We are hoping to fly to Antalya from Manchester in February but have a 1 hour stop over to change planes in Istanbul
Depending on the queues at immigration when you land at international, one hour is quite tight - be prepared to put a jog on when you land! It's only a 5min walk, once you get land side, to domestic but you've then also got the queues at security to get back airside.
Fortunately, you're travelling THY so a) they'll be aware of transit passengers for your domestic leg and often hold it back when the international flight is delayed and b) if you do miss it, they'll put you on the next available flight at no charge (or put you up overnight if the last flight already left).
Here's a handy wee map of
Ataturk Airport.
JF