ADELAIDE HILLS PHOTOGRAPHY CLUB COFFEE BREAK 22 APRIL 2015 MACRO PHOTOGRAPHY

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1 ADELAIDE HILLS PHOTOGRAPHY CLUB COFFEE BREAK 22 APRIL 2015 MACRO PHOTOGRAPHY WHAT IS MACRO? Depends on who you talk to. Most definitions regard macro as meaning life size on your image sensor. So, on a 35mm (full frame) camera, a 35mm wide object would appear as a macro image in clear focus and occupying the full 35mm of the frame. For a smaller format camera, say with APSC sensor, that would mean an image of a 24mm object occupying the full frame. And so on for other size sensors. Photographing objects that are smaller than this is sometimes referred to as micro photography. For the purpose of this session, let's stick with something much simpler. Let's say it just means photographing small objects very close up. WHAT YOU NEED Essential Camera Digital SLR or mirrorless camera with close focussing lens (ideally, but not essentially a dedicated macro lens) Bridge camera with a macro button on it Point and shoot camera with a macro button on it Desirable You can take perfectly good macro shots with a point and click or a bridge camera using just the macro button. For DLSR and mirrorless cameras you can get there by using a minimum focal length and cropping your shot. If you want to go further with macro photography, you can think about the items on the following list. Flash/es (one or more camera mounted or with brackets to hold them; maybe a ring flash for DSLRs/mirrorless) Mounts for flash/es - whether on or off camera Tissue paper or other light diffusing material to soften the flash Light reflector to bounce light on to subject - can be home made from crumpled aluminium foil, even white paper on cardboard White light LED torch Something to steady your camera Ideally a tripod, but could be a gorilla tripod (bendable legs) or a monopod A bean bag For SLR users, extension tubes will enable much closer focussing of any lens you may use, but at the expense of an F-stop or two of light. For particularly keen SLR users, bellows (rather like extension tubes of variable length). For all types of cameras, but particularly for SLR users, focussing rails will enable very precise focussing. Usually this will also involve the use of focus stacking in post processing - this entails multiple images of your subject, each moving the focal point by a millimetre or a fraction of a millimetre. Focus stacking works most accurately by having the front of the lens fixed to the rail, and for the camera to move behind it using bellows. Depending on what you want to photograph (e.g. indoors/outdoors), some fabric in the colour of your choosing against which to photograph your subject. This could be objects arranged on the fabric, or where the fabric is held by an obliging assistant to form a background to your subject where the background would otherwise be distracting. If you plan to be photographing in the field, you may want to consider using a ground sheet.

