More on ‘macro technique’

I am not a photographer. I just take photographs. I greatly admire photographers who capture moments that no one else can and I wish I could do the same. However, I very much enjoy ‘the world of small things’ that my cameras and lenses allow me to explore. While, I have little talent as a true photographer, I take some solace from having taught myself how to take tolerably good macro photos. In this post, the first of several on macro technique, I have dared to share a little of what I think I may have learnt.

When I first started in the world of ‘macro’, I found the techniques described on the web and in some books extremely confusing. Indeed, one author often flatly contradicted another. Below, I use those contradictions to explore the techniques that I now employ. However, there is a big question that everyone considering macro photography needs to answer before they begin: why do you want to take macro photographs? I use macro photography for several purposes. Firstly, to collect images of insects and plants so that I can later sit down to identify them in a field guide. Secondly, I take pictures to allow me to see features of the things that I find so beautiful that I cannot see with my naked eye. Finally, I do it because it opens my eyes and reveals a hidden world that we spend most of our time ignoring – and I love it. My techniques are far from perfect, and some of my preferences like traveling with minimal gear, are designed to collect images for reasons other than getting to optical perfection heaven! Others use techniques totally different to mine and they may take better shots than I do. Below are the things that work for me.

Contradiction no 1. You need a sophisticated camera – any camera, even your phone will do.

Well, this wasn’t really a question for me, I just love optical technology and have worked with the best of it all my life so, I have always had an SLR or more recently a fancy mirror-less camera. It is true that you can take excellent macro shots with any camera and indeed, your phone. However, you will have much better chances of success and generate much more detailed pictures with a good interchangeable lens camera equipped with a macro lens. You can get excellent results with a standard lens and extension tubes or with an accessory lens, but you really cannot beat a macro lens for sharpness. I have three: an Olympus ED f2.8 60mm (for micro 4/3rds), an AF-S VR Micro-Nikkor 105mm f2.8G IF-ED (for Nikon SLRs), and a Loawa (Venus) 25mm f/2.8 2.5-5x. The latter is a specialist lens for extreme macro and the first two are fantastically sharp macro lenses for two different camera systems. Macro lenses also make excellent portrait lenses. For me, a key characteristic of a good macro camera is not how sophisticated its ‘bells and whistles’ are, but rather how it ‘handles’. Two aspects of handling are key: the system has to be light and it has to be easy to maneuver. It is true that you could take brilliant macro shots of plants or dead insects with a massive plate camera. However, an hour or two on a hot day hiking over rough ground kneeling, squatting and lying down, over-and-over again. and trying to maneuver your camera into position between grass stems, and you soon come to appreciate ‘small and light’. I love my Nikon and 105mm macro lens but that rig weighs nearly twice as much as my Olympus OM-D EM1 Mk2 with its comparatively tiny 60mm macro lens and thus I nearly always use the latter. The Loawa lens is a very specialized lens; a kind of zoom microscope, for use only on a stand of some kind – more of that in another post. I would add that I also find my Olympus 40-150mm f/2.8 Pro zoom useful because though it is not strictly a ‘macro’ lens (ie it doesn’t go to a 1:1 reproduction ratio) it is good for ~1:5, is unbelievably sharp for a zoom, and is great for larger objects.

Contradiction no 2. You need a tripod – you can take good shots handheld.

