Having discovered that plum pine had so much potential for colour, I felt obliged to test for lightfastness and washfastness. This is my lightfastness testing apparatus on the day I set it up: it is a none too sophisticated set of threads wrapped around card, inside a heavy card envelope with a window cut out of it, which has been sitting in the front window since 23 June 2013.
At the top, 3 silk thread samples, handspun Wensleydale, handspun Polwarth, two shades dyed on BWM alpaca rich and finally, two shades dyed on Patonyle (superwash woool+nylon blend).
After over a month in the (winter) sun, fading is quite evident. I realise now that I could have made a lightfastness test which made the results clearer, but you’re stuck with my limitations on this learning curve. If you squint, you can see the original colour at the sides. The fibre that performed best was the handspun wensleydale with alum. It was also the winner on the washfastness test.
I have to say that I think I have chosen well in using the bulk of the yarn I dyed for some slippers (they are Fibertrends Clogs), which might spend their lives tucked under a bed and come out only at night! Here they are awaiting felting…
And here they are after a wash at 40C, with some commercially dyed companions.
Local & Bespoke 
Wonderful colours, too bad about the fading, although even the faded versions are pretty, in a slightly morbid Victorian way (grayish pinks always have that effect on me).
: )
Love those slippers!
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That slipper pattern is such a winner! I have knit dozens of them for happy recipients.
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Fab slippers and cloth!
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you know, there are a lot of commercial knitting yarns which are not light fast especially if left in sun from a window, so i don’t think it’s SO important. I once had a deep green wool suit from a famous London label (second hand purchase) – it caught the (winter in the UK) sun as it hung on my open rack, and was quite spoilt with a stripe down one arm ….
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It’s all true, and I’ve had that experience with clothing once in a while. It does depend a lot on what you intend to use the yarn for, whether lightfastness is a significant factor.
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