I made one before I saw the plans but it came out pretty close in concept.
I just used a big piece of plywood 2'x4' as the base and added 4 upright 2x4s in the corners and then connected them with other 2x4's at the top to stabilize it.

I had to make it tall since I have some 3' trophies and 18" plaques. The top can be covered or left open for the real tall stuff.

I used big 3' wide strips of thin white foam we have for packing for the light diffuser but I use the bed sheets for part of it now since I saw the plans.

Our asi dept. also bought a nice systems at the camera store for smaller stuff.

It folds up flat like a briefcase for storage and unfolds into about a 2' cube with a white backdrop and light diffuser sides. It even came with 2 lamps and a tall and short camera tripod all for around $100. One thing this doesn't have is a front with a whole to shoot the picture through. This is only a problem if you are doing highly reflective things like crystal or silver trays.

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