If it’s flighty insects you are interested in then I find a tripod next to useless and even a monopod is way to clumsy and hard to maneuver. There are occasions where a tripod can be useful, for example when ‘focus-stacking’ or taking HDR photos but mostly by the time you have it set up, the thing you are trying to have photographed will have long gone! A tripod can be of use when photographing plants or insects that remain motionless but even then, a camera with a good image stabilization system can make it a lot easier to clamber over a barbed wire fence! If you want the perfect shot of say an orchid, you can protect it from the wind with a ‘light tent’ and light it with the sun plus accessory flashes – you will get brilliant studio quality shots. If that’s what you want, then that is what you should do though 90% of the time you will do nearly as well with a handheld camera and daylight. On the whole, I believe in traveling with your camera and taking as little kit as possible. I will not mention it elsewhere but something that seriously transformed my experience of macro photography was to ditch the neck-strap that came with my camera. I swapped it for a ‘Peak Slide Lite’ strap. This allows for the camera to hang by my side, around my neck if I want (I don’t!), and for me to slide it rapidly into place in front of my eyes. Quick adjusters allow me to change instantly the height at which the camera hangs. Straps like the ones from Peak seem so expensive (£55!) – grin and bear it – they make a big difference.

At some point you will want a tripod. Get one that is light but as solid as possible, and that has a ‘beam arm’ that can be swung out at right angles to the tripod. It needs to be possible to set it really low to the ground as well as to use it more conventionally. Tripods are a very personal choice. Try to borrow some or watch other photographers wrestling with their octopuses! Mine seldom leaves home but I do use it. Monopods? Yes, maybe. I find I can use a hiking stick as a support – you hold the camera against the stick and slide the camera down to where you want it. You can buy monopods that are also hiking sticks. Bean-bags – why not? But I never use them.

In summary, if I had to say what was key to a stable camera in most of the situations in which I take macro shots, it’s a good image stabilization system and good camera holding technique (see below). The 5 axes IBIS system in the Olympus is fantastic and being part of the camera body, it works with all lenses.

Contradiction no 3. You can only get really sharp picture with a flash – you don’t need one.

Both are true. I mostly take three kinds of pictures, all handheld – without a flash, with a flash used as a fill-in light source, with a flash where I try to eliminate all natural light. On a bright day in the South of France with the ASA set to 200 you can take ‘sharp enough’ pictures without any kind of lighting other than the sun. Indeed, most of the pictures I take are taken that way. Pictures taken by natural light look err umm, ‘natural’. Anything they lack in ultimate sharpness is often only visible to ‘pixel peepers’ and you have the delight of traveling light and being instantly ready for a shot. I say traveling light because a naked speed-light mounted directly on the top of the camera is not the way to take good macro shots. To look even vaguely natural, the light from a flash needs to be diffused. The little pull-out or clip-on diffusers for a flash are handy but not very effective at their job. You need something much bigger – a proper macro soft-box. There are lots of suggestions for home-built soft boxes on the web. You can make a really effective one with cardboard, duct tape, and tracing- or tissue paper. A soft-box will provide the all light you need but because the light comes from the diffuser rather than directly from the flash head, harsh shadows and specular highlights are reduced. The result is a softer more natural looking photograph. With a big soft box it matters less where the flash is mounted, and though off camera would probably be better than on, the rig becomes harder to handle, so mine stays firmly on the hot-shoe. Ring flashes, dual macro flash etc. all have their place but frankly a manual flash with a soft-box is a cheap and effective solution in most situations. Fill-in flash lets you operate at the optimal f number and exposure time (see below) as well as filling in the shadows. As a result, the photos taken can be sharper than when using natural light alone.

Well, overkill? I 3D printed this softbox for my Nikon where it looks a little less out of place. However, it works really well on my much smaller Olympus m4/3rds camera.

