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Re: coil photography

Original poster: "Dave" <dgoodfellow@xxxxxxxxxxxxxx>
I get good results by using a digital camera that can do long term exposures. Also best if you have an adjustable ASA (iso) I set my camera for ASA 400, and open the shutter for 4, 8, or 16 seconds. Sometimes the 16 second shots will be too bright in the final rendering of the photo, so I take a black piece of paper, hold it in front of the lense, and during the 16 second exposure, I look for particularly long sparks. When I see them, I snap the paper to the side of the lense, then rapidly return it in front of the lense again. I may do this 4 to 6 times in the 16 seconds. The result is that you get a number of short presentations of the sparks to the camera. This also helps reduce the "banjo"effect from rising rarcs captured in a long exposure. Another trick I use is to have a flashlight with not so great batteries in it, to light up the coil. I set the self timer on the camera, with camera mounted on a tripod, and as I see the camera shutter open, I light the flashlight, and sweep from the top of the coil to the bottom, in a half second or so. Then I turn the flashlight off, and hit the coil button a few times, before the shutter closes. This gives a nicely lit image of the coil, keeps the room dark, and still shows off the sparks nicely. 

Good luck!
Dave Goodfellow


----- Original Message ----- From: "Tesla list" <tesla@xxxxxxxxxx>
To: <tesla@xxxxxxxxxx>
Sent: Thursday, April 19, 2007 10:23 PM
Subject: Re: coil photography



Original poster: ianhelixsp@xxxxxxx
Hi,
Some of the best results I've achieved have been by using a low wattage bulb (100watts) illuminate the coil itself which also helps the camera to focus (assuming it's AF) set the camera to program mode, the highest ISO setting available and set the exposure compensation to -2. The latter tends to stop excessive shutter times. The subject material i.e. the streamers are very small in area relative to the whole scene, budget cameras tend to meter the light as an average for the whole scene, so if you try for neautral or + exposure compensation the picture will end up very grainy with lots of pixel noise. 

Hope this helps, Ian

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-----Original Message-----
From: tesla@xxxxxxxxxx
To: tesla@xxxxxxxxxx
Sent: Thu, 19 Apr 2007 2.29AM
Subject: coil photography

Original poster: "Scott Bogard" <teslas-intern@xxxxxxxxxxx>

Greetings all,
I am having trouble getting good pictures of my Tesla coil in operation. It seems the cameras I have available, do not have a very adjustable exposure time (and I don't have any clue how to take a double exposure, without using conventional film, which is useless to me as I don't have a scanner, so I cannot put my pictures on the computer). I can get "decent" videos, but still shots captured from them generally only show the arcs, and not the coil (which gives no perspective of actual size), plus the DPI is too low for my taste anyway. Any suggestions would be appreciated (even referrals to the archives would be great, if you could give me a general place to look, they are vast, and I am pressed for time!) Thanks a heap. 
Scott Bogard.

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