If you want something good for about 400 bucks the best I can think of is the camera I ahve now that I spent about 2000 on about 8 years ago is about 400 bucks art office depot now. Its a canon dslr 8.1 mega pixels. Unless your shooting to output/print posters you dont need anything over 8 mega pixels. I know my stuff, and have been told I take excellent pics so look through my shots if you want the proof.

1. a dslr so you can change the lenses
you want a macro lens 60 mm f 2.8
and a regular lens which says 24-85 or 18-118 depends.

what you really need is any camera that will hold a tripod
and you can change the shutter speed and f stop
the F-stops are the hole in the lens that lets the light in. The number is just the bottom (ok, the denominator) of a fraction.
Shutter speeds control how long the lens lets the light in. The number is just the bottom (ok, the denominator) of a fraction.
as long as your camera has that theres no problem with what you get.

I got a canon and have used a canon for many years
the controversy between nikon and canon was years ago and it was basically that nikon was better because they were universal with the lenses and other applications. while canon used specific motors in there lenses and were only compatible with other canons.
hope this helps anything else hit me up id love to help even though im not on this site to much anymore. remember any camera will do as long as it had a timer, fstop and shutter speed.

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"All things are subject to interpretation whichever interpretation prevails at a given time is a function of power and not truth. "
Friedrich Nietzsche