While macro photography can be fun and fascinating, it does require at least a little specialized equipment. Dedicated macro lenses tend to be quite expensive, and while they remain the best way to tackle the genre, there are other options. But first, let’s see why they’re usually the best option.
Full range of focus. Macro lenses can usually focus from 15cm, give or take, to infinity – the range varies a lot, because some are optimized for very close work, others for working distance from shy subjects. But all of them can be focused to infinity and thus used for other subjects as well.
Sharpness. As a rule that has few exceptions, macro lenses are usually the sharpest out of any manufacturer’s lineup, partially because the end results are often cropped and enlarged significantly because the photographer is after the detail. On top of that, the lenses are almost always optimized for a flat field, for copy work – this means they will produce the same focus and sharpness across the frame, for subjects that remain parallel to the sensor/image plane, as in, copying a photograph or printed page. This makes little difference for most other macro subjects like insects or flowers, etc., because their distance to the lens/sensor plane isn’t constant.
Bokeh. Since macro involves high magnification, depth-of-field drops off significantly, meaning the background is very often out of focus, but we still want this to be smooth and undistracting. Most macro lenses have a larger number of aperture blades to help smooth out these defocused portions – some much better than others.
Focus limiters. Many/most macro lenses have a switch to limit the range of autofocus, since we really don’t want the focus racking all the way out to infinity and back when it fails to lock onto the bug in front of us. This can be handy, but less use than initially supposed, since often enough, we may switch to manual focus anyway.
1:1 magnification (or better.) This is often considered the real definition of a macro lens, meaning that the image it produces on the sensor plane is the same size as the subject itself. While there are exceedingly few circumstances when this is necessary, it’s a guideline towards knowing what the lens is capable of.
Don’t be fooled by the countless variations of lenses that are billed as “zoom macros” and so on – “macro” is a popular term and manufacturers prey on buyers that are triggered by it. Basic guideline: if it actually has a variable focal length, a ‘zoom’ lens, it probably doesn’t allow very close focus or high magnification, and it certainly isn’t optimized with most of the factors above. Generally, if you look closely at the lens specifications you’ll find what its actual magnification is, and if it’s listed as anything less than “1:2” (such as 1:3, 1:4,) forget about it. Do not confuse this with the aperture specs, often listed on the front ring of the lens as “1:3.5” or “1:5.6” – this has nothing to do with magnification and only refers to maximum apertures of f3.5 or f5.6. Most macro lenses are f2.8 to f4 maximum – the lower the number, the better (more light to focus by) but it often isn’t a very crucial factor, because to increase depth-of-field and how much of a small subject will still be sharp, we’ll be shooting frequently at smaller apertures anyway, f11 to f22 or further.
So when we go to these other options for macro work, we’ll often do without at least one of the above factors, possibly most of them – it’s up to you to decided what you can live with and what you can’t
Close-up diopters (“filters”). “Filters” is an incorrect term, but a lot of people still use it because these screw onto the end of an existing lens like filters do. However, they don’t filter out light, because they’re actually lenses themselves, and come in different strengths. As macro options go, these are always the cheapest and easiest to implement, just adding them to one of our existing lenses, but the results are often sub-optimal. Most especially, the sharpness is highest right in the center of the image and drops off significantly, even resulting in distortion at the edges – not at all an option for copy work. They’re okay in a pinch, and certainly inexpensive, but they’ll typically be forgotten and unused as soon as any other options are available. They also have to be specific to the lens threads, so harder to implement for multiple lenses
Extension tubes. Such a simple idea – all these do is go between the camera and lens to move an existing lens further from the camera/sensor plane so the image it throws is larger, just like moving a projector further from the screen. Their sharpness depends entirely on the lens used, which is hard to predict – some lenses do great with extension tubes, others are too optimized for their distance. Extension tubes often come in sets of three different lengths and can even be used in combination, and are fairly inexpensive – more so if you go with ones not from the original equipment manufacturers, which is fine because they’re empty tubes that only have to pass the info back and forth through the lens contacts. There are two distinct downsides: the first is that there is notable light loss from moving lenses further away, more so with greater distance (more extension,) and this can defeat autofocus as well as making subjects harder to manually focus upon. The second is that lenses are optimized for that distance to the film plane, and increasing this can introduce more distortion and chromatic aberration (color fringing.) It also eliminates infinity focusing – the more extension, the less you can focus on distant objects. However, they’re a useful thing to carry in the bag and can work great in a pinch, or if the dedicated macro lens isn’t handy.
