Last night I finally put some paint on a canvas. Within 1 hour my black & 2 dark greys were sticky, touch dry after 2 hours. At this point I stopped painting and started swearing. This is very different to my usual experience of 7 - 10 days working time.
I'm doing some tests but hopefully someone can just say "It is xxx".
Canvas - bought pre stretched triple primed, brown ground applied as per Mark.
Stock paint - Windsor & Newton artist grade, with slow drying medium added per Mark. 15ml clove oil added to burnt umber per Mark. Blue, brown, white made last week. Red, yellow were made August.
Slow dry medium - made 21 May 2022 per Mark. Kept in screw cap wine bottle. Shaken thoroughly before mixing.
Palette paint - mixed Friday, transferred to 7.5ml snap cap pots & stored in fridge.
Brushes - previously dipped in brush dip, wrapped in cling film, stored in fridge. Saturday cleaned in odourless mineral spirits to remove sticky dip.
The dollops of stock paints on the glass palette are still wet after being stored in a cupboard overnight.