alternatives for silver/black fabric?

[Mike Wilde]

I'm working up a large do it on the cheap DIY soft box for doing soft light for a planned nude series . The model will be streched out on the floor, and shot mostly with the soft box slightly above the model and directed as backlight.

The prototype mock up to date has a 36x80 inch mylar translucent drafting film front, stapled to a white painted cedar frame. The grids to reduce the spill from this monster are made up from interlaced corrugated cardboard painted matte black, like beer case dividers. They are assembled to form 6" squares, 6" deep. The rear sides for the box to date are white foam core panels angled in towards the light sources. The light sources are mounted on individual light stands.

The lighting effect when firing two 500w tunsten photo floods is nice and even, but a lot of the light is being wasted bouncing out the back.

The mock of the actual model, with me, a balding hairy limbed middle aged photographer, standing in for the model squezzing a remote bulb is so far the least attractive part of the test photographs.

The longer term solution I believe is to feed at least a pair of Metz 60/45 series heads, or even bite the bullet and buy propoer studio flash. Going with flash will allow the rear enclosure to be essentially closed up, since the heat build up will not be as much of an issue as when using tungsten. I was going to put a couple of 26w or 42w 5000K compact flourescent units inside as modelling lights, as the studio is otherwise dark when I use this set up.

I would like to remake this to be portable in the future, to take to shoots. I can see how to make the front and frame with steel/fibregalss rods (recycled tent poles)and pvc pipes with velcro to attach the face. The grids fold down flat.

The foam core rear does not pack up well at all however.

Can anyone come up with a more portable for the backing incarnation, that would give the effect of the standard silver/black fabric without the going rate cost? I see that if I go the traditional photo retailer route that I am up for about $200 in fabric. I have treid the aluminzed emergency blankets type mylar sheets, but have found they actually let a lot of light through.

Thoughts?

 

[Mike Wilde]

Solution to DIY Softbox created

The last post asked about silver/black fabric for a . I finally clued in that I did not need the back side black if the reflector was 100% light proof.

So aluminum foil (shiny side) made the reflector. The reverse (dull) side of the foil was spray glued with Scotch Super 77 adhesive, and attached to more of the surplus mylar that I had fabricated the face of the soft box from.

The resulting sturdy sandwich was stapled to a wooden frame made up from surplus knot free lumber that I salvaged and stored in the garage attic some years ago, to make the reflective surface. The wood was ripped to 1" by 1.5" section, and each 'wall' has its own frame to allow it to be assembled with a few screws, and the result seems the right mix of sturdiness versus light weight for something with a wooden frame.

It is not as light or portable as a commercial softbox. I estimate that it weighs about 15lbs. But it is 6.5' by 3', and 3' deep, a big box.

However it was made for the cash outlay of one can of spray glue, and a roll of foil to replace all the aluminum foil after I exhausted the kitchen on hand supply.

No real photos of what it gives for soft lighting yet. I was calibrating its light uniformity with a dgithing from the office, as it is cheaper to use than polaroid.

I was lighting it with a Metz 60 CT-1, with the frontal diffuser on the flash. It yielded F8 at 6' from the face of the softbox, with light falling off by half a stop at the long ends of the box, since there was but one source location within the large reflective cavity.

The next step is to gather up a round of 3-4 Vivitar 283 like flashes, and permanently array them inside along the back to get the uniformity up. These flash units will likely come from a camera show. or more likely summer garage sales.

I have previously experimented with gang feeding power to multiple flashes that are usually powered by 4 AA batteries, using instead the 5V output from a surplus desktop PC power module. It is rated to deliver 5V at up to 20A. The result is that it recycles the flash units in under 5 seconds, even when all are set to full manual output.

Some day I may have the cash on hand to buy proper studio flash, and all the 'factory' modifiers that go with them. Until that future time I will continue to be the mad hatter DIY inventor, and the saved cash flow will instead continue to fund more pedestrian adventures, like paying the mortgage, getting new glasses for the kids, keeping them enrolled in swimming, and all the other minutae that funding a household entails.

 

[MattKing]

Mike:

Sounds like a good project result.

One warning about the the flashes using the 5V power supply - watch the heat!!

Most flashes produce a lot of heat when they are cycled frequently at full power. I've seen portable flash heads where the heat produced has actually melted the plastic housing.

Matt