Macro bellows. Largely the same as above, but a continually variable level of extension that can far exceed most tube sets. The loss of light becomes even greater, as does distortion and aberration, so this typically works well only with a few lenses, and experimentation is in order. This is also a heavier and bulkier rig and works best with tripod work, which limits the field uses – not impossible, but flexibility is not the keyword here. Focus is usually achieved with the adjustment of the bellows extension, and aperture is adjusted manually – this is why older manual-focus lenses work best, and most often, the sharpest 50mm that a manufacturer offers, but some others work well – I’ve had quite good results with an M42-mount Vivitar 135mm f2.8 (pictured.) Macro bellows were used for years and can be obtained fairly cheaply sometimes, as long as you don’t mind obtaining (or making) adapting rings for your camera and lenses – I’ve glued together body and rear lens caps, with appropriately cut out holes for light passage, to adapt bellows for different lenses, as well as purchasing dedicated adapters.
Lens Reversing. Taking a wide angle lens and using it backwards in place of any other lens can actually produce some pretty significant magnification, and the results depend on the lens itself, without any decent way of predicting. This only works with wide angle lenses (typically no more than 35mm focal length, but 28mm is better) because they’re made to capture a broader field of view, and this is necessary to cover the film plane when used backwards. There’s no light loss, but, all automatic control is lost since there isn’t any contact for focus or aperture control, barring devices intended for this specific purpose (only useful for manufacturers that have all-electronic lens controls.) So, manual focus, and no aperture control unless you close it down manually – this is why using certain older manual focus lenses can work better, because their apertures can often be stopped down with a little lever on the base, and sometimes with a dedicated switch. It can be awkward, but at the same time, produce some pretty high magnifications.
I have been using a reversed Sigma 28-105 for years now, where the zoom also allows some adjustments to magnification and working distance. The aperture had failed, so I’d removed the motor for this from the lens and manually set it for roughly f16 permanently – while this helps with depth-of-field, it also means that the image in the viewfinder is perpetually dark, requiring very bright light (usually supplemental, like a flashlight) on the subject to even pin down sharp focus. It’s a little awkward, but it still serves pretty damn well.
Lens stacking. An esoteric one here, this involves using a sharp 50mm (usually) lens reversed onto the end of a medium to longer telephoto, generally 150-300mm, which produces a significant magnification. It requires a lens stacking ring with the right threads for each lens, usually not too expensive. Aperture control at least remains because of the use of the telephoto, but edge distortion is exceedingly common, and vignetting can occur easily, darkening the corners in a circular pattern. Best for use of very specific areas, right in the center of the frame, because that’s often the only area that is dependably sharp, but a quick and dirty way to achieve high magnification.
Actual microscopes. This is its own field, photomicrography, and can be exceptionally tricky. First, you need a real microscope, and these are usually not found cheap (I lucked out significantly at a thrift shop once, but I had to rig my own lighting system.) After that, it simply requires an inexpensive adapter to fit the camera to the eyepiece, but the camera will achieve significantly less magnification than the microscope eyepiece does. Aperture control is nonexistent, but depth-of-field is too because this is the nature of microscopes – expect only the focus point to be sharp. This is where taking numerous frames, all focused at different distances, and using image-stacking software comes in, combining the sharp portions of each frame to fake a higher depth of field. Naturally, your subject matter is either completely stationary or limited to a very small area (like microscopic subjects in a slide well or under a cover slip.)
Microscope objectives with camera adapters. The only one of these I haven’t actually tried (yet,) this involves using the lower lens of a microscope, the one just above the slide, with an extended adapter for the camera. Focus is strictly by working distance, light falloff is significant, aperture control (and thus depth-of-field) is nonexistent. Yet it’s also one of the cheapest ways to produce very high magnifications – as long as you can make or find an adapter.
Combined options. Most often, this is using a reversed lens with an extension method, but I’ve also used extension tubes with dedicated macro lenses just to boost magnification that much more. There’s also the option of using an enlarger lens with some extension to allow for full coverage at the sensor plane. You’re courting various issues by doing this, notably distortion and aberration, and also know that any of these not perfectly aligned will fudge up the results.
So, there are plenty of options to get those close pics, for just about any budget. Results will vary, sometimes in surprising ways, and a lot of it depends on what you’re trying to do and what subjects you want to tackle. But it can be fun just trying, and you can easily find new methods to add to your repertoire. Have at it!
While this was with the 780nm filter, you can see that the dynamic range is closer to the results with the 720 in digital, just lacking color – easy to tweak into a full range by deepening the lower ends (or using contrast filters in the 