There are occasions when you may want to eliminate nearly all natural light and depend solely on the light from a flash-tube. What follows is only relevant to that situation. If you want ultimately sharp photos then there is nothing to beat a flash gun with the intensity turned down. The duration of the light flash from a speed-light is related to the intensity of the flash. Elsewhere on this blog, you will find an article where I measure the duration of a flash from a speed-light. At full power my Yongnuo 560 III speed-lights have a flash duration of about 1/300th of a second. That is really slow. Why? Because when you have a tiny object in front of your macro lens even a slow movement translates into a fast movement in terms of the number of pixels the object moves across on the camera sensor. So for example, if an object contains features such as the hairs on an insect body that have dimensions of say 10um then at a 1:1 magnification, a movement at 1mm/s translates into a movement of 33um during a full-power flash. The pixel pitch on my Olympus camera is about 3.3um so instead of occupying ~3 pixels on the sensor an object on the scale above now appears on 10 of them – it has been badly blurred. 1mm/s is only 3.6m/hour which is nothing compared to wind-speeds, the movements insects make or indeed, the trembling hands of the would-be macro photographer! This is not to say that you cannot get a decent photograph with a 1/300th exposure but if you turn the flash intensity down to say 1/32nd of full power, the flash lasts only 1/13000th of a second, a duration that will freeze almost all motion. While we have a way of freezing motion, this will not make up for a lack of focus – that is a separate matter (see below) .

The front of my giant macro softbox. The area of the diffuser is huge by comparison to that of the front of the Yongnuo 560 III flash gun.

Someone reading this might ask why did I start out by saying you may want to eliminate all natural light? When you take a flash photograph the sync speed is generally 1/250th of a second or slower. So, if there is a lot of natural light reaching the sensor, this will produce an image that is superimposed on that produced by flash, the image from the flash may be sharp but that formed by natural light may for the reasons I describe above, be in a different position on the sensor, or otherwise blurred. Ways round the problem of blur caused by having both natural light and some light from a flash is to either use a tripod, or minimize and put up with the blur, or eliminate as much of one light source as you can. The object of the kind of macro photography I am discussing here is to make the light from the flash as predominate as possible. Paradoxically, when that is the object, areas of shade then become the best places to take pictures. If you can’t work in the shade you can try to use your shadow to block out the light from the sun or choose an overcast day.

So how do you use a flash to overwhelm natural light? The key is to set up the camera so that natural light forms little or nothing in the way of an image. This can be done by selecting a low ASA – I usually use something between 64 and 200 ASA. Adding a neutral density filter (ND10 is good) will in most situations reduce the natural light entering the camera at 1/250th of a second to very low levels. The flash employed needs to be of sufficient luminous intensity (high guide number) to generate an image when operating at relatively low power levels say, 1/8th to 1/64th of maximum power. This will ensure that the flashes are of very short duration. For the flash to be bright enough, you need to be relatively close to subject say, less than 0.5m. The quality of the photo will be best when a large soft-box is employed. Pictures taken this way can look dramatic and perhaps unnatural but will if the focus is good, be critically sharp. By using a flash diffuser and shooting in RAW so that you can bring up the background in post-processing, it is possible to produce tolerably natural looking and sharp photos. It also provides in combination with a suitable trigger (see past blog posts), a way of taking pictures of insects in flight. The photographers out there that enjoy ‘high-speed photography’ to take pictures of projectiles, smashing pumpkins etc., will recognize the similarity between the techniques they employ and those described here. One thing worth adding here is that while motion-induced blur may detract from the technical excellence of a photo, it may well add to its artistic impact.

One of the first photos I took using the technique described here of overwhelming the ambeint light with that from a flash. I also used a laser trigger (see earlier posts). The technique is particulary good for stopping motion.

Entire books could be written about macro flash photography using several speed-lights and a ‘macro-studio’ but that is a subject for another post.

Contradiction 3 – You need to use a very small aperture to ensure you get things in focus – you need to use a large aperture to ensure things are sharp. (Focus!).

