Each have different photography styles, preferences and ways of doing things. Off the top of my head, I can think of about 5 different "speciality" tools for depending what you like....(1) PC socket for studio work on older cameras (2) Tilt Shift lens for architecture (3) Macro lens for, well....small things (4) 5-in-1 reflector for outdoor work (5) Tripod for long exposure shots (none of these being exclusively limited to what I've said eg the Nikkor 55mm Macro Lens also doubles up as a pretty neat portraiture lens, and from my personal lens selection provides some of the sharpest images).
I'm of the personal opinion that sometimes individuals will bash that you MUST have Tool X in order to shoot Subject X. Rubbish I say. There's nothing wrong with your kit lens. There's nothing wrong with having a R250 (about US$15 if I convert my money) 2nd hand tripod as opposed to a R6000 (about US$400 if I convert direct) Manfrotto tripod. They do the same job. Well kind of anyway.....Let me say more!
The 50mm lens. A topic of hot debate. Considered a MUST HAVE by many salesmen across the world. Ever wondered why? Extra sales. Sure, its a great lens. Its sharp. It keeps you at an okayish distance from a model that you don't know. Its a practical go-to. But did you know our natural line of vision would actually be a 42mm lens?
An 18-24mm is the "landscape lens". Ever ask why? Sure, it grabs in stuff from a SUPER wide angle. Try it on straight lines like a building, and you're gonna get a weird looking building. Its a very limiting lens. My solution - Nikkor provides an 18-55mm kit lens. Zoom out all the way to 18mm. And it keeps straight lines straight. Ish.
Anyway, here's some of the items I keep in my bag for photoshoots:
- 1 x Nikon D7200
- 1 x Nikon FM
- 1 x Olympus Trip 35 (an 'emergency' film camera for if ever my FM decides to give any issues. Do your own research as to whether its something you'd use or not, despite it being a point-and-shoot).
1 x 50mm AI Nikkor lens
1 x 35-200mm AI Nikkor lens
and last but not least
1 x Rolleicord V which isn't always used, but can come in useful if I want to make special, large prints.
5-6 rolls of 35mm film (the type varies on what I'll be shooting)
2-3 rolls of 120 film