Near-Macro Photography in the Field

Yesterday I mentioned that I would have something to say about my recent adventures in closeup photography. I wouldn’t call myself a nature photographer at this point but I’m an amateur (very amateur) naturalist and really like taking photos as a way to bring “samples” home without actually bringing samples home. Being able to get very close to natural details is important, both because many subjects are just really small and the intricacies of larger subjects are fascinating.

There are a few different ways to get photos at the macro (micro, if you’re a Nikon user because they have to be different) level:

– Invest in a true macro lens (a.k.a. the real way)
– Use extension tubes1 and/or teleconverters on existing lenses
– Reverse-mount lenses, either directly to the camera or on another lens
– Add screw-on closeup lenses to an existing lens

The only method I haven’t tried so far is the first, because I’m difficult like that. But each has their own benefits and drawbacks. Definitions: true macro means 1:1 magnification, the subject being recorded on the sensor/film at life size. This means that on 35mm film or a full frame camera, a subject 36mm long would fill the frame horizontally, edge to edge. That is really, really close when you consider that 35mm film and modern digital cameras can produce good prints up to 20 inches wide, at least. You can see examples at any of the many macro lens groups on flickr.

Dedicated macro lenses get you to true macro magnification with no fuss and all of your camera’s automated features intact. They’re the easiest, but also most expensive, solution. They’re especially great for studio work, and can even be combined with some of the other techniques to go beyond 1:1, but are all prime lenses. The problem here is that you’re probably going to want to get shots at a variety of focal lengths, maybe some wide angle landscapes and telephoto landscapes, or use the compression of a longer focal length to blur the background in one shot but the wide depth of field of a shorter length to keep everything in focus in the next. Unless you’re carrying multiple camera bodies you’ll eventually want to swap lenses, and as much as I love using primes and can deal with changing lenses in some situations, out in the woods or on a windy, bare mountaintop are not those situations. So, on a short trip where you only want to take macro photos, a dedicated macro lens is a great idea, but on a longer hike, not so much, you’ll want a general-purpose zoom.

Extension tubes and teleconverters are essentially a cheaper way to get to 1:1 with lenses you may already have, to get them to pull double-duty. I’ve written about using extension tubes for macro work before, as an inexpensive (in this case under $50) way to get 1:1 or higher magnification. The problem is, teleconverters and extension tubes go between the camera body and the lens, so you’re really stuck with the same problem as above, unmounting the lens if you want to do anything but closeup work. Another problem is that you lose light — sometimes multiple stops worth — with tubes and teleconverters, which means increasing your ISO and thus ugly noise, to maintain the same aperture and shutter speed.

Reverse mounting a lens to the camera body, especially a normal prime lens, is an extremely inexpensive and efficient way to get very high magnification ratios if you already own a suitable lens2. However again that means swapping lenses if you want to do anything else, but there’s another solution; reverse mounting a prime lens onto the end of a zoom lens. This lets you work very close without having to take the zoom off your camera. I have tried this, that example is the Canon 50mm f/1.8 reversed on the 28-105mm USM at 105mm, giving somewhere around 2x (2:1) magnification3, but you can see that there are problems with image quality. You can do some math here and try a setup that gives less magnification and less distortion4, but in my experience, trying to do so with any reasonably working distance at a reasonable cost and with any convenience is very difficult. But, if you already have a fast prime to reverse onto a general-purpose zoom, reversing rings are under $20, so give it a shot.

One other approach I didn’t mention above that I’ve tried is finding a jack-of-all-trades lens, which to my knowledge is sort of like a unicorn who can do your taxes and poop out hundred dollar bills5. In my case it was the Tamron SP 60-300mm (23A), which impressively magnifies to 1:1.55 (about 2/3x) natively, along with a great zoom range of almost normal to telephoto. While it gives very good near-macro results, 60mm is just not wide enough, the lens is just too heavy, and manual focus is a little too tricky in critical situations, especially at 300mm. It’s a great lens though, and there may be others out there that can work for you; some standard zoom lenses will go to 1:4 or so which can be plenty for some purposes.

Closeup lenses are built just like filters, they screw on to the front of your lens. This means you need to get a closeup sized for your lens filter diameter so the same closeup may not work across multiple lenses, but it also means that you can add magnification without unmounting your lens. They work well on zooms, so there is none of the restriction or having the fixed focal length of a dedicated prime lens, none of the light loss of tubes or teleconverters, and you can easily choose between stronger or weaker magnification and avoid the extreme distortion of reversing lenses. They’re as small as standard filters and thus easy to carry along, much easier than packing another lens.

So, if you haven’t figured it out yet, I’m telling you to use these closeup lenses.

There are two basic types of closeup lenses, single-element and multi-element. Single-element lenses are very inexpensive, but at stronger magnifications blurry distortion becomes quickly evident, especially at the image edges. Multi-element lenses help solve this problem and return very impressive image quality but are much more expensive; a set of four single-element lenses can be had for under $20, while something like the Canon 250D goes for around $75 and up6.

Closeups are rated in diopter strength, listed as +#, a higher number being stronger magnification7. I find the +4 lens to be a sweet spot, enough magnification to show some good detail without degrading the quality of that detail.

Woah, I haven’t included any photos in this post yet? On my photoblog? Okay, let’s fix that. These are all taken with the Canon 5D and 28-105mm f/3.5-4.5 USM, with a Zeikos +4 closeup lens included in a $15 4-lens set:

Bennett Hill, Clarksville NY
Ant and Damselfly, Taughannock Falls, Ulysses NY
Poppy

You can see a few more in a slideshow. What you may notice is that these are not quite as close up as some of the examples of other techniques. I’m getting around 1:2 (1/2x) magnification, not true macro closeness, and going much stronger than +4 really begins to degrade image quality. I find this to be the best compromise; it’s rare that I need to go stronger than this for the sort of visual field notes I’m taking, and carrying the closeup set lets me throw another closeup on to get +6 or even put on the +10 and take the hit to edge detail. I find this acceptable for the convenience of carrying around only a lightweight set of small screw-on lenses and being able to quickly switch between a general-purpose zoom and near-macro work.

