Spotlight effect?

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Hi there-- I am searching for a way to create a spotlight effect for closeup photography. I want to reproduce the upside down cone of light with the circle at the base showcasing the subject. I have tried a shaded 100watt bulb thru a 1/4" hole approx 12" above my subject. I had limited results(great subject lighting but no cone of light.) I used dryer lint to show the edges of the light coming down and that should work well. Flashlights are out because of uneven light. Any recommendations would be greatly appreciated.

-- Tammy Cowden (borgdad@phnx.uswest.net), June 17, 1999

Answers

A true spotlight is a point source focused through lenses. Theatrical lights (today) use xenon lamps for spotlights and tungsten halogen lamps with reflectors for ellipsoidal and fresnel lighting instruments. If you truly want a "spotlight" effect, you will have to use a lighting instrument designed to give that effect. The closest "cheap" alternative that I can think of is a low voltage tungsten-halogen work light, or a low voltage tungsten-halogen track light "spot" fixture. However, none of those light sources focus. There are some low voltage tungsten-halogen display lights available that do have a focus adjustment. The major attribute of the spotlight effect is the sharp edges which are made by the light being focused on a specific point. Spotlights, fresnels, and ellipsoidals all focus. Mole-Richardson makes an extremely small fresnel (about 6- inches long) that would work, but I would guess it is about a $300 light. Other than that, I'm out of cheap & easy suggestions.

-- steve (swines@egginc.com), June 17, 1999.

I've checked in my Calument Lighting Catalog and there is a Photogenic mini-fresnel listed for 124.95. Two different size snoots and barn doors are available as accessories. Depending on the size of your subject, the light with the small snoot may give you the effect you want.

-- steve (swines@egginc.com), June 21, 1999.

Thanks for the advice. My subject will be about 2"-3" high, most likely a goose egg. I have also been checking around and it was suggested that I could use a magnifying glass as a focusing agent and what about trying a loupe? I may need to purchase special lights for this in the long run but I am enjoying the challenge of finding a cheap alternative. This sure is turning out to be a great learning experience on light! Keep on looking!

Tammy

-- Tammy (borgdad@phnx.uswest.net), June 21, 1999.


I applaud your enthusiasm for finding an alternative. I usually don't have the time (as it truly is money made or lost) so I usually look for the least expensive (total = money + time) method. If you live in or near a large city, you may be able to rent the light you need from either a photo store, video / motion picture rental supply, or theatrical lighting supplier. The problem with theatrical lights is that they often have special plugs that are incompatible with regular wall sockets.

Making a snoot for any light is relatively easy using heavy-weight aluminum broiler foil. I always carry a roll or two in one of my lighting cases to make special flags, snoots etc. Wrapping the foil around a tube (I carry 18-inch lengths of PVC water pipe in 3/4-inch, 1-inch, 2-inch diameters - which I also store precut gels in). You wrap the foil around the tube then extract the tube from the foil, giving a pretty good approximation of a snoot. They ain't pretty but they're light weight and they work!

-- (swines@egginc.com), June 21, 1999.


Would I be correct in assuming that what you really want is a cone of light rather than a column of light? And would I do I also gather that to make the cone visible is as important as the lighted subject?

If so, let me take a stab at it. I don't think you need a special light source. First lets use a "hot" light rather than a strobe so that we can see what we are doing. Next, either select a very small source as compared to the egg (good luck) or make a larger light source smaller by using something to block the source down to a small opening. The small opening becomes your light source. Beware of light bouncing in from walls, furniture, your shirt, etc. Preferably this needs to be done in a closed room where you can control all of the light in the room. You now have a small light suspended above your subject. The light radiates from the opening in a cone shape to your subject. The size of the circle of light illuminating the subject can be adjusted by changing the distance of the blocking material with the hole to the larger (original) light source or by moving that combination closer or farther from the subject.

Now if I understand, you actually want two subjects. The obvious is the egg and the second is the light itself. To make the light visible you will need to position a dark background behind the cone of light opposite of camera position. Also the surface under the egg should be dark. You will never see the cone of light. But, you can see something in the light.....like dust, or CALUMET used to carry a spray can (about $15) of a product used to do exactly what you are attempting.

Another technique you might try is to use a small aperture and long shutter and use a white card to move into the cone of light for a brief period of time. Try a 10 second exposure using the white card for 2 or 3 seconds....sort of a "painting with light" technique. This is a technique used to trace laser beams for exposure on film. Try different time combinations.

Good Luck

-- Rick Stiles (rstiles@ghg.net), July 13, 1999.



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