We went on a 9-day trip to Istanbul, and it was great. The only fly in the ointment was the shiny new Istanbul International Airport (IST). That is the most aircraft photography unfriendly airport I've been to. Admittedly, I haven't been to all that many airports, but still.
Firstly, if you don't drive (and you really shouldn't drive in Istanbul unless you have a death wish), your only option is the official Spotter Area. In theory, it's accessible every Saturday from 15:00 till 18:00.
Theory, meet reality. To be admitted, you have to register, but the registration page is often outdated, or it doesn't show any registration form at all. If you are lucky, and the registration form for a random Saturday magically appears, you need more luck still, because the number of places is limited to a seemingly arbitrary number. One time I checked it, the number was 100, the next time it was 50. As soon as the number is reached, the registration form disappears.
As I'm writing this, the page shows the following:
The iGA Istanbul Airport Spotter Area will be opened on Saturday, August 10. You can apply for free on this page from August 5 to August 7 to visit on Saturday, August 10. Applications are limited to 55 people. Those whose names are not on the list will not be allowed.
Today is August 7, and the registration form was not available between the given dates. Also, the text says 55 people, but further down the page, the number is 50. In short, the whole thing is pretty much useless.
I contacted IST customer service twice, asking if and when the registration for the Saturday that worked for me would be opened, but my emails went unanswered.
The clever person that you are, you might think, Alright, if I can't get access to the Spotter Area, I might find a place in the airport itself to photograph aircraft on the apron, even if I have to do it through the glass. I'm sorry to inform you that whoever designed the airport had outsmarted you. There are very few places in the airport (at least after the security check) where you can actually get close to the glass panels. But the spots where you can do that are pretty terrible. Plus, the security in IST is pretty tight, and anecdotal evidence suggests that you shouldn't flaunt your camera.
So yeah, thumbs-up for setting up a dedicated area for aircraft photography, but serious thumbs-down for making it virtually impossible to access thanks to a convoluted, utterly impractical, and ultimately broken process. What a disappointment!