Macro photography, part five

I got my timing down the other day, and caught a set of lady beetle eggs as they hatched. The eggs are 1.2mm in length – yes, I have a loupe with a micrometer scale – so the details you’re seeing here are pretty fine. As you can see, the larva are visible through the translucent shells.

Hatching isn’t quick by any stretch, but it can still happen entirely while you’re inside eating lunch – the timing between these two photos is 51 minutes. The different appearance of the background is from using both a different position and different settings for each. For the second, I opened up the aperture a stop to f16, dropped the shutter speed to 1/80 second, and got the (very bright) blue sky in the background dimly. Most of the lighting comes from the flash, but some of the ambient color of the sky came through with those changes. This is definitely pushing the envelope of useful settings for macro work, especially at this high a magnification. I was unable to get a tripod into a useful position, so this was handheld, and at 1/80 second it’s actually very easy to twitch the camera enough during the brief time the shutter is open to have blur show up in the image. The flash duration is extremely short and will produce a sharp image, but anything else bright enough to come through without the flash’s assistance, such as sunlight reflections, can streak in the image, producing a bizarre effect.

Now, for some pointers. Both of these images were obtained with non-standard means. I used a Mamiya 45mm f2.8 lens intended for the M645 series of medium-format cameras, mounted to my Canon EOS Digital Rebel (300D) camera by means of a reversing ring. This is a simple and very inexpensive metal ring that has the standard Canon lens mount on one side, and threads to fit the filter mount of the Mamiya lens on the other; this means the lens mounts backward onto the camera body. By using a wide-angle focal length like 45 or 35mm, you produce a very-high magnification macro lens with a surprisingly low amount of distortion. You can do this with any make of wider-angle lens, but the best results that I’ve achieved by far have been with the Mamiyas. In my cases here, I boosted the magnification even more by using them on a 20mm extension tube, between the adapter ring and camera.

Of course, there is no autofocus, and in fact no focus at all; since the lens in intended to produce a sharp image on the image plane (where the sensor or film sits,) by using it backwards you have one fixed distance where everything is in sharp focus. Even twisting the focus ring does almost nothing – I just keep it locked at infinity since that’s where the highest depth of field is achieved. There is also no aperture control from the camera; the lever that closes the aperture is pointing out the new front of the lens at your subject. And the EOS line has electronic aperture control anyway so it simply won’t do anything with any lens not intended for this. Trust me when I say that you do not want to shoot anything with the lens wide open at f2.8, the default of the lens, because depth-of-field is too short to see anything not perfectly flat to the camera. Even at f16, you can see from the second photo that DOF is somewhere around 2mm or less.

What to do, what to do? Well, with any lens intended for mechanically-controlled apertures, there’s a lever or pin on the body-side of the lens (now pointed towards your subject) that closes the aperture down. All you really need to do is push this lever over to close the aperture, right before you trip the shutter. Seen here, my left forefinger sits atop the pin ready to close it down when I get sharp focus. The M645 lenses have another option, which is a manual/auto switch on the side which will also close down the aperture – this is sometimes easier than putting your finger in front of the lens.

You can also see the flash rig I use. This is a Bogen/Manfrotto 330B Macro Bracket (also seen here) which allows a fairly wide range of flash positions with the swing arms and tilting camera platform, and it can even mount onto a tripod. Since the focusing point of a reversed lens is very close to the end of the lens, the flash must be positioned where it can illuminate the subject effectively – leaving it in a normal position on the hot shoe atop the camera will almost certainly result in blocking the light with the body of the lens. The flash is attached via an off-camera cord to the camera, allowing for TTL work, though there’s a good chance with the camera receiving no information about the aperture setting, TTL flash will not work at all. I’m simply shooting at manual output here; the Metz 40 MZ-3i strobe is manually adjustable over a wide light range. A few experiments told me what power I needed for any f-stop. For some subjects, a diffuser or small softbox may work a lot better.

I’ve also done no small amount of work with a Mamiya 80mm macro lens, again for the M645 line, this time mounted in the proper orientation. This lens requires an extension-tube specially made for Mamiya lenses to achieve the macro ‘standard’ of 1:1 ratio.

Let me digress here a moment. 1:1 ratio is often considered “true” macro, and what it means is it produces an exact-size replica on the film/sensor. Take a photo on slide film of a coin and lay it alongside the coin itself, and they will be the same size. While this is much better than 1:2 or 1:4 ratios, basically, it’s almost meaningless. You’re going to reproduce the image in a print or digital usage in some other size anyway, so what’s adequate for your subject is enough. For the egg photos above, I’m achieving a lot more than 1:1, and it’s necessary to see something that small.

The 80mm macro, while not producing as high a magnification as the reversed 45mm, allows a better working distance, which can help with spooky subjects. Looming over insects with the camera and flash rig can often scare them off, or even to the opposite side of the leaf, so sometimes the greater working distance is necessary. I can also leave the flash mounted to the hot shoe with this lens because of that (granted, the flash head does angle downwards slightly if needed, and it is.) Because the aperture lever is now buried behind the adapter, I have to use the manual/auto switch to close the aperture, but it can be easily reached with my left thumb.

It is possible to buy adapters specifically for mounting M645 lenses to EOS bodies, but they’re more expensive than they really need to be, unless you have a camera that requires focus confirmation through the lens (every camera that I’ve seen allows this to be shut off in the custom functions, but my knowledge is by no means exhaustive.) I took the cheap route, however. I drilled out a Mamiya lens-base cap so it was more of a ring, and mounted it with epoxy to a reversing ring of a matching size – total cost about six dollars. The reversing ring is easily distinguished in The Girlfriend’s photo here, being darker than the base cap, while the base cap is reflecting my arm faintly right at image center; everything else is the Mamiya lens itself (actually, the Mamiya extension tube is sits between the base cap and the silver ring, and the manual/auto switch is visible right alongside my thumb.) If you do this, it helps to make a few reference points before gluing the bits together, so the lens is oriented the way you want it when it mounts to the camera.

Mamiya lenses are surprisingly affordable on the used market, well under half of what a dedicated macro lens for current digital cameras cost, and even more versatile. They’re remarkably sharp, and sturdy – that also means heavy, so bear this in mind when constructing your mount. While I’m used to it, The Girlfriend actually finds my rigs here too heavy to wield effectively.

There’s something else that you may have noticed in the two photos showing the full camera rigs: a little white doodad on a gooseneck. This is a device of my own manufacture, a three-LCD flashlight that can get strapped to the flash. Many of my photo subjects are active at night, so being able to see them is important, and no headlamp will throw light past the camera onto a close subject. The gooseneck light can be aimed right at the sweet spot of focus, making sharp images a whole lot easier; it’s even bright enough to work in shadowy areas in the daylight. Believe me, this is soooo handy for macro work, and it will increase your sex appeal and bring harmonious concord to the universe. Or am I overselling it?

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