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Equipment for Dragonfly Photography
Anyone interested in attempting to photograph Dragonflies or other small subjects such as butterflies and flowers may wish to know something about the equipment needed to achieve the best results in this specialist area. Although many of today's compact cameras have a so-called 'macro-mode' they are not really suitable for anything more than the occasional shot of one of the larger insects. What's really needed is something that will get you close enough to fill the frame with your subject - without getting too close to frighten it or to cast your own shadow over it. 35mm SLR CamerasThis is by far the best choice for film photography as there is a wide range of both equipment and film types for all subjects. There are both 'Autofocus' (with manual over-ride) and 'Manual Focus' systems from which to choose. Manual focus is the preferred mode to use at close range so either type of system should be fine. In SLR cameras the 'taking' lens is used to both view the image and take the photo. A mirror and prism system projects the image onto a focusing-screen in the viewfinder and the mirror flips up at the moment of exposure. Several of the 'big names,' who produce an extensive range of kit, make budget-priced cameras to start you off into their systems. These will often come complete with a zoom lens with a 'Focal Length' around 28mm wide angle to 90mm moderate telephoto with the closest focusing distance giving a reproduction ratio (on the film) of around 1:4, or ¼ life-size. This is more than adequate for full-length shots of the larger dragonflies but to get closer for head-only photos and good-sized images of the smaller damselflies a purpose-made 'Macro Lens' that focuses all the way from infinity down to either 1:2 (½ life-size) or 1:1 (life-size) will be high on most people's shopping list. The actual distance that you need to be from your subject to achieve 1:1 is determined by the focal length of the lens. Lenses can be grouped into three main focal-length ranges: 50mm to 60mm The lenses get more expensive as you go up in focal length so it's worth considering carefully what you'll need to work comfortably in the field. Here are some typical 'closest focus' distances for a few lenses giving life-size reproduction: 50mm (Sigma EX lens): 18.8cm In each case the distance is from the subject to the film, not the front of the lens. As the focusing portion of the lens has to move forward by the same distance as its focal length to achieve 1:1 (see illustration) the front surfaces of the shorter lenses can get very close to the subject! Of course, there would need to be a larger amount of movement on the longest lenses so these are often of the 'internal-focusing' type where the lens stays the same length, externally, throughout. The price you pay for this convenience is a reduction in apparent focal length as you focus closer. This is caused by the movement of the elements within the lens having a kind of 'zoom-lens' effect and explains why, for instance, the 1:1 distance of a 200mm lens is not four times that of a 50mm lens.
All very technical, no doubt, and it's fair to say that many people go for the middle option of a lens from the 90mm to 105mm group, often from one of the independent lens-makers. Some of these can be of similar quality to the camera-makers' own lenses but at much less cost. However, they can still set you back about £300 so it's worth considering a couple of cheaper options that will reduce the focusing distance of non-macro lenses. 'Close-up' lenses look like filters and screw onto the 'filter-ring' of any lens and as well as being available in different screw-thread sizes they also come in different 'strengths.' Basically, they bring the distant focus point of the lens (the 'infinity' position) much closer, say 40cms, and then the focusing ring of the lens brings you in closer still. 'Extension tubes' achieve a similar effect by fitting between the lens and the camera body. They often come in sets of two or three tubes of varying lengths to be used singly or in combination and, again, the longer the focal length of the lens, the more extension you will need to get into the macro area. With both of the above two devices you will lose the convenience of continuous focusing from infinity down to close-focus and there may also be a drop in quality. Using the lens at its 'best' aperture setting can minimize this - usually about three 'stops' down from maximum aperture. Some lenses, such as zooms and internal-focusing optics, don't perform so well with extension tubes as conventional 'prime' lenses of a fixed focal length. The quality of today's 'faster' colour print films such as 400 ISO and the fact that much of the time you will be shooting in bright conditions means that you may never need to use flash-guns or tripods when out in the field. This is all to the good as the simpler you can make the equipment side of the process, the more you can concentrate on getting that 'prize-winning' shot! Digital Still CamerasDigital SLR cameras with interchangeable lenses similar to 35mm SLRs are available, but with four-figure prices they are, perhaps, out of most people's range - at the moment! There is, however, a wide range of cameras available with fixed lenses that are very suitable for dragonfly photography. Some look similar to 35mm 'bridge' cameras (i.e. SLRs but with a non-interchangeable lens) whilst many are more akin to your average 35mm compact. Several are very definitely 'fashion statements!' Most will have far more features than even