Super Macro – When Going Small is Just Not Enough

So what is Super Macro?

It can mean different things for different shooters, but as a rule of thumb, regular macro goes to approximately 1:1 reproduction ratio. What the heck is that? That means that a subject the size of your sensor would fill your image frame. So on a 35mm sensor (full frame), a 35mm (1.32 inches) long nudibranch would fill image frame. Smaller sensors mean that a smaller subject would fill the frame at 1:1 reproduction. So is one way to shoot super macro a smaller sensor? Well, yes, but everything has its trade off as we will see.

So one description for Super Macro would be any magnification technique that provides greater than 1:1 reproduction, which would mean a subject smaller than the sensor would fill the frame.

Still confused? Then just know that there are always techniques for photographing or videoing stuff tinier than we ever imagined if you have the right tools.

So let’s look at the tools available to us in 2018.

How do we get big magnification without sacrificing quality?

This has long been a tug of war of sorts. Most traditional techniques of going beyond the capabilities of a high quality macro lens (on an interchangeable lens camera) usually meant giving up some sharpness, adding some chromatic aberration (color fringing), losing depth of field and working distance and often times a little distortion is added to the mix. But hey, we were shooting stuff that had never been seen with the naked eye and we were happy just to get the shot!

Options and techniques have increased markedly over the years – with mostly improved results, but there is not going to be one size-fits-all best case scenario for most people – both because of equipment differences and also because of different goals for different shooters. But there are pros and cons to most options and they are worth covering so each individual can make an informed decision. So let’s look at the big, I mean small, picture.

Traditional tools for increasing magnification underwater:

One of the more common techniques of the past – for interchangeable lens cameras - was and is Tele-Converters (Usually 1.4X, 1.7X, 2.0X) that are installed between the camera body and the lens. This definitely has an advantage over things like extension tubes in that tele-converters are “smart”, meaning they maintain auto-focus and other electronic functions of the lens while changing the effective focal length of the macro lens. Another advantage of T-Cs is that while the subject is “magnified” by the narrowing of the field view (40% with 1.4X, 70% with 1.7X, 100% with 2.0X), the minimal focus distance stays exactly the same as with original macro lens.

The down side? Once installed, it is on the whole dive. It might be too narrow to go from shooting anemone fish eggs to actually shooting the whole anemone fish. The other issue is image quality. You rarely get something for nothing and as the tele converter gets more powerful, image detail will start to suffer making anything stronger than a high quality 1.7X probably a poor choice. A T-C requires an additional extension for your macro port equivalent to the size of your tele-converter.

Traditional “Dry” Diopters

An inexpensive trick people have tried is using traditional lens diopters, +2/+4/etc., on the front of their macro lens inside the port. All diopters increase magnification by reducing minimum focus, but you also lose distance focus. So on a 60mm, 100mm or 105mm macro lens you will lose working distance and options when shooting a subject a little further away. On a longer macro lens in the 150-200mm range, this is not as problematic as the minimum focus distance is generally farther away than shorter focal length macro lens. Ultimately these diopters are limited in strength, reduce flexibility and often require an additional extension ring. So generally not a great Super Macro option.

Please note that using a “dry” diopter on the wet side of your port will produce very little magnification as the water on both sides will negate the effect of the diopter strength.

Close Focus Macro Wet Lenses

In the last 5-6 years, underwater close focus lenses have become very popular both for “regular” macro utilizing “normal” non-macro lenses of longer focal lengths and also for Super Macro when combined with good quality 1/1 macro lenses.

The vast majority of these lenses are made by combining two or more “dry” diopter lenses of different strengths and sealing them in between flat glass so that they maintain their strength. This definitely improves magnification and combining the lens with a quick release bayonet or flip mechanism made for a convenient system that allowed full use of the lens, plus extreme magnification (depending on strength) when desired.

Some of the problems with this technique are again that all diopters increase magnification by reducing minimum focus and therefor put you closer to your subject. This means that lenses that are already very close focusing like a 60mm macro on a DSLR or a 30mm macro on a Sony or Micro 4/3 camera won’t benefit much – if at all. And the stronger the diopter rating, the less room you have to light your subject as it gets ever closer to the port, even on a longer macro lens.

One other problem can be image quality. Close focus lenses do follow the “you get what you pay for” adage. Many manufacturers are using off-the-shelf diopters to make close focus wet lenses and the quality varies a lot. Beyond that is the problem of diffraction that happens every time water hits a flat piece of glass with air on the other side of it – the side effects include what many of us have seen, whether we know what it is called or not: Chromatic Aberration or “CA” for short. Anyone who has ever taken a picture of a purple anemone with a macro lens has probably noticed blue fringing around the tentacles. That is CA and every time water hits flat glass, a little CA is imparted. So if your close focus lens is just diopters between flat glass, then that means two more surfaces lowering image quality. This will partly explain why you will generally get better results with one stronger macro wet lens, then stacking two or three weaker ones as some people will do in their quest for ever smaller subjects.

On the other hand, the best water contact macro optics have no flat glass surfaces and are computer designed to enhance in-water image quality and help with working distance as well. This makes for a more expensive super macro lens, but the image quality improvement can be striking. Some can even make your super macro image sharper than the macro lens shooting through a flat port on its own.

It should also be noted that as a general rule, you will usually get greater useable magnification with a macro wet lens on a longer focal length macro camera lens than on a shorter focal length macro lens or conventional non macro lens.

An Unusual Option for Canon DSLR and EOSR

Canon makes a unique lens called an MP-E65mm F2.8 1-5X. This lens is NOT for everyone. It does not autofocus, it is useless for taking pictures of things far away. But it can offer impressive reproduction of a subject at up to 5 to 1 magnification. You can essentially select the amount of reproduction ration you want and then move the camera in until you are in focus. The more magnification you want, the closer you have to get.

Because this lens has such a limited scope of capability – it isn’t a recommended lens for most people, but it is super macro capable with no additional optics.

Making Super Macro Easy Enough to Try Often

In reviewing the options, most people will find that using high quality macro wet lenses are probably the most flexible and versatile option in more situations. But screwing and unscrewing lenses on your macro port underwater is a guaranteed way to discourage you from shooting super macro. It is just too inconvenient. We strongly recommend using a quick release bayonet mount or a well made “flip” mount. There are pros and cons to each option, but either one will make your effort easy enough to have fun with super macro any time you reach the limits of the lens you are shooting. You will probably never go in the water without one mounted on your macro lens – we certainly wouldn’t!

Other options to seriously consider are a good focus light, manual focus gears and an enhanced viewer to see the details – either an enhanced viewfinder or LCD magnifier if working with a compact.

Below are links to some of our favorite options. If you aren’t sure what will work best with your equipment and your goals, just let us know, we are here to help!