One other tip - when flying out of Egypt arrive at HRG airport at least 4hours before your flight - and expect to have to go through security again in CAI - and expect that to be some of the most thorough security you have ever been through - multiple multiple checks to pass through.
I would NEVER go through Cairo airport with camera or dive equipment again. If I am going diving in red sea, I'd fly direct to the closest airport to my diving destination.
Cairo airport has some of the most corrupt people on earth. The will make your life miserable and shake you down every step of the way.