Really, we need to think here about the whole subject of ‘getting things in focus’. Nothing is more important in macro photography than ‘focus’ even if you are aiming for an artistic result, you need to know what will and will not be, in focus. The reason that focus is so important is that when you are close up to an object the depth of field (dof) becomes very small. My 60mm macro lens focused on an object 30cm away and set at f/8.0 has a dof of 4.6mm. Move into the closest it will focus (19cm) and open it up to its maximum f number (f/2.8) and the dof is 0.6mm! Pick up a short pencil and point it at a nearby edge and watch the point of it moving about – natural tremor makes focusing at high magnifications while hand-holding a camera very challenging. It doesn’t matter if you employ the techniques above to freeze motion, hand tremor and the sheer physical difficulty of setting the lens to a perfect focus mean that while you may have a photograph with some part of the object of interest in focus, it may not be the ‘right ‘part. Anyway, what is the right part? Let’s answer that question first. Obviously, it’s the bit you wanted to be in focus which for an insect will usually be the compound eye. Other things may be a little fuzzy but it’s the eye that draws the eye! In many cases, no matter how stopped down the lens may be the available dof will mean only certain features can be in focus in a single image (see below re: stacking). So, without using a tripod, how do you ensure a good focus? You could stop the lens down to say f/22. For the closest focus of my 60mm macro lens this will increase the dof to 4.3mm but that will cause diffraction blur and worse still, unless the predominant light is from a flash, the increased exposure time necessary will mean camera shake may increase to unacceptable levels. What to do?

Different photographers have different way of holding a camera. My way is if I can, to choose kneeling, standing or lying down, over squatting. Stability of your body and arms is everything. I keep my arms tucked into my sides and hold my breath once I start to focus until after I have made the exposures. My right hand on the camera grip and my left on the focus barrel. My camera is always set to single AF plus manual with ‘back button focus’. ‘Back button focus’ means setting the camera so that a button on the back of the camera takes over from the shutter release button where focusing is concerned while the shutter button just err releases the shutter! Back button focus sound trivial but actually it is key to getting sharp photos – try it. I use a single small central focus point for the AF. Usually, particularly if I have set the focus limiter on the lens to a suitable range, but not always, the focus will lock. If it doesn’t I use the focus barrel to get into focus. It’s good to have a macro lens with a long ‘throw’ that is to say that a large movement of the focusing ring causes only a small change in the focal point. I find the whole process of focusing is much easier if you have a focus peaking setting on your camera. Focus peaking highlights in a colour of your choice, the pixels on the edges of objects that are in focus. It isn’t a ‘must have’ but it is extremely useful. I always have my camera set to use its electronic shutter so there is no noise or shutter shudder and minimal ‘shutter lag’ (the time it takes after pressing the release button for the camera to actually take the picture). My camera is set to manual exposure so generally, I will have already set the aperture and shutter speed as I want them using a nearby plant or bush to get things right. If the object is very difficult by which I mean the wind is blowing, or it is moving around, I may set the camera to rattle off quite frames a second. Sometimes I will also bracket the exposure in either speed or aperture. When taking either single or multiple frames, I use an almost imperceptible rocking of my body to achieve perfect focus before hitting the shutter button. Using your camera as a machine gun seems an attractive way to go until you have to sort through the pictures to find one, if any, that is sharp.

To go back to the contradiction of a large versus a small aperture, the truth is that these things are trade offs between the dof available at any particular aperture, the loss of resolution that results from diffraction when light passes through a narrow aperture and ‘artistic’ considerations such as the ‘bokeh’ (the blur of objects in the background).The optical testing of lenses using charts dominates magazine reviews but in fact the most important aspect of lenses is how they perform in the real world. I generally seek to use an aperture around the best for minimal diffraction and best optical performance (f/5.6 to f/8.0 for the Oly 60mm) but shift from this if ‘needs must’. I generally try to work with shutter speeds higher than 1/300th but sometimes again needs must. Similarly, I’ll work at low ASAs (200) to minimise noise but if trying to shoot a Humming Bird Hawkmoth, I’ll go to much higher ASAs to get say 1/8000th of a second exposures to freeze its motion. Bottom line, everything is a trade off but it is as well to understand the principles involved.

Contradiction 4. You can’t have everything in focus at once. (Stacking).

