Macro

Macrophotography

People are always attracted to extreme close-up views of anything, especially where commonplace items are displayed in an unfamiliar perspective… such as a closeup of a leaf, fibers from a carpet, skin texture etc. This is because the human eye cannot focus closer than about 5-6 inches (125mm-150mm) without the use of optical aids. Close-up photography captures this amazing unseen world, and is endlessly fascinating. This is a world where one does not have to travel to exotic locations for subject material… it is all around us, and a few feet of backyard provides an infinite realm of photographic possibilities.

In normal photography, the standard 50mm lens has a minimum focusing distance of about 18 inches. With specialized accessories, or with a dedicated macro lens, this minimum focusing distance can be reduced to a few inches, with corresponding increase in the image size on the film. The easiest way to enlarge is by cropping, of course, where the area of interest is enlarged to the desired magnification. However, this range is very limited, and even with the best low grain slow film, enlargements will be blurred and grainy. This is a 35mm format issue, since the film size is so small.

Larger formats can be cropped and enlarged to a greater degree with little loss in resolution, provided a tripod and slow, fine grain film has been used. 1x or 1:1 magnification ratio means that the lens is capable of reproducing an image at full or life-size on the film. In the case of 35mm photography, the film dimension is 24mm x 36mm, with a diagonal of 43mm. In 35mm photography, this 24×36mm canvas is all that is available to the photographer, whether he or she chooses to photograph a vast landscape or a small flower. Let us consider an example… the US Quarter has a diameter of 1 inch (25.4 mm). If the coin were photographed at a 1:1 magnification by whatever means, it would not completely fit in the 24×35mm frame size since the frame is only 24mm on one side.

Remember, this is on the FILM. This will be a very high resolution image and actually printed on a standard post-card size 6×4 inch print (150mm x 100mm), the final image will be about 4x life size. There’s a lot of confusion and misconceptions when it comes to macro photography – the most basic being the question of “what is macro photography?” Lens manufacturers haven’t made it any easier, indiscriminately labeling all their close focusing lenses as “macro lenses”.

There are true macro lenses, of course, but these generally give a magnification of 1:2 or 1:1 (0.5x to 1x magnification). # Close-up Photography– up to 1:2 to 1:1 or 05x to 1x magnification (with close-up diopter lenses and extension tubes) # Macro Photography – 1:1 to 10:1 or 1x to 10x magnification (with extension tubes, macro lenses or bellows) # Photomicrography – greater than 10x magnification (with microscope and special adapter for the camera)

---

Close-up lenses
The cheapest way is to use simple screw in close-up lenses that are attached to the front of the lens just like filters. These close-up lenses are cheap and easy to use, and are supplied in a set of 3, with each having a specific strength in “diopters”, such as 1, 2 and 4. They can be used alone or combined for greater effect.
However, they have a very shallow depth of field, and most of the subject towards the edges will be blurred. Their ease of use and low cost makes them attractive, and they are sufficient for generalized use. The blurry nature of the images can be used to good advantage when photographing very small subjects like tiny insects, or flower stamens or lichens and moss, since the rest of the field other than the area of interest will be pleasantly out of focus. When combining close-up lenses, make sure the lens with the highest diopter value is closest to the lens.Hoya Close-up Supplementary lenses 52mm

caption picture URL

caption picture URL

caption picture URL

---

Extension Tubes
Extension tubes provide better results than the crew-in close-up lenses – they are simply hollow tubes on which a camera lens can be mounted, and come in sets of 3, with widths of 12mm, 24mm and 36mm (dimensions for Vivitar extension tubes – other manufacturers use other tube length combinations). With a 50mm lens mounted, they are capable of 1:1 or better magnification, however, stacking the tubes increases the lens distance from the film plane, and cuts the image forming light substantially, leading to long exposures. A tripod is recommended when anything more than a 36mm extension is used. The extension tubes I have are with an Olympus OM mount, and I can used the Bower adapter to mount them on the Sony Alpha 700. That gives me an additional 11mm (approx) extensionVivitar Extension Tube set

Vivitar Extension Tube Set

Vivitar Extension Tube Set

Vivitar Extension Tube Set

---

Bellows

Extension tubes are easy to use, and reasonably priced. However, the fixed width of the tube sections provides limited flexibility. The way around this is to mount the camera to a bellows, mounted on a rail unit with a mechanism for moving the lens and camera back and forth on the rails to adjust the focal length. Bellows extensions are usually about 150mm – 160mm in length, and can be infinitely variable within this range. Depending on the lens mounted on the bellows, different magnifications and working distances are possible.

