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a lot of folks think that 'true' micro techniques to be a 1:1 reproduction of the photograph subject, i.e. the photograph captured on the sensor is the equivalent size as the actual object being photographed, which is different to close up methods. close up and close up methods is niche and not for everyone, however it is something all photographers should try at some time to see if it is their bag. In order to capture the 1:1 reproductions it is advisable to acquire specially created close upoptics, such as the Canon EF100m f/2.8 macro USM, although these are quite costly and many people are not prepared on coughing up a few hundred bucks (or dollars) to see if close up methods is for them. Fortunately, there is a more affordable substitute you can procure. For those wanting to try their hand at close up and macro photography a cheaper alternative is to use extension tubes which in a nut shell are empty plastic tubes that are placed between the optics and the digital camera body. auto focus close up tubes contain no optics whatsoever, and byincreasing the distance between the lens and the sensor the camera is forced to focus closer to the object, creating a micro and close up type effect. auto focus close up tubes can be used with all lenses, therefore they are suitable for all photographers. Most modern digital SLR camera lenses contain autofocus technology, which in order to work requires the electrical contacts on thelens to be in contact with the electrical contacts on the camera body, therefore placing an empty tube, i.e. the extension tube, between the lens and the body of the camera may create a problem with the autofocus system. Fortunately, some extension tubes, such as those made by Canon and Kenko, have got the electrical contacts to preserve the autofocus feature however some auto focus close up tubes do not. This is worth keeping in mind before purchasing some extension tubes, although if you are comfortable using manual focus using auto focus close up tubes with no electrical contacts should not present any problems. As you'd expect, the auto focus close up tubes using the electrical contacts that preserve autofocus are more expensive than those that do not. many photographers prefer to use manual focus when taking close up and macro shots because of the shallow depth of field. As well as autofocus most new day lenses allow the photographer to the aperture, and this is also achieved through the electrical contacts. Whilst a lot of photographers will be willing to lose the autofocus feature it is unlikely they will be prepared to lose the ability to change the aperture of the optics. with close up tubes that do not have the electrical contacts means the optics will be wide open which is likely to lead to an unacceptable depth of field and blurred images. Very few lenses are sharp when wide open therefore with close up tubes that do not allow the aperture to be varied means the optics will not be at its sharpest. When using extension tubes without the electrical contacts there is a way of fooling the camera in to retaining a selected aperture setting but this is fiddly and time consuming. The process involves putting the digital camera in to aperture priority mode and setting it to the required setting. By holding down the depth of field button, removing the optics and then inserting the auto focus close up tube before putting the optics back on, all whilst holding down the depth of field button, the digital camera will retain the aperture set. Sounds a bit of a pain right? Well, it is. As the process is so long winded and cumbersome there is the added problem theimage may be missed. For example, if the photo subject is a bug by the time the digital camera and close up tube has been set up the photo subject may well have crawled away or flown off, however you shouldn't have any problems if photographing still life, insects or flowers. Removing the lens time and time again to change the aperture setting increases the chance of dust and debris reaching the sensor, which may cause issues. In addition, the glass fitting is likely to get worn out quicker and there is an increased chance of damage to both the digital camera body and the lens, which could prove to be very costly. There are no arguments, close up tubes are a good way of getting in to the world of close up and micro photography, although it is unlikely you will get proper macro 1:1 reproduction. That said it is possible to make some awesome images using close up tubes and a normal lens. Because of the all the implications associated with auto focus close up tubes. For some essential close up techniques tips click here
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