When pursuing macro photography, there's always the urge to probe deeper, get closer. We want to marvel at the infinite layers of detail offered by the world around us. Doing this on a budget, however, is a challenge. Microscopes, lenses, adaptors, specialised lights, slides, solvents, dyes: the list goes on and can quickly spiral into the thousands. So what can you do on a budget? In this article, I'll show you a type of micro setup you can create with mostly with the gear you already have.
1. Laying the Foundation
Quality microscopes are very heavy. Why? Not because they have 8-inch lens elements in them, but because the body is built to be heavy. At extreme magnifications, the tiniest tremor from someone shifting their weight in the room next door can make the whole field of view shake wildly. So floors are concrete, benches are bolted down, and the microscopes are very heavy.
If you're going to pursue low-budget micro photography seriously, filling a bucket with concrete as a base would be a good first step. In the meantime, try to work somewhere with a solid concrete floor, like a garage or basement, or perhaps build a small brick platform. Anything with a lot of weight to it is good, as it's hard for small vibrations to move it.
Those of you stuck with a couple of chairs or breeze (cinder) blocks should lay down a couple of sofa cushions to sit/kneel/stand on. These will absorb most of your usually unnoticeable vibrations and make focusing a little easier.
Once you have a base, you need a platform to point your camera at. This needs to be transparent, so you can light objects from underneath as well as above. I use tabletop glass because we have a few sheets in the house from various places and it's easy to clean when I need to get it in the photo. Plus unlike microscope slide glass, it won't crack when your metal-mount lens accidentally drops into it!
2 Light It Up
You're going to need a lot of light for focusing. A 23-27W (100W equivalent) CFL will just about suffice if it's in a reflector and you turn off the exposure simulation on your camera's LCD. The image will be extremely noisy when zoomed in, however. If you can, use several bright lights from various angles.
Do not use tungsten lights or your strobes' modeling lamps. Sheet glass, even table glass, isn't treated to withstand the extreme temperature fluctuations and will crack. Depending on the way you're set up, this could potentially be very bad news for your feet.
For the actual exposure, flash is the way to go. Whether that's a speedlight or strobes is up to you, but I've personally found the speedlight more versatile in its positioning, and because it can be placed so close, it becomes a relatively soft source. I sometimes use a couple of low power strobes as general fill, but because they're so bulky and my light stands don't fold far enough, they're not a whole lot of help.
One to three bare speedlights and some method of positioning them (the foot they came with, boom arm, Gorillapod, whatever) is definitely my recommendation.
Once you have your focusing lights and exposure strobes in there, there isn't going to be a whole lot of room to get your camera in! You're also going to want to light some subjects from the bottom, and some more opaque, textured subjects from the top, so make sure you retain the ability to move lights and flashes around.
Now we're getting down to business. How exactly are you supposed to get such crazy magnification with regular photography lenses? You may have heard of reverse lens mounting. We'll be doing an advanced version of the that, where you don't just reverse-mount a wide-angle lens, but you do so onto the front of a telephoto lens! This creates an unwieldy frankenlens, sure, but one that's capable of resolving separate cells in a plant.
I'm doing it with an 18-50mm f/2.8 for the wide angle, and an 80-200mm f/4.5-5.6 from my film days. Not the greatest combination in quality, but since I don't happen to have a 70-200mm f/2.8L sitting around to hitch my standard crop zoom to, it is what it is.
The better your glass, though, the better your images. Go as good as you can, because once you start zooming in at this scale, you start to see the breakdown in lenses with cheap optics very clearly.
To connect your lenses, you need a male-to-male filter adaptor, likely a stepping version. Mine is a 72mm to 52mm, which was about $3 from Hong Kong on eBay. It's probably cheap metal, but turned out to be nice and solid thus far with no signs of wear or stripping for around three years. I haven't had any issues hanging the heavy f/2.8 on there.
It's also fairly critical that your optics are clean, both front and rear elements on both lenses. A minute dust particle can show up in the image as a large grey blob, obscuring your subject.
If you really want to punch in, get a bellows or extension tubes and a good-quality teleconverter, though I'm assuming most macro photographers will have at least one of these!
4. Camera Mounting
Naturally, you want the tripod to be as heavy as possible; it doesn't even necessarily have to be a photo tripod. It could be a heavy-duty telescope, surveying or video tripod. It just needs to be bulky with smoothly moving parts and as little play when locked down as possible. Ideally, it should have a centre column that has a rack and pinion (geared column) to set the height, though this is unlikely on most stills tripods. On top of that, I'd strongly recommend macro rails.
Trying to frame and focus with the camera by shuffling tripod legs or jerking the pan/tilt head around is difficult and frustrating (though possible, admittedly). Spending the $25-90 on a cheap, but reasonable quality, set of rails is definitely worth the cost in saved time and enjoyment. But again, if you're going from macro to micro, I'm generally assuming you already have a decent set of rails.