A couple of notes about using closeup lenses. The diopter is additive and lenses can be stacked, so a typical 4-lens single-element set with a +1, +2, +4, and +10 can also give you, say, +3, +6, or +178. More importantly, when using a zoom, once you have mounted the closeup lens your focus ring doesn’t work how you may think. Instead of focusing closer or further, it changes the working distance of the lens. So, in my case, on the 28-105mm zoom, the closeup lens makes 28mm the least amount of magnification and 105mm the greatest, while what is normally the shortest focus distance now gives the shortest working distance and the longest focusing distance (infinity) gives the longest working distance. This is counterintuitive because normally closest focus distance gives the most magnification and in fact on this lens that is actually marked with “macro” on the distance scale. With the closeup lens on, the difference in magnification is negligible, again the focus ring only changes your working distance!

One final sidenote: a low-power diopter, +1 or +2, can have some application in portraiture. When you want to greatly blur your out of focus areas, it will drastically reduce your depth of field, and selecting a moderate focal length in your zoom range (in my case around 50-70mm) will not magnify the image greatly, so you’re not filling the frame with your subject’s pupil or anything. Going a bit stronger will start to give a soft-focus effect outside of the very center of the image9, so get creative; shoot your subject at an angle and put the close eye right in the center of the frame, and it remains sharp but skin gets softer and appears smoother toward the edge of the frame.

That’s what I can tell you from experience. The dedicated macro lens is the easiest way to get true macro magnification (while I haven’t experienced that directly, I can tell you the other ways can be a huge pain). Extension tubes and teleconverters can work wonders and get you really close but mean either only shooting macro or swapping lenses. Reverse-mounting can get you into the extreme macro range but means either again unmounting lenses or dealing with some severe distortion issues without lots of trial and error and possibly expensive, high quality lenses, which you have to carry with you. But closeup diopter lenses are easy to carry, don’t require removing a general-purpose zoom, and inexpensive ones can give surprisingly good results for the money. If I’m going to be hiking for three days, I’ll take the inexpensive, lightweight solution even if it means a slight hit to image quality, thanks.

1Or bellows, but it’s difficult to find new bellows setups for modern DSLR systems, you’ll more likely end up with a Frankensteinian adapter setup.
2Fast standard primes work great, if you have something like the cheap Canon 50mm f/1.8, give it a shot just for kicks.
3Divide the primary lens’ focal length by the reversed lens’ focal length to get an estimate of magnification strength.
4Faster zooms like the Canon 24-70 f/2.8L will give better results, the wider the primary lens’ aperture the less distortion toward the edges. But those lenses also cost about the same as the monthly rent on some New York City apartments.
5That is, it doesn’t quite exist.
6And are increasingly tricky to find, and may only come in a single strength for your lens type.
7Like extension tubes, they effectively shorten the minimum focus distance as well as narrow the depth of field, sometimes drastically.
8Stacking four closeups will probably lead to strong vignetting as well as massive amounts of distortion. When stacking, put the lowest diopter power on first.
9high-power diopters, especially single-element ones, exaggerate coma toward the edges of the frame, which provides that “dreamy”, soft effect that some people try to get with really cheap lenses or software emulation of those lenses (*cough* Hipstamatic *cough*).
10Yes, I love footnotes.

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4 thoughts on “Near-Macro Photography in the Field

  1. D. Lambert

    Very interesting. I take a fair number of my photos while hiking, too, and the last thing I need is more lens changes, so this might be worth looking into. On first thought, I’d probably pick up lenses to fit my Canon 70-300 IS USM, as I usually need the stand-off distance for any sort of flying critters.

  2. B

    Thanks for commenting. That should work but there’s actually some weirdness that comes from using internally focusing zooms, which I barely understand, but it’s why turning the focusing ring chnages the working distance. Lenses that focus internally do not actually function at the focal length marked on the lens when approaching the minimum focus distance. Here’s a great explanation with examples. As I understand you should definitely have more distance, but even with the 28-105mm I’m getting around a foot or so at 105mm and infinity focus with a +4 diopter. The 70-300 IS USM actually takes the same 58mm filter so you should have no problem finding the closeup lenses, but I highly recommend springing for one of the multi-optic ones if you can. I believe you’d be looking at the Canon 500D (yes, they brilliantly gave it the same name as one of their cameras), and Raynox makes some highly rated closeups, start by looking at the DCR-150. The only other concerns are vignetting which can be more pronounced at longer focal lengths, and the extremely shallow depth of field you’ll get at 300mm, even stopping down it may be tough to focus — though there’s a good chance autofocus will still work, or at least AF-confirm in MF mode.

    Good luck!

  3. Tim

    Whoa. This must have been a bear of a post to put together! This is one area of photography that I love, and I often struggle with getting the results I’d hoped for. I also have gone the route of the closeup lens attachment. The ease of screwing it on and off my 55-200mm is enough for now until I can drop a wad of dough on a true micro (yeah Nikon!) lens. Some examples: http://tinyurl.com/43ncw6h and http://tinyurl.com/5s87fgz

  4. B

    It’s been over a year since I started experimenting, so this has been a long time coming. The closeup lenses are really the best compromise I’ve found, considering I may be spending multiple days in the woods and 8+ hours hiking, having to carry the gear and keep up with people. Those are good examples, doesn’t look like you need the dedicated lens yet…

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