| Brittany Spencer | Blake Bommelje |
| Materials | Diagrams | Description of Equipment Setup | Description of Triggering, Timing, and Imaging Methods | Description of Experimental Setup |
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Materials:
Diagrams
Description of Equipment Setup: The test tubes are filled with a small amount of potassium-chlorate, which is then put into its stand under the hood and heated until the potassium-chlorate is a liquid (see side view). The Gummibear is then dropped into the liquid potassium-chlorate to create an explosion and intense light. The trigger is placed very close to the test tube so that it will be hit by the light as soon as it the experiment starts to react, but not too close to be burnt by the Bunsen burner. The camera is attached to the trigger via a series of cords (see Cord Setup below), described (via colors used in our project) as: We connected the yellow end to the tip of the RCA-like plug. We were careful not to go past the black line on the RCA Plug. The red cable connects to the base of the RCA-like plug. Then on the three-banana-clip end of the camera cord, black cable connects to both the black and the blue banana clips. The red one joins onto the connection shared by the black and blue clips, and the yellow one attaches to the remaining yellow banana clip. The end of the cord that is remaining (it should be specifically for your camera – ours was a connector made for the Nikon D1) plugs into the camera. The entire setup looks something like this:
The Camera is on a tripod, and when the light triggers the circuit, the camera goes off (meaning the shutter opens and closes) and the picture is taken.
Description of Triggering, Timing, and Imaging Methods. We used a light source, and therefore a light trigger, because our experiment gave off light on its own and this made the flash unnecessary. Our trigger is a circuit which incorporates both a timing mechanism and a photo sensitive trigger. The trigger includes both a sensitivity (which we kept at maximum) and a delay (which we had at short and semi-short durations, depending on the photograph that we wanted.) Timing wasn’t a real issue except in the last two shots where we tried to do things by hand. We attempted to drop a gummibear into the test tube and time when we opened and closed the shutter ourselves instead of letting the light trigger do it. That was not very effective and thus it is good that we were using a trigger for the majority of our pictures. Our imaging methods are to set the camera on fine resolution with an ISO of 800 and change f-stops as necessary, depending on the amount of ambient lighting, proximity to the exploding GummiBear, and how much detail. If we wanted a great explosion, we’d use a larger f-stop. If we wanted to try to see some detail in the explosion (such as hot and not-so-hot spots) we used a smaller f-stop, making the hotter spots show up brighter since they gave off more intense light. The other part of timing was making sure that the circuit was reset after each photograph, otherwise the trigger would not go off again and we would be unable to release the shutter manually. This was not especially difficult, since resetting up the project took several minutes. Below are the circuit diagrams for the circuits we used in this setup.
Description of Experimental Method We performed at tried-and-true experiment (at least, by NCSSM standards), affectionately known as "The GummiBear experiment" in which potassium-chlorate and sucrose create an explosion with lots of light. Photographing this did not take extreme skill, just lots of time. We had to construct a working trigger and delay circuit to capture the event and set off the camera, because human error would have been too great a possibility in this case. However, our basic experiment consisted of:
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