Your subjects can literally be anything. Many things are interesting on the micro scale, though it's always fun to start with the usual; leaves, petals, dead bugs, skin flakes... Anything translucent, textured, or preferably both is fair game, though you may discover a texture on objects which appear smooth, so explore and experiment!
There are at least two stages to focusing, depending on your setup. My personal preference is to lock (or duct tape, in my case) the telephoto at its minimum focusing distance, and then rely only on the reversed wide-angle's focusing ring. You use the tripod column (I'm almost always shooting vertically) to set the coarse focus, then use the reversed lens for fine focus.
If you have focusing rails, it's even easier. You just set both lenses to their minimum focusing distance and use the tripod column for coarse focus and the rail for fine focus. This will also allow for relatively easy focus stacking, which is useful since the depth of field at such high magnifications is negligible; somewhere in the region of 50-100 microns is my estimate.
This is the most frustrating part, as it's so intertwined with focusing. I'm using a T3i as its 18MP resolution allows for more cropping ability than my 10MP 40D. I use the articulating LCD to be able to sit or crouch, rather than stand, since this is a more stable position and produces less vibration through the floor.
I use a remote trigger, so I don't have to touch any part of the apparatus during the exposure. I've found that IR remotes can be reflected off the glass, so triggering is less awkward. I also tend to use mirror lockup to further reduce the likelihood of unwanted vibration.
This vibration is actually generally not harmful to the exposure in terms of motion blur, as I'm using flash rather than several second exposures with continuous light, but after all that careful framing and focusing, knocking the camera by even half a millimetre will completely alter the view. That said, you don't need to be too paranoid about touching the camera, as most light touches will just bounce back to its original position.
Setting the aperture on modern lenses, of course, will require the depth-of-field preview trick, since there isn't usually a separate aperture ring. So before shooting, put your wide angle lens on the camera in aperture priority mode, set it to whatever you're using (I use around f/11 for a reasonable tradeoff between depth of field and diffractive effects).
After it's set, hit the depth-of-field preview button, and while holding it down, release the lens and twist it off. The lens will hold the aperture you've set. Do the same to the telephoto lens, if you're going to attach bellows/tubes or a teleconverter which don't have electronic contacts.
If you aren't on a solid concrete floor, it'll be possible to control a certain degree of framing and micro-focusing by shifting your weight around. This is better experienced than described, so experiment.
Magnification is controlled by the zoom settings on the lenses. The longer the telephoto, the more it magnifies. The wider the wide-angle, the more it magnified once reversed. I let my 80-200mm drop down to 200mm, and have my 18-50mm zoom-locked at 18mm. This gives me maximum magnification between the two lenses; somewhere in the region of 12x, as I recall.
Adding the 2x teleconverter doubles this, and then the extension tubes allow the whole rig to focus more closely, bringing the total magnification up even further.
The magnification of a particular configuration of lenses and settings can be calculated using a known object. Say you have a sewing needle that you know is 0.60mm in diameter, and when focused it takes up two-thirds of the screen horizontally. Knowing the dimensions of your sensor (the T3i's APS-C sensor measures 22.3mm by 14.9mm within the imaging area) allows you to multiply, in this particular instance, 22.3mm by 2/3, which is 14.87mm. That's the "image size" of my hypothetical object. Divide this number by the actual size of the object to know how many times it has been magnified. 14.87/0.6 = 24.8x magnification, which happens to be about what I get at 18mm/200mm/2x teleconverter.
9. Examples and Results
I know you want to see the consistency available with this somewhat jerry-rigged method, so here are a few of my results with various subjects:
10. Observations and Improvements
So, does this method replace an expensive 400-2000x magnifying trinocular microscope with a several-hundred-dollar DSLR adaptor and a 300lb lab bench to put it all on? Well, no, of course not. But for hobbyists, enthusiasts and full-time macro photographers, this is a good way to experiment further by using what you most likely already have lying around. Even for scientists who have the pro gear at work, but would like a little something to fool around with at home.
How would I go about improving it? The first thing I'd probably do is build a CNC gantry with screw drive motion control (using wheels, not CNC electronics) instead of the macro rails. This would allow me to mount the camera in the centre of gravity rather than leaning off one side, and the whole rig could be set on top of a concrete block with an inset hole for a CFL/LED PAR and speedlight.
I could then tether the camera to a computer for the liveview (something I used to do regularly with this method), and precisely control the position of the camera in three dimensions. This would cost a little bit, but not even close to the price of a camera-microscope adaptor, never mind a microscope itself. The other thing to do would be experiment with other lens lengths in various combinations.
It's a Small World
I hope you enjoyed this little foray into the world of the very small on a budget, and hopefully it gave you some ideas for your own goals. It's really not too difficult to get into low-power microscopy with only a DSLR and regular photo/macro gear. With a little patience, you can create some fantastic images. I've certainly had a lot of fun using this technique over the last few years!
Questions? Comments? Hit up the comments below!