Not a daft question and hopefully a Duratec owner will comment. Meantime..... If I check my Sigma engine when hot after 30 secs from switch off the oil level reads low. However after a blat, by the time I switch off, climb out, realign my ageing spine, have a pee, remove the bonnet etc. etc. my hot oil reading tends to be OK. Between switch off and getting to the dipstick the process probably takes me at least 5 mins. I have a preference to check my oil before I start up and set off. After an oil and filter change, with a short start up and cool down you can mark your dipstick to indicate your cold oil level. I remain surprised how much the full dipstick readings on my car vary between hot and cold.