Reddit reviews Tamron AF 90mm f/2.8 Di SP AF/MF 1:1 Macro Lens for Nikon Digital SLR Cameras

1. Your macro setup with the Olloclip 3-in-1 gives you 7/14/21x macro with respect to the sensor size of an iPhone 6s.
   
   
2. You purchased a Nikon APS-C dSLR. However, Nikon doesn't make a 70S. Did you mean D70S? The D70S is ancient and shitty by modern standards. Get a Nikon D3300 if you want to get a cheap camera with the greatest image quality per dollar. Otherwise, if you can sacrifice a little bit of image quality, get a used Nikon D7000, it's a better value camera overall in terms of non-image quality features.
   
   
3. You should buy the Tamron 90mm f/2.8 Macro or the Tokina 10mm f/2.8 Macro lens. Those are about as cheap as you can get for an actual macro lens. Any cheaper and you'll get into the territory where they slap a "macro" label on a shitty lens (like your 18-200 superzoom) and call it a day.

You could try reversing a 50mm with extension tubes which will give you a macro effect, although it won't be true 1:1 macro. (glass is different in macro lenses)
As others have stated a Tamron 90mm would be a decent alternative as it's a dedicated macro and pretty cheap.
Personally though, I'd spend the extra money and get the Nikon 105mm f/2.8G ED-IF AF-S VR Micro as it is incredibly sharp and fast and doubles as an amazing portrait lens. That is the macro one I use and also use it for weddings along with my 24-70mm.

By the way, your images and lighting look great. Nice colours and DoF.

Aside from /u/himekat's comment - most of the headphone shots were taken with my Tamron 90mm Macro. One of the best macro lenses and way cheaper than a Nikon one.

Tamron 90mm macro

$300 used all day long, you won't be disappointed.

The 50mm on the D700 is a good start, but the hard part will be finding a D700 for $1200-$1300. They're out there, they're just a bit hard to find.

As far as macro, the $500 Tamron 90mm macro is a well-recommended, affordable option. Keep it mind that it's f/2.8 from 10 feet to infinity, and f/5.6 at 1:1.

Alternatively, if you want really cheap, you could use macro reversal rings, but nothing beats a real macro lens.

I've been getting good results with a Tamron f/2.8 90mm on a D3100.
It's around $400. Tamron SP AF 90mm f/2.8 Di

I've since added a speedlight which does wonders when shooting fast moving fish in low light.

Is the macro lens this?

The difference between a prime lens and a zoom can be quite staggering. I use a Tamron 90mm prime lens for macro work and it's tone and bokeh are stunning. It's even half the price of the equivalent nikkor lens (the 105mm micro from nikon).