Knowledge Base

Buying Macro Lenses

It is late spring, and the world is awakening after what feels like a long, dark winter. Outside, early flowers paint the garden with much needed colour and the first honey bees are starting to appear. In the house, our resident ant colony is busy seeking out food, some of their opportunistic members venturing into the bottom of the Amazon parrot’s cage for morsels of dropped fruit.

We have lived with regular ant invasion for more than two decades, from their post winter foraging to the calamity of airborne re-colonisation attempts on humid August afternoons. Every year I try and restrain their activity, but their industrial prowess continues to defeat me, proving that the resilience of the little buggers takes more than regular dowsing of insect powder and occasional squirts of No More Big Gaps to curb.

It is thanks to my own stupidity that we live with ants and, because of this, I receive no sympathy when their annual spring campaign begins.

Let’s go back to the summer of 1993, the year before Ethan was born. Apart from planning his arrival I, unbeknown at the time, was simultaneously planning for our conservatory to become the base of insect activity of almost biblical proportions. My photographic interest had taken me down the macro path. Realising there were fascinating worlds within worlds waiting to be discovered through the appropriate lens, I began reading up on the subject with view to buying a dedicated lens and supporting accessories. It became clear to me that there were several budget ways of achieving closer focus than supported by my lenses, but my requirement was for a dedicated macro lens, not a token gesture made by a ‘jack of all trades’ optic.

Macro lenses come in many focal lengths and magnifications. First it is important to understand exactly what a macro lens is/does. Many lenses with the ability to focus closely are branded ‘macro’, but in a strict sense, only those that achieve a magnification of 1:1 (that is produce life size images on the cameras sensor or film plane) and above are true macro lenses. Anything below this is simply ‘close focus’, although a lens that delivers 0.5 x life size can be considered macro as it is often used in conjunction with extension tubes to realise a 1:1 ratio.

Below are a few points worthy of consideration is you are thinking of adding a macro lens to your collection. They are based on our own experience, by no means exhaustive, and assume that you are past deliberating over using accessories such as reversal rings or close-up filters.

  • Subject Matter

    The chances are that you have already decided this, which is how you settled on buying a macro lens. Was it the transient backlit luminance of moss fronds, a resting dragonfly or the delicate beauty of a bird feather that attracted you? It is important to think beyond the initial attraction and look deeply at potential subject matter and how you wish to portray it. Environmental macro typically requires lower power which will leave you wanting if you also wish to photograph insects in close proximity. Similarly, still life does not scare when you get very close to it, whereas a resting dragonfly does, so think carefully on this before parting with your cash. Good quality Macro lenses are not cheap and the potential for getting it wrong at this stage in the buying process is high if the intended use is not understood.

  • Focal Length

    Focal length is of equal importance to subject matter as it has the potential to impact the subject greatly. For example, a lens with a 50mm focal length requires you to get close at its maximum magnification. That resting dragonfly will be long gone before you can look through the viewfinder. A 90 or 135mm lens increases the working distance, allowing skittish macro beasties to remain calm and unthreatened. That is not to say a 50mm lens should be considered inferior; static subjects such as leaf detail or gemstones are perfect. For many years, my own preference was for something in between i.e. 80mm. At life size I found it a good compromise for many of my subjects. Today I use a 60mm although using it with an APS-C sensor provides a 90mm view while allowing me to retain a good working distance.

  • Magnification

    Magnification often given first consideration with many photographers wanting the most powerful solution possible. In love with the idea of capturing stunning images of an insect’s compound eyes, the reality is far more difficult when put into practice. For general subject matter, I find that a lens allowing up to life size magnification addresses more than 95% of my requirements. Beyond this, we are entering a more specialist world full of wonderful surprises.

    For the purpose of extreme macro work, I used two high power lenses; a 38mm, giving up to 5 x life size results, and a 20mm that almost doubled this. When used with the correct subject, results are surreal and other worldly, revealing details that are hidden from normal view. Working at these magnifications is difficult and focussing becomes extremely critical due to depth of field being very shallow, even at smaller apertures. Lighting complexity becomes exponentially more difficult also, as does support of the camera and lens. Rewards are hard earned but unique. Based on my own experience, I would not recommend high magnifications as a starting point – begin at much lower levels and develop the necessary skills that can be used as a springboard into higher power work.

  • Aperture

    Shallow depth of field is an inevitable constraint of close-up photography, which increases as magnification escalates. This challenges the practical aspect of high speed lenses. My 20mm was an f2 and, used at this value at 9 x life size, provided me with around 1-2mm depth of field in which to accurately focus. For most practical purposes, I stopped the lens down to f5.6 or f8 to give composure a sporting chance. A fast macro lens offers little in this area but is valuable as a lighting aid. Subjects can often contain a lot of shadow or be dimly lit – the more light a lens allows, the easier it is to select a good focus point. Consider also if the lens doubles as a short telephoto or standard lens as a bright aperture allows greater depth of field control for artistic purposes.

    A macro lens with a slower maximum aperture such as f3.5 or f4 will be significantly less expensive, smaller and lighter, so should not be overlooked if you are more budget conscious. Almost without exception the results will be as good as their faster siblings.

  • Manual or Autofocus

    Macro lenses do a reasonably good job of autofocus at lower powers, but as light falls and magnification increases, selecting the correct point of focus leaves automation somewhat lacking. Always look for a lens that has a manual focus override as this contributes greatly to creative freedom, especially once working at life size and beyond. Many higher power lenses are manual focus only, and the reason becomes very obvious when using them. Manual focus allows micro adjustment that autofocus is simple not capable of. When working with tolerances whereby 1mm becomes critical, focus accuracy is a task best performed manually. My own preferred method is to set the lens to the desired magnification and use a focussing rail to adjust focus accordingly.

There are many more considerations when venturing in to macrophotography, but it is the purpose of this document to cover those that are lens specific.

Returning to the opening paragraphs of this guide, do not let your enthusiasm carry you away like I did. We had several active ant colonies in the garden and I had tried unsuccessfully to get some good pictures of them. In a bizarre moment of madness, I decided to dig a nest up and transport it to a table in the conservatory, which would allow me to get up close and personal to by subjects. The ants shared a very different opinion which I should have realised as they made their way angrily up the spade handle as I ran across the lawn with their home.

By the time I had placed the nest on the table the ants were pretty incensed, pouring out in their hundreds to see what was going on. Blind to the problems that my actions had triggered, I focussed (no pun intended) on the task in hand and attempted to photograph the seething mess before me. Anyone who has taken pictures of insects will be very aware that they seem to move much faster when being scrutinised through a macro lens… even a snail leaves the frame faster that it is thought possible.

In an attempt to adjust composure, I decided to move my tripod back a little and it was at this point I realised my mistake; livid ants were everywhere and covered the carpet, speedily conquered the sofa and climbed the legs of both me and my tripod.

The clean-up operation took a couple of hours and consisted of the hoover and insect powder. By the time I had relocated the nest back to its original place in the garden, it was about as lifeless as a post eruption Pompeii. Congratulating myself on 1) limiting the problem to just the conservatory and 2) managing to deal with the problem without the rest of the family becoming aware, I decided that all future macro pictures involving insects would be taken outdoors.

Time soon revealed that my clean-up operation had not been as thorough as I thought. Some of the more pioneering ants had made it to the edges of the carpet and founded new empires in the recess where carpet meets conservatory frame. And there they remained, their successors reminding me annually of one of the dumbest photographic mistakes I have made.