the best-specified 35mm compact cameras. The most obvious extra feature is the LCD screen on the camera-back, which gives a kind of SLR-type viewing. This is the vital key for using the Macro-mode that will usually be much better than any 35mm compact. The zoom lens can be anything from 2x up to 10x depending on the model and as the focal lengths are much shorter than film cameras they are often quoted with their '35mm-equivalent' for comparison. Very often the short end of the zoom range will focus closer than the longer end so you won't necessarily get a bigger image at the telephoto setting. However, you may feel more comfortable working with the telephoto end, as the closest focus may be too close at the short end. Digital cameras store the photos on removable memory cards - there are several different types: Compact Flash, Smartmedia, Memory Stick, SD, MMC, XD, Microdrive and only time will tell which is the most durable. They are available in various storage capacities from 8Megabytes (Mb) up to at least 128Mb with some as high as 1 Gigabyte (Gb). Higher capacities are promised in the future but not all of today's camera models will necessarily be compatible with them. The number of shots that can be stored on any particular card is dependant on the 'resolution' of the camera and the amount of 'compression' used in the 'JPEG' format. 'Uncompressed' images can also be stored on many cameras in 'TIFF' mode. Although these are the finest quality possible with your camera, the larger file sizes can be inconvenient, so for practical purposes most people generally use the highest camera resolution but in the finest JPEG mode. Once your best images are transferred to a computer or written to a CD-R they can be deleted from the card, which can then be used over and over again.
The reproduction ratios of 35mm SLR lenses, as quoted earlier, are fairly unambiguous - 1:1 life size is exactly what it says it is, on the film. So an item 20mm long can be measured as 20mm on the negative, but camera makers tend to be a bit shy about quoting macro ratios on digital cameras, listing only the closest focusing distances. When a digital photo is taken, or 'captured' and stored on the memory card or a computer it doesn't have any physical size to measure until you come to make a print of it so I suppose it all depends on how large that print can go before the image quality drops to an unacceptable level. Obviously, you can also apply the same principal to a 35mm negative. All other things being equal (!), the size of a camera's sensor will limit the amount of enlargement possible. The figures quoted for camera 'CCD'-sensors are usually in 'Megapixels' i.e. "Million 'Picture-elements'" so a sensor with 1,000 pixels across by 1,000 pixels down would be '1 Megapixels' or 1Mp. If you have a photo-quality inkjet printer, the finest quality can usually be achieved by sending the image from the computer to it at an 'un-resampled' resolution of 300 pixels per inch (300ppi) - whatever dots-per-inch your printer has. In many cases 250ppi or even 200ppi will be more than satisfactory so we can at last make some practical sense of all those figures. By looking at the sensor's pixel dimensions we can see what is available for us to print - so a camera resolution of, say 1800pixels x 1200pixels when divided by 300 will give a print size of 6" x 4" at the highest quality or 9" x 6" at the satisfactory resolution of 200ppi from which you can 'crop' the middle 6" x 4," if you wish, to keep a 'standard' print size. A 4Mp camera will fill a sheet of A4 paper at about 200ppi and will give about 65 - 70 'finest' JPEGs on a 128Mb memory card. If your chosen camera doesn't quite give enough magnification for the smaller damselflies then it may be possible to fit 'close-up' lenses similar to those described in the 35mm SLR section - if there is no 'filter-thread' on the front of the lens then adaptors are often available which will also accommodate other accessories such as wide-angle or telephoto-converters. Close-up lenses may, again, give a somewhat degraded image so 'stopping-down' the lens aperture by two or three stops will improve the quality whilst also increasing 'depth of field' - the amount of the image in 'sharp-focus.' At all times, each 'stop-down' of the lens by one stop requires a one-stop slower shutter speed to compensate for the reduced level of light transmitted through the lens. Keep an eye on the shutter speeds to avoid getting 'camera-shake' with too slow a speed. In bright sunshine the LCD screen may be difficult to see so some kind of sun-shield is highly desirable. There are several types available including ones with a magnifying lens built-in or you can make your own by cutting down a cheap hand-held 'slide-viewer.' The image quality from the best of today's cameras is very good but one area where improvements could be made is in the actual time needed to take a shot. There is a slight but noticeable delay in the LCD screen 'refresh' rate - move the camera and the screen will follow about ½ second later! There is also a delay from the time you press the shutter to the actual moment of exposure - the so-called 'shutter-lag' - whilst the camera checks focus, exposure and gives you a preview of your image. You also get a frozen image of your shot whilst there is another delay as the image is 'saved' on the memory card. All of this means you will evolve your own method of working which may be slightly different to a 35mm SLR camera. If you're waiting to see how the market develops before buying a digital camera it may well be worth looking closely at how the 