Well that isn’t altogether true. By using a focus slide or the ability of some cameras, to take a series of photographs at different planes of focus, it is possible to have much more in focus than would be possible in a single shot. You do not need a fancy camera to do focus stacking. It can be done with a simple mechanical device that allows the camera to be moved forward in steps in the same orientation, or by focusing the lens at different points in different exposures, or by using the ability of some camera to do the equivalent of these maneuvers using the focusing mechanisms internal to the camera’s lens. Focus stacking, no matter how it is done takes time and thus is not suitable for subjects that may move. The process generally requires the camera to be fixed on a tripod or other support. It is a powerful process and is capable of producing some great pictures. It requires post-processing software that can remove the out of focus information, align and combine the images taken. I may cover this in another post.

Photos taken using stacking can contain details over the depth within and image that could not possibly be encompassed within a single shot.
The detail that a macro lens can achieve with stacking is extraordinary.

Contradiction 5. You will get the best macro shots on a butterfly farm or with home-reared specimens – it’s better in the field. The same might be said of botanical specimens?

Both are true. You can be pretty sure that a day out at a butterfly farm will provide some fabulous opportunities for shots of exotic butterflies from far away countries – so why not? If you can get some butterfly pupae and have them emerge at home that too will provide some fantastic opportunities for macro shots that you would be very unlikely to be able to take in ‘the wild’. However, neither of those two options allow for the fun of ‘hunting’ with a camera. I am going to boast that I am quite a good hunter but…. I used to be hopeless. Now, I know my prey. I know when and where different butterflies, and other insects will appear, where they are likely to settle and be least disturbed by my presence. How to move to reduce the possibility that they will fly off. When to wait, and when to move. It’s good to have read about the habits of the things you seek to photograph and which habitats they prefer – see for example Thomas and Lewington’s wonderful book, “The Butterflies of Britain and Ireland’. You soon learn not to let your shadow fall over a butterfly – it will fly away, not to come between a butterfly and the sun, and to move slowly and wear subdued colours. When you look at a butterfly, you will see a dark spot in the centre of its eye. This is the ‘pseudopupil’ and it is the region of the eye that is directed towards the point from which the eye is being observed. When you can see the pseudopupil the butterfly can see you, the bigger it appears the better its ability to see you. Start by taking shots at a distance then move slowly towards an insect of interest taking more shots as you go. Always watch the histogram! Nothing will make a poorly exposed picture great though shooting in RAW will offer more post-processing opportunities to get things right.

Photos taken handheld and using natural light can be sharp too!
Ditto! Even indoors with the light from a window.

A PS…some other notes on the camera settings I use. You’ll find a lot of macro photographers who say you should use Aperture Priority (AP) – after all, what could be more important than what is and isn’t in focus? To my mind AP is great if the object isn’t going to move much but if it is, then Shutter Priority comes into its own because close-up even the tiniest movement of the object or your hand will cause significant blur, often setting a fast shutter speed is the key to a tack sharp photo. Full manual is the way to go if you want complete control but beware what I call the ‘time to flight’ factor – how long is that creature going to stay there? Quite often it’s a very short time indeed and for that, having everything set up so you can press the shutter button really fast is key. As a result, auto-iso and setting a minimum shutter speed of say 1/350th or 1/500th with Single or Continuous AF plus manual will get you a shot you would otherwise miss – insects don’t wait to have their pictures taken!

About petermobbs

A tinkerer and maker of 'things' who loves macrophotography and the natural world. Retired scientist and former Chair of Physiology, Dean of Preclinical Medicine and Dean of Life Sciences at UCL, now enjoying the beauty of the Gresigne in South West France
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3 Responses to More on ‘macro technique’

  1. MR ROBERT MARSHALL says:

    Fascinating article Peter. You are clearly an expert in these specialist techniques. Maybe you should consider preparing a proper tutorial lesson/course or instructional video?

    • petermobbs says:

      Sadly, I don’t think I am an ‘expert’. I am minded of a photographer in the ’70s who was asked what was the secret of his success. He responded, “I take a lot photos”. In my case, you should the failures!

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