2 DEPTH OF FIELD ('DOF') This is the single biggest challenge in macro photography. Without going in to all the technical reasons, let's just say that when you are trying to focus on an object that is very close to the camera, the closer you get, the shallower the depth of field is going to be. This means that only a very small part of your image will be in focus. This happens with all types of camera, but is probably most noticeable with the higher quality, specific macro lenses, and even more so when using extension tubes (or bellows). 2 Methods of dealing with DOF issues Since you will experience DOF issues in the same way as you do with wide apertures, only more so, you can start by trying to deal with it in the same way, namely by closing up the aperture. Don't try to take your macro images at F2.8, but see if you can do so at F16. This introduces a new problem. Remember that your image is produced by light that falls on an image sensor. The smaller your aperture, the less the light that falls on the sensor. You can try to overcome this in 2 ways: You can let the light in for a longer time. This is fine if you have subjects that are not going to move, and can be done easily enough for indoor shots. Which is why it will be very important to use techniques like tripods, bean bags and remote release shutter control (and mirror lock up with SLR cameras) to avoid camera shake. This is not always so easy when trying to photograph moving subjects such as bees, dragon flies and flowers in the wind. Which is why you often see photographs of insects with frost on them as they start to thaw out in the early dawn on a crisp winter morning, since the insects haven't yet started moving, and in these conditions there is no wind. This allows for more a longer exposure, with more light falling on the sensor without your subject having moved during the exposure. You can find ways of getting more light on your subject, which will allow you to use a smaller aperture and increase the DOF. Reflectors will allow a certain amount of additional light to fall on your subject. and can help. Reflectors can be bought from photographic shops and ebay. You can use cardboard covered with crumpled and semi-straightened aluminium foil or even light coloured paper. For indoor shots, you can use studio lighting. This can be incandescent or fluorescent lighting, or specific studio lighting for those who want to go to this extent. Remember to check that you have your white balance set for any such lighting, particularly if you are not shooting in RAW (where you can make any necessary corrections in a program such as Photoshop). For more dramatic increases in light falling on your subject, you can use on or off camera flash/es. This can be on or off camera. On camera flashes can be mounted: o Most cameras have a small(ish) in-built flash, often a pop up device that will add some additional light. Issues can arise with these flashes, particularly when photographing maco subjects, because of shadows thrown by the camera lens or simply because part of the subject will have a shadow cast over it. Sometimes you can deal with this issue (at least to a limited extent) by a sheet of tissue paper over the flash to diffuse the light. o On the camera hot shoe (where equipped). This allows for stronger flash units to be used, but this may require additional measures to diffuse the light. You can try pointing the flash in a different direction to achieve a bounce effect, maybe in conjunction with reflectors, using tissue paper or the diffusers often supplied with flashes, or soft boxes etc.

3 3 o o On a bracket attached to the camera. I have used a bracket with one large flash mounted on the hot shoe as the master unit, and 2 slave flashes mounted on a bracket to the left and right of the lens. This introduces a massive amount of additional light, from three sources, which goes a long way towards eliminating shadows. This technique can be used even in bright sunlight, and in situations where your subject might otherwise be silhouetted. It can also mean that even brightly lit distractions in the background are significantly darkened out. But care still needs to be taken to ensure that the light falling on the subject is not so harsh as to cause burning out of areas of the subject. This leads back to techniques such as flash bouncing and reflectors. There is no single, easy, one size fits all answer for dealing with all issues that can arise. Ring flashes are often used in scientific photography of macro subjects. These flashes can operate in conjunction with the camera's own flash system, and introduce a uniform light on the subject from a ring formed around the front of the lens. They have the advantage of being very close to the subject, and not needing to produce a massive amount of light, since they are so close to the subject. They also produce a very uniform light, and therefore don't tend to throw shadows. The downside, however, is that they throw a very flat light, and many photographers avoid them for this reason. Off camera flashes can be set up, whether in the studio or in the field, for dramatic back or side lighting to provide interesting effect to your shots. Usually these flashes will be operated by a remote control from your camera, or as a slave to the flash that pops up from your camera, or to a flash that is mounted on the hot shoe of your camera. Included in your list of desirable objects is the white light LED torch. These can be very useful at night. If you have a subject remaining very still on a windless night, e.g. a spider sitting very still in a web, you can sometimes get very lucky with a long exposure lit only by an LED torch. When doing this, remember to move your light around your subject to avoid any overly light or dark patches - this is sometimes called light painting. Or, if you don't have the level of patience for this approach, you can at least use your LED torch to illuminate your subject whilst you set up your tripod and flash/es and get your focus perfect before absolutely smothering your subject with a massive burst of flash. A final method of dealing with the DOF issue is focus stacking. This entails the use of focussing rails to allow the taking of multiple images, each advancing the focus incrementally. It is common to focus stack 3 to 6 images. In one book that I have seen there are images in which 300 images have been combined to produce a sharp focus over an image that is only a few millimetres in size. This is its own specialty, and not one that I have practised.

