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RE: Tesla Coil Photography

Hi Terry:

I think your problems are:
1)	The handheld camera is too unsteady and causes blurring.  A tripod
is a must.
2)	Film speed is too slow and/or aperture is too small.  I use 200
speed film at /f 2.8.  400 speed should be fine too, perhaps better as you
can use a smaller aperture and get a better depth of field.  I've never
tried 1000 speed.  You may get great depth of field, but it will probably be
very grainy.  Never use automatic exposure.
3)	Ambient light washes out the sparks, and unbalanced
(florescent/incandescent) lights lend a yucky tint.  I think photos should
have enough light to show the coil itself, not just sparks coming from
blackness.  Light from the spark gap, particularly if taken indoors with
reflective walls and ceilings, should provide ample, balanced, ambient
light.
4)	I also use a Minolta X700, on "B", with a shutter release cable.
Exposure times are not at all critical unless ambient light levels are high,
in which case everything will be overexposed.  The spark gap will always be
overexposed, that's a given.  You should NOT use UV or other filters as they
may cause reflections within the lens and you'll see ghost images of the
spark gap.  Mostly the difference in exposure times will affect the number
of arcs seen in the photo - a Medusa head for long exposures, or 1-2
streamers for shorter exposures.

Regards, Gary Lau
Waltham, MA USA

		-----Original Message-----
		From:	Tesla List [mailto:tesla-at-pupman-dot-com]
		Sent:	Wednesday, July 28, 1999 8:01 PM
		To:	tesla-at-pupman-dot-com
		Subject:	Tesla Coil Photography

		Original Poster: Terry Fritz <twftesla-at-uswest-dot-net>

		Hi All,

		My pictures of streamers did not turn out well and I could
use a little
		advise...

		I posted my "best" picture ( the one the shop bothered to
print) at:

		http://www.peakpeak-dot-com/~terryf/tesla/misc/phototry.jpg

		This was hand held, florescent lights without the florescent
filter, ASA
		100 film, 3.5 aperture, the camera was controlling the
exposure (thank
		goodness, or it may have turned out bad :-))....


		First let me tell you what I have...

		Minolta X-700 manual camera that seems to like working
around TCs.
		Has auto exposure and aperture priority which is probably
not of any use
		for TC work...
		Minolta 35-70 Macro lens with speeds of 3.5-22.
		Minolta 1:1.4 lens with speeds from 1.4 to 16.
		Kodak Royal Gold 400 and 1000 speed film.
		Tripods, popular filteres, and flex shutter cable.

		So.... I should be set, but...  I am NOT the worlds greatest
photo guy.  I
		have read the books and even take "Popular Photography" but
I am just not a
		"natural" at such things...  I get all the technical stuff
and I have a
		good understanding of what all the setting do but the "skill
and
		experience" factor is a definite problem...

		For the last set of attempted pictures, I used 100 speed
film with the 3.5
		aperture.  The exposure was about 5 seconds using the "one
Mississippi, two
		Mississippi" timing method with the camera hand held and
working the variac
		with the other hand...  I will use the tripod and flex
shutter cable next
		time...  One problem was that the film and lens speed (100,
3.5) were not
		great enough for an arc to burn an image on the film with
the available RMS
		light from the arc.  Thus, I figure, faster film and perhaps
the 1.4 lens
		are needed (I have been reading the archives on this).  If
there is enough
		ambient light for the camera electronics to do the exposure,
it does a good
		job light wise but the streamers seems dim (with 100 speed
film) thus I
		guess the 400 speed would be much better (I have 1000 too).

		Sooo...  I have the "stuff" and know "some" things but I was
just wondering
		if anyone had any suggestion as to the film, aperture,
time... (especially
		the time!!) settings to get me into the ballpark for a sort
of dark room.
		I realize that there are variables and I'll have to try
things, but I seem
		pretty darn far away at the moment...  The room is usually
pretty dark but
		I can make out the coil and other objects ok so it is not
pitch black...

		Any advice is welcome.  I hate to go through a bunch of
sessions and film
		just to START getting reasonable pictures...

		Thanks,

			Terry