Mounting a normal 50mm may provide 1x to 3x magnification, while a 35mm lens may provide greater magnification, but a closer working distance. 75mm and 150 mm lenses provide correspondingly greater working distances, but less magnification. It is possible to get dedicated flat-field “bellows” lenses of various focal lengths, but they are likely to be expensive.

Spiratone marketed an excellent series of dedicated (and reasonably priced) bellows lenses years ago. These include the tiny 35mm f/4, the 150mm f/4 and the 75mm f/3.5 flat field lens. They sometimes show up on eBay and almost impossible to get as a set.

Bellows and Bellows Lenses

Spiratone 35mm f/4 Macrotar

Spiratone 35mm f/4 Macrotar

Spiratone 35mm f/4 Macrotar

Spiratone 75mm f/3.5 Flat Field

Spiratone 75mm f/3.5 Flat Field

Spiratone 75mm f/3.5 Flat Field

Spiratone 150mm f/4 Macrotel

Spiratone 150mm f/4 Macrotel

Spiratone 150mm f/4 Macrotel

Spiratone Bellowscope

Spiratone Bellowscope

Spiratone Bellowscope

Spiratone Macrobel<picture

Spiratone Macrobel<picture

Spiratone Macrobel<picture

Macro lenses

Macro lenses are designed with a special floating element that permits the lens to be extended far beyond the range of the normal 50mm. They are designed to be very sharp at extremely close focusing distances, about 4- 6 inches. While they can be used as a normal lens, they may not be as sharp when focused at infinity.

Most of the OEM and Third party companies manufacture excellent dedicated macro lenses that can provide 1:1 magnification; however, these are likely to be expensive, especially if they are AF lenses. Sigma makes a beautiful 50mm f/2.8, expensive when compared to manual 1:1 lenses, but cheap when compared to the Canon, Nikon or Olympus 4/3 lens. In any case, it’s advisable to switch to manual mode when using a macro lens, since the AF mode will have the lens “hunting” like crazy.

They are great for general photography at normal distances. Among the manual macro lenses, the Olympus 50mm f/3.5 macro lens is designed to produce a 1:2 magnification an Olympus extension tube is needed to increase the magnification to 1:1. A couple of them are always on sale on eBay, but I’ve always felt that the high prices they go for aren’t justified for a macro lens that only goes to 1:2.

The Vivitar 55mm f/2.8 macro and Panagor 55mm f/2.8 are true 1:1 macro lenses and are simply magnificent. They are sometimes available on EBay for less than $50, and I’d advise anyone to grab one without a second thought. In the longer focal lengths, the Panagor 90mm f/2.8 1:1 Macro is a great buy. This lens is also a awesome portrait lens. As a macro lens, the 90mm focal length gives a better working distances as well, as compared to the 50-55mm range. Sigma, Tamron and Vivitar also make great longer focus macro lenses as well in the 90-105mm range. The Vivitar 90mm macro was made for them by Komine. It’s very similar to the Kino made Panagor 90mm.A special example of a macro lens system is a macro-teleconverter, which can provide a 1:1 magnification when fitted to a 50mm lens. In this case, the extension is built into the teleconverter, and converts the 50mm into a macro lens. Excellent examples of this type of teleconverter is the Vivitar 1:1 Macro Teleconverter and Panagor Macro Teleconverter, both made by Kino Precision.

Macro Lenses
These are my dedicated macro lenses on Minolta and Olympus mounts. I can use the Olympus mount lens on the Alpha 700 with the Bower Minolta AF-OM adapter.

Olympus mount Vivitar 55mm f/2.8 1:1 macro

Olympus OM mount Panagor 90mm f/2.8 1:1 macro

Minolta mount Sigma AF 50mm f/2.8 1:1 macro

Vivitar 55mm f/2.8 1:1 macro picture URL	Vivitar 55mm f/2.8 1:1 macro picture URL
Panagor 90mm f/2.8 1:1 macro picture URL	Panagor 90mm f/2.8 1:1 macro picture URL
Sigma AF 50mm f/2.8 1:1 macro picture URL	Sigma AF 50mm f/2.8 1:1 macro picture URL

caption picture URL	caption picture URL
caption picture URL	caption picture URL
caption picture URL	caption picture URL

---

text and images © 2007 ajoy muralidhar. all names, websites, brands and technical data referenced are the copyright or trademark of their respective owners.