Was this coloured fabric?
I've been experimenting using blues, including using the computer, and it seems incredibly hard to get the difference in brilliance right when adding colour to the picture. But I think it might work in browns - it would be easier to tea dye light fabric to get shades of brown than to buy shades of grey, I think.
Hanne in London
Please excuse me for replying to myself!
I've tried, I really have. I have to mock-ups with bits of fabric stuck onto paper, I have several prints from a graphics program with various colour ways.
I'm not sure this illusion works in anything but grey tones!!! Not even browns, I tried on the computer thinking that I could use tea dyeing to get flat, brown shades to mimmick the grey ones.
I'm waiting for the colleague who knows about illusions to come back from lunch.
If it really only works on grey, I'm not going to be making anything on this right now, and when (if) I do it would have to have sheers, pens, crayons and all kinds of other stuff on it to keep my interest. It seems that part of the reason for this trick working is the image being flat, and I just don't feel like deliberately making a flat quilt (flat as is hang/lay flat: yes, but not in terms of colour/life).
Arrghhh!
Hanne in London PS - no digi cam and currently no scans either.
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