[Radio Wrangler]

You can get mounting rings for lenses that join two lenses together by the filter mounting threads on their 'input' ends. SRB Griturn were a supplier I remember.

As Emeritus says, you couple a pair of, say, 50mm lenses together this way and get a superb macro setup. Only one lens has to fit your camera, the other can be for any system just so long as the filter thread diameter suits your adaptor ring.

Another macro approach is that extension tubes and bellows were made to move lenses away from camera bodies. Posh versions included bellows with guide rails and rack and pinion focusing. If you use Nikon F or Pentax K mount cameras there are all sorts of macro systems along with stands for copy work and macro work which can handle microfiche.

These things can be expensive from dealers who see them as collector's items, but they turn up in junk sales for next to nothing if you know what they are and keep your eyes open.

'Digital' cameras that aren't recent models go for a tiny fraction of their original prices, and can still be useful, and get you into a system which includes fancy macro accessories.

David