'speed' of the camera is being improved rather than any big increases in the image-resolution size. Another very important area involving speed of operation concerns the ease of access to some of the camera's functions. There will probably be some 'default' settings that start the camera off in fully automatic mode ready for any quick shots but for something like dragonfly-photography you will no doubt want to use your own preferred settings. Buttons or switches on the camera body are usually accessed fairly quickly but some functions are only enabled by scrolling down the 'menu' on the LCD screen and this can be quite a slow process. So, even if you are drooling over the many features that the salesman is impressing you with, take time to check carefully how easily you can get at functions such as 'Manual Focus,' 'Aperture-priority Exposure,' 'Exposure-compensation,' etc. More importantly, check whether these settings are 'saved,' if you switch the camera off then on again, rather than reverting to the 'default' settings. Some cameras will have a 'custom' function where you can save all the settings you require for a particular task. If the 'wonder-machine' that you're considering doesn't comply with any of the above criteria then reject it because it will only cause you endless frustration when out in the field! Digital Video CamcorderModern digital camcorders have revolutionised home movie-making, giving much better quality than average camcorders of various analogue formats, in a much smaller package. It's also possible to obtain 'digital-stills' from them by various methods. Of course, their main function is to record the moving image and many people will buy one just for recording the usual family occasions without fully realising their versatility. As well as being a camcorder, many fully-specified models are also high-quality VCRs, basic stereo sound-recorders and digital still cameras. There will also be the full range of 'extra' features from 'title-generating' to 'night-shot mode,' etc. Shooting video of flying dragonflies is not easy - as well as trying to keep them 'in frame,' the auto-focus on most models will not be fast enough to keep up with a fast-moving subject! Manual focus over-ride is probably the best method to try but be prepared for a lot of wasted 'footage!' For taking still shots of any subject there are two main routes to take - a 'video-grab' from a section of video, or a still photo on those models that have a slot for a memory-card. Those with this feature will usually let you do a video-grab 'in-camera' by just pressing the shutter-button whilst viewing the tape. For models without a still-shot function, and to select the precise moment by viewing the tape frame by frame, the tape will need to be transferred to the computer. Many video-editing software packages will come complete with a 'Firewire' card, which will be necessary to handle the amount of digital information coming in from the camcorder. On a PC, you will also need Windows 98SE, at least, and you may have to alter some of the Windows 'default' settings - what fun! Even basic programmes should have a frame-grabbing function so you won't have to spend a fortune - unless you want to get into complex video-editing!
The image-resolution on those models with a still-shot facility will range from a basic 640x480 VGA up to about 2 Megapixels on some of the better models. A 1 Mp. model will give a print size of about 6"x4" (the proportions will be slightly different) at nearly 200 pixels per inch from the full frame size. This is probably the lowest resolution to consider for 'real' photo-quality. To avoid lower resolution images looking 'pixelated' the file-size has to be increased by 'interpolation' in a computer programme whereby extra pixels are 'invented' between those already in the image. Although this reduces the pixelation, the image can look 'soft' and lacking in detail - go for the highest resolution model that you can afford. Whilst only a few still cameras will have a long zoom range, many camcorders have a 10x zoom, at least. The telephoto end will often be equivalent to around 300mm to 400mm in 35mm terms. This makes them very suitable for shooting subjects from a more comfortable range and if the autofocus fails to lock-on it's a simple matter to switch to manual focus. As with digital still cameras, the closest focus point will probably be farther away at the telephoto end of the zoom than the wide-angle end and again, at this short end of the zoom the closest focus may be too close to use in the field. Anyone with a good quality bird-watching telescope may wish to try 'digi-scoping' with either a still or video digital camera. A number of shots that have appeared on this website have been taken this way. Whichever format one chooses, as well as buying the best quality one can afford, the most important thing is to obtain equipment that is easy and comfortable to use in the field. There's no point in owning something that's so heavy or awkward to use that it stays behind, at home! Of course, no single item will be ideal in every situation - it's just a matter of picking the best equipment for one's own needs. Incidentally, when I was confronted with the 'Mystery Italian Dragonfly' that appears on the Articles page, I had all three types of equipment with me and I went, almost unhesitatingly, for the 35mm camera - whether this was because I instinctively thought it was the easiest to use or because I didn't need the 'instant' digital image for sending to the 'News' page, I'm not 100% sure! |
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