump significantly between the perspective of the right and left eye. As you move your finger away it will appear to jump less and less.
To make this effect more dramatic have a friend slowly walk away from you while alternately opening one eye then the other. For most people the view from one eye to another will appear not to jump from right to left significantly when your friend is more than 20 or 25 feet away. While our brains continue to use stereopsis beyond this point, things like geometric perspective (that distant objects appear smaller and straight appear lines to travel to vanishing points) and atmospheric perspective (that distant objects appear less detailed) play a larger role.
Where to Get Stereoscopic Images:
Historic stereoscopic photos are available in many places on line, searching for "stereoscope" "stereograph" will generate many interesting results. These historic photos will work fine with this viewer as long as you scale these photos to fit the viewer. Alternatively you can cut the stereographs in half and slid the two halves over each other until the illusion is formed, the trick is lining up the center of each photo approximately with the center of the viewers' lenses. You can also make stereographs yourself using either two cameras or a system of prisms or mirrors to get two perspectives from one camera.
After looking looking at http://www.anchoroptics.com/documents/ "Homemade Camera Stereo Adapter" article and this Instructables article, we made this stereo camera adapter allowing us to make stereographs with one camera.
Here's a view looking through the back of the stereo adapter, while it's fairly crude it does create very useable stereographs. Essentially the adapter is 2 short periscopes on their sides, with the 2 central mirrors butted directly against each other. The centers of the adapters two outer mirrors are about 10'' (254mm) apart (this is the base length) so the stereographs it produces have an exaggerated perspective as human eyes are typically just 60-65mm apart. Typically a 1:30 ratio of base length over the distance to the nearest object is used to produce realistic stereographs. As the objects we shot with this adapter were usually 15' away not the prescribed 25' most of the photos we took would be considered in hyper-stereo. The downside of hyperstereo is that the perspective of near objects is sometime too different for the brain to resolve easily into a 3-D image, so it may take a couple of trys to get the 2 images to merge.
Some other stereoscope resources:
Take a look at the "Build A Stereoscopic Viewer" article as well as the "Homemade Camera Stereo Adapter" article