I actually use a slightly different method at the moment. I have a light tent (reasonably cheap on eBay or in Maplin Electronics) which is sat in front of a south facing window (although i do use a large lightbox whenever the natural light isn't enough). The tent i have is 36"x36" so its big enough to use for all sorts of subjects - various sizes are available though.

Yes, its a bit more expensive to set up than yours, but for those who don't want to build something, its always an alternative.

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