Equipment for extreme macro

You'll hear a lot about people using "microscope objectives" at magnification from 2x up to around 40x.

• They’re surprisingly affordable.
• They taper down to a relatively small end, making it easier to move lights in around your subject.
• Some have simply amazing optical quality.

Microscope objectives come in two main flavors: "fixed tube length" and "infinity". A fixed tube length objective focuses on your subject and projects a focused image directly on your camera's sensor. That's the kind you use with a bellows.

An infinity objective focuses on your subject and projects an image that focuses at infinity. A second lens farther up the microscope tube takes that image at infinity and focuses it on an eyepiece or camera sensor. The most popular tube length spec is 200mm. Hey, guess what! Your 180mm lens is a great "tube lens". It's good at grabbing images at infinity and focusing them on your sensor. That's exactly what we did with the reversed 60mm and the macro coupling ring: we built an infinity microscope: the 60mm "front lens" is our microscope objective, and the 180mm "rear lens" is the tube lens.

Or, you could look at Olympus objectives. They deviate from the industry conventions and use a 180mm tube lenses, so your objective will perform as marked.

So a fairly simple adapter that looks like a lens cap with a hole threaded in one of the standard objective threads gets you going. Make sure you get the right adapter for your objective. Now, remember I said the industry standard for tube lenses is 200mm? Your 180mm will work just one, but the magnification will be 10% less (180mm/200mm) than whatever is printed on the objective.

A "starter" objective could be a Nikon 4x "plan", the "black" objective, which goes for around $120 new. The adapter to stick it on your 180 is about $20. It has a working distance of around 30mm.

A step up is a 5x "plan APO" about $200 used if you keep an eye on the bay of e.

The Mitutoyo 5x plan APO is a long working distance objective that's extremely good, but around $700 new and almost unheard of on the used market. They get snatched up fast.