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In March 2003, I began researching Macro work at extreme magnification. I found several articles on the internet, some very enlightening and others having little matter of fact. There are various methods used to achieve extreme magnification. High end macro lenses with extension tubes or bellows, and stacked diopters are just a few of the tools available to magnify and capture subjects just viewable at the very ending limit of our vision. There is also the reversed lens technique which has been used by photographers for many years with film based cameras, and currently being used successfully in digital work. In my estimation, it is probably the least expensive, with excellent results, and most challenging.
Film based camera lenses can be used as quality magnifiers for digital camera lenses. This magnification property can be seen by viewing an object through the end of a lens normally closest to the subject toward the film plane end of the lens. You will also notice an extremely narrow depth of field while trying to focus the hand held lens. The degree of magnification is dependent upon two factors. First, the prime lens which is on the camera, and second, the reversed lens. If the prime lens of a digital camera at maximum digital zoom is assumed to be at 150mm, and the reversed lens is a fixed 50mm then 150mm/50mm = magnification +3. For additional magnification a teleconverter such as the Nikon TC-E2 may be added to the prime lens before adding the reversed lens. For more in depth information regarding magnification of reversed lenses and teleconverters, please visit a most informative web page by Dr. Ching-Kuang Shene of Michigan Tech. Dr. Shene has also published several in depth pages regarding the Nikon line of digital cameras and accessories. Please click on the image below for visual information about assembling the reversed lens to the prime lens.
These small parts may be purchased from B & H Photo for about $8.00 each plus shipping. If they are out of stock, get creative and figure out another combination. If you already own a standard lens in the 50mm range, then the first step toward making macro images is almost complete. Can you use a larger or slightly smaller lens? The answer is yes of course, resulting in a change in magnification.
One of the major problems encountered when using reversed lenses for imaging is D.O.F. (depth of field). If you have already viewed an object through the reversed lens, then you have already experienced the difficulty in focusing upon a subject. In most imaging situations, unless the subject size is slightly smaller than the Depth Of Field, part of the subject will be out of focus.
Another problem you will encounter with reversed lens photography is the gathering of light through the reversed lens. The lens used in the previous photo is at it's largest aperture opening of F3.5. Even though it is usable and has produced some quality images, good exposure with this lens is difficult. Ideally, you would want to use a lens with a maximum aperture of F1.2 or 1.4. The closer the lens is moved to the subject, the less light you will have for viewing and exposure. While adding additional magnifiers to your prime lens, such as Diopters, and Teleconverters to provide larger images, focusing will become even more problematic, as hand held imaging becomes more difficult. All Focusing is done by moving the camera physically toward and away from the subject.
Nikon E995 Digital Camera with Prime and Reversed Lens settings: The optimal settings used most of the time for the equipment that I am currently using is as follows: 1. Reversed 50mm Nikkor 1.4 lens = Aperture F1.4 - Focus at Infinity 2 Nikon E995 digital camera = Full Manual Mode, Aperture F7.9 - F10.3, Focus set to Manual at Infinity. Shutter Speed 1/250th or 1/125th. (These settings are only valid with the external SB-18 flash turned On)
Bounced Fill Flash and Controlling Light: The above settings are used in conjunction with a bounced fill flash from an Nikon SB-18 speed light which is synched with the camera. I set the External flash to Automatic, and Internal Flash to Off. It is a rare occasion, or very sunny day, when the sensor shuts the external flash off. The basic exposure technique in the above photo has been used for decades by photographers, particularly in studio work. It is simple, inexpensive and it works well. When the reflector gets damaged just throw it away and cut out another. If you leave the reflector at home, stop off at Dunkin' Donut, pick up a dozen donuts, and use the lid off the box. I would also like to mention Color Cast Problems which are curable in Photoshop, but time consuming. Prevention is the best solution. I find that the colorcast usually occurs when foliage gets between the Fill flash system and the lens. The light seems to acquire the properties from whatever object through which it passes. The nature of this setup is that it is a bit bulky to be poking into bushes in pursuit of insects, hence some missed imaging opportunities.
The Velbon macro slider is moderate priced and is able to transport the entire setup forward approximately 2 1/2" inches from its home position. It also is capable of movement from left to right. Tripod support is a Benbo Trekker with swivel ball mount. This tripod is ideal for all of the manipulating that has to be done for subject positioning. There are nine combined adjustments available that can be made for fine tuning light exposure, and image composition. Six adjustments can be made to the tripod, two on the slider, and one on the Speed Light.
Until March 2003, I had no idea that I would be trying to photograph a Fly or an Ant. I had just broken my left arm, and was looking for something to keep me occupied until I fully recovered, which I have. Like many others, I had no appeal for insects, especially flies. So, what is the big attraction for taking pictures of bugs? For me it began with the challenge. Trying to poke a lens in a fly's face at two inches without it flying away. Lesson number one is that it requires patience. Flies don't like shadows or fast movements. Some species have sat in front of the lens for as long as twenty minutes with very little activity. Others, will groom themselves, or blow bubbles. Yet others jump onto the lens. The fact is that they are never seen in detail, they are always flying or just a spec on a wall.
Good Luck Hunting and satisfying your curiosity. Richard Flake
Copyright © 2000 – 2010 Richard Flake All Rights Reserved
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