4 4 SETTING YOUR CAMERA FOR MACRO You need to consider focussing methods. Often when using the camera hand held in the field (i.e. not on a tripod) I will use manual focus. This technique works for SLR and advanced compact or bridge cameras, where you see in your viewfinder exactly what is happening on the sensor. I haven't tried it with a mirrorless camera, but it should work if what you see in your viewfinder is the same as what is happening on your sensor. I don't think it will work for point and shoot cameras where the viewfinder does not capture exactly what is happening on the sensor. My technique involves setting the focus manually (usually one or two buttons on the camera and/or lens on an SLR, and most compact, mirrorless and point and shoot cameras will have a single button). Then hold the camera on the subject, moving very carefully and slowly backwards and forwards until the focus on your subject is as clear as you can get it, then capturing the shot. The advantage of this method is that it eliminates any potential for the camera to find a focus point other than exactly what you want, or for it to determine that it won't take the shot because it doesn't agree with your idea of good focus. I don't always use this method - it depends on how I am going on the day, and particularly if I experience any frustration with auto focus. It's something to bear in mind, and maybe have a go at if you would like to try it. If you want to go with auto focus, then you need to consider what method of auto focus you want to use. For macro work, I find that you want to focus on a particular subject, and often part of that subject due to the DOF issue. For this reason, my preference in auto focus is to use spot focussing. You can set this by accessing the menus of your SLR, mirrorless, compact or point and shoot camera, and making this selection. You should then see in your viewfinder a point of focus that will let you know what the camera is selecting as its focus point, and this will give you the most reliable focus. The next most reliable method is centre weighted, or smaller centre area (depends on camera brand and selection offered in your menu). This allows you to choose a smaller area in the centre of your viewfinder, which is not as small as spot focussing, but not as large as a multi zone, or overall/evaluative focus. These latter methods will give you unreliable focus on a macro subject, and I do not use them. Set your camera to macro mode (where available). This will be available on most compact/bridge and point and shoot cameras, and is most commonly shown by shown by a tulip icon. Pressing this button changes the camera to a short focussing mode, and enables close up photography. I don't have experience of mirrorless cameras, and don't know whether these cameras have a macro button. Most SLR cameras don't have a macro mode, as the focussing method is a peculiarity of the lens rather than the camera. Where you have a lens that has a macro setting available, it should have its switch or focussing method changed on the lens to enable close up focussing. Where you can do so, set your camera to Aperture Priority in order to gain control over your aperture, and give yourself the best chance of dealing with DOF issues. Depending on your brand of camera, this may be shown as 'A' or 'AV' or whatever else the manufacturer decides to label it. But you need to be able to set the aperture to as large a number (which is as small an aperture) as you can manage.

5 5 Set your aperture (if available to do so on your camera). I have found F16 to be a pretty good starting point to achieve the best DOF. Set your white balance for the lighting conditions you are using - particularly important if you are indoors under incandescent or fluorescent lighting, and even more important if you are shooting JPEGs rather than RAW. (You can at least correct RAW images for white balance in Photoshop and similar editing programs. You have no such second chance if you are shooting JPEGs, as is the case with most point and shoot cameras.) Set your ISO sensitivity. Remember that you can shoot at faster speeds by using a higher ISO, but this may come at the expense of digital 'noise'. This is something that you will come to understand only be experience with your camera. Set up your tripod and flash, reflectors, or other lighting aids. Set up any backdrops that you may wish to use. Do some test shots to see how things are going, and review your images. This is best done on a computer screen, as I have been caught many times by reviewing and image in camera, even considerably enlarged in camera, where I have been fooled into thinking I have had a good image. If using flash, check whether you have burned out spots in your image. You may need to bounce your flash, or use some filtering or attenuation devices, or bring it down a level or two. Do any additional test shots you may need to get things right. Be brave - try some manual settings for aperture and exposure times, particularly where you are not shooting moving objects. I have had some success with a lot of flash on flying insects in daylight, with times set at 1/60 or 1/125. Review your histogram to check how you are going. You may just surprise yourself.