Thanks @MavisMcMinty and @CinnamonCoffee . I don't tend to use moisturiser without spf in the morning. I use serum, then spf moisturiser, usually about a F50 using the amount you suggest. Are you saying I need a moisturiser, then a separate sunscreen? I'm not saying I wouldn't if I thought it would stop damage, but I leave time between stuff, to let it soak in and minimise the risk of pilling, and suspect that I would either never get out of the house in the morning, or would need to leave the serum to just the evening routine.