Dyeing outdoors

With all the sunshine we've been having (wow it's summer!) there has been discussion on the CQ list of indigo vats and other dyeing. I don't know what the scientific effect of leaving the dyebath in hot sunshine is, but it seems like an incentive to do something usefully messy, and I'd like some more black(ish) and sludgy colours - and to finally use some of the white cotton sheets and tablecloths that have been accumulating -I dug out the dye bucket, removed some hardened clay (remnant of sculpture course), and set out to follow this method: "I dyed around a metre of fairly thick pre-washed cotton by dissolving 3 tablespoons of soda ash in a litre of water, then I added a litre of salt solution (that's a litre of hot water with 250 grammes cheap salt). I mixed 3 teaspoons of black Procion with an eighth of Scarlet and an eighth of Golden Yellow and dissolved it in some fairly hand hot water, making it up to a litre once the powder was all dissolved. Once all these were combined in the bucket I added the dry fabric and moved it around every 5 mins or so for half and hour; then I left it out in the sun to cook. It was out there for four hours."

While gathering supplies and materials, I discovered a packet of Dylon black (recommended for getting a true black!) and an unopened jar of discharge paste that must be several years old by now -First hitch to the plans: the clouds had moved in. Second hitch: although I've been collecting old tablecloths etc with the express purpose of dyeing them, it's surprisingly hard to cut them up! Deep breath, and - ! Some crunching and a few elastic bands later, and we're ready - dye is mixed and bucket is sitting on the windowsill to await heating by the occasional sunshine -
While I sat at the computer and did some paid work, the dye (sun or no sun) sat and did its own work.

Every fabric reacts differently... and they always look most gorgeous when they're wet. It was late evening by the time I took the fabric out and rinsed it off (washing with a bit of metapex/synthrapol) -But this morning, when they'd dried, the story was more "shades of grey" than "black and blue" -
These were white cottons dating back to the 60s, and two bits of beigey linen. Perhaps they will become areas of cloud -