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Using Powerpoint Digital Imaging Files & Forms in Adobe Acrobat Classroom technology manuals Pinhole Photography Astronomy

Positive preview with video return to Pinhole Photography Many people have trouble visualizing a positive image from looking at a negative. In a pinhole photography workshop this can lead to discarding a promising image or struggling to get a print out of a bad negative, rather than going out to experiment with a better image. Getting an instant positive preview is also just nice instant gratification. I've used television cameras to display a positive, and rather enlarged, image of a paper pinhole negative. A negative image "special effect" is common on many Hi-8mm camcorders and almost universal on mini-DV camcorders. (The first camera I used was a black and white camera from the 60's with a "reverse" switch on the back.) These cameras also usually have sufficient close up capability to fill the frame with a 4 x 5 and probably smaller negatives. Inexpensive diopters are also usually available to get even closer Many of these smaller camcorders include a small LCD panel to view the image, but almost all also include composite video out that can be routed to a monitor with a video input. Some also include RF output on Channel 3 and 4 like regular VCR's if you only have a TV receiver with a cable or antenna input.You could also connect the camera to the video inputs of a VCR and connect that to the TV over the antenna/cable input. Displayed on a standard 27" classroom television, this makes for a rather impressive although fleeting, enlargement. It can take some adjustment to avoid getting glare from a wet, glossy paper negative, but placing the camera between banks of fluorescent overhead lights, rather than directly under them will do the trick. A copy stand would be the ultimate support. I have used Hi-8 and Mini-DV cameras that also allow exposure adjustment, simulating variations in print exposures. Ancient black and white TVs used to have a Brightness knob that could do this, and I suppose the Brightness adjustment on new TV's controlled by the menu could work, but I haven't tried that, and you'd want to make sure it was reset to normal brightness when you were done so you didn't irritate your local media specialist. Some camcorders will not stay in the camera mode for more that five minutes without recording in order to protect the tape heads from excessive wear. When the camera drops out of the recording mode, it can take a few adjustments not readily apparent to an unfamiliar user to get it back into the "negative" mode. The solution is just to put in the longest tape available and put it on record. That can give you at least 2 hours before the camera has to be reset (and coincidently provides an audio record of participants reactions to their photographs). Some camcorders will stay in the camera mode indefinitely if there is no tape loaded. When I do this this younger audiences, at least a few minutes get used with a kid under the camera and the rest laughing at the negative image, but the novelty of that wears off and they're excited to see the instant positive version of their negative.