Apr 11, 2005


(stolen over several generations from lighting master Bill Holshevnikof)

This assumes you're using an open-face light with barndoors on it, and want to convert it to a bigger, softer source for tabletop or portrait type work.

You need: foamcore sheet, Xacto or sharp carpet knife, gaffer tape. Sheet of tough spun or similar. Bulldog type paper clips. Extra credit: use 2-piece Velcro tape instead of gaffer's...

Begin by plugging the light in and placing it on it's side on the concrete studio floor, barndoors open. Turn it on, and if there is a wide/narrow adjustment, flood that out maximum width. You should now have a shiny cone projecting along the floor. Trace this with a crayon or similar...actually, just marking the angle & width at the near end.

This is the KEY step: your actual box must have a slightly WIDER angle than the cone of light emanating from the unit. This above all else is why the foam-core stays cool, instead of turning to stinky slag. The greatest portion of the light is not touching the core material, but only impinging on the diffusion material at the open face. So, to tell it a third way, if the cone of light has an angle of, say 45 degrees, the trapezoidal sides of the box must have an angle of at least 50 degrees. Don't crowd the light! We do this step twice; once to measure the sides, once to measure the top & bottom. You end up with two pairs of matching trapezoidal shapes, one set (Top & Bottom) wider than the other, in aspect ratio. When you want to light a vertical, turn it, and reattach.

Assemble the box with white gaffer tape on the corners, inside and out. Do the inside edges first, dummy:-) The small end of the box will attach to the barndoors with tape or clips. Personally, I taped bulldog clips to the foamcore, so I can pop the whole thing off and use the light the other way if needed. Also, using the clips like this, and slitting one joint with a razor blade, lets you fold the whole schmeer down flat for storage or transport. Or if you're Bill, you pitch it when done, since you can make a new one on the spot in minutes.:-) (Also, make sure there is an air gap at the narrow end of at least an inch. When you put the diffusion over the front, (use push pins) a little gap on the sides helps too.)
Check these lightboxes out too.