Telephoto macro lens
About telephoto macro lens
Did you know that the average animal is the size of an ant? With statistics like this, it is no wonder why a major tool in the arsenal of a biological photographer is the macro lens. This section will tell you how to use a macro lens to its best effect.
Macro photography is usually defined as the realm where images are at least 1/3 life size or larger. Many telephoto, telephoto zooms, and "normal" telephoto lenses may be marked "macro" and will get you to the edge of this range. True macro, however, is usually done with a specialized macro lens and accessories. For more about macro lenses
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Macro requires some different techniques as opposed to wide-angle or telephoto photography. In particular, you need to concentrate on focus, camera stability, lighting, subject movement, and depth of field. Finally, we will touch on ways to use wide-angle and telephoto lenses with extension tubes to get macro shots.
Focus is critical in macro work. All too often, unfortunately, autofocus will not work with macro subjects, so you need to be prepared to focus manually. Whether focusing manually or automatically, keep these things in mind:
- With depth of field minimal, selecting the most important part of the subject to focus on is vital.
- If autofocus fails, it may be easier to set the camera to the magnification level you want and focus by moving the whole camera assembly towards or away from the subject.
- A focusing rail is very useful when the camera is mounted on a tripod. It allows you to focus by moving the camera in a very controlled way.
- If the subject, its perch, or you are moving at all, you might want to use a dynamic autofocusing mode. In these modes, the camera continually adjusts the focus right up to the point where the picture is taken (as opposed to a "one-shot" autofocus that focuses and locks in at that point before the shutter is released).
Whats the difference between a macro lens and a telephoto lens?
In macro photography, camera stability is more important the closer you get (the higher the magnification). More to the point, while camera stability is important, it is also harder to achieve unless your subject is motionless on a large, unmoving object like the ground or a solid tree trunk. If your subject is immobile, set up a tripod and do it right. If your subject is moving around, camera stability is the least of your worries - go handheld.
Lighting
The best pictures are those lit by natural light. However, in macro work it is not always possible to get enough natural light on a subject. This is often further complicated by the fact that working distances are small, and either you or your camera may cast a shadow on the subject. When using natural light, simply be careful about where your shadow is falling.
Flash is one obvious solution to the problem. The good news is that the short working distance means your flash will be able to put a lot of light on the subject. The bad news is that many on-camera or shoe-mounted flash units either can't put light right in front of the lens, or the lens itself will shade the flash. Also, bright flash at close range can overpower a subject, particularly subjects that are highly reflective. The solutions lie in the equipment:
1. Specially designed ring flashes put the flash in the right position.
2. A cord that allows you to move the flash off the hot shoe will allow you to position it for macro use (assuming you have a third arm).
3. Covering the flash with a softbox (or even a layer of tissue) can soften the flash.
4. Some flashes can be controlled; if the flash is overpowering, turn it down.
In recent years, the term macro has been used in marketing material to mean being able to focus on a subject close enough so that when a regular 4×6 inch (102×152 mm) print is made, the image is life-size or larger. This requires a magnification ratio of only approximately 1:4, more easily attainable by lens makers.
Subject Movement This is difficult to deal with. Whether it is insects moving on a flower or a flower blowing in the breeze, or an insect moving on a flower blowing in the breeze, subject movement is a nightmare for the macro photographer. Forget the tripod, go handheld. Some tips will help:
For plants moving in the wind:
- Use your body to block the breeze.
- Look for sunny areas at a forest edge or near a building or the base of a hill where the wind is blocked.
- Early mornings are often calm, and the light is good.
- Shoot during lulls in the breeze.
- Listen for breezes rustling nearby trees and be sure to get your shot before the wind gets to you.
- Find the sturdiest plants.
- Get down low to the ground.
- Brace the plant stem against the tripod leg or another plant.
- Hold the stem with a free hand.
- Use a continual, predictive, or dynamic autofocus instead of "1-shot" autofocus.
For moving animals (insects):
- Try to anticipate where they are moving to and focus there.
- Catch the insect and chill it in a cooler.
- Photograph on cool sunny mornings before the insects are warmed up.
- Stake out a location that attracts insects - if you miss one, another will be by.
- Use a continual, predictive, or dynamic autofocus instead of "1-shot" autofocus
True Macro Lens:
This is a dedicated 1:1 macro lens that does not require any special attachment to achieve true macro magnification, although you could “kick it up a notch” with accessories like extension tubes and/or close-up filters. These lenses are “prime” lenses, meaning that they are of a fixed focal length, usually in 50mm, 100mm, or 180mm. Just about every 35mm lens manufacturer, including Canon, Nikon, Minolta, Sigma, and Tamron, among others, produces true macro lenses.
Extension Tubes:
These are hollow tubes that are placed between a lens and the camera body, and they simply move the lens elements farther away from the film plane, thus increasing magnification. Because there is no glass in the tube (just air), image quality will not be degraded by optics that are of lesser quality than the lens you’re using. As a general rule, the magnification you can achieve using extension tubes is relative to the focal length of the lens you use them with, and the “formula” is:
UNDERSTANDING MACRO'S LIMITATIONS
As the saying goes, “You can’t have it all”, so the increased magnification you get with macro comes at the expense of depth-of-field (DOF). Depth-of-field is “how much” of the picture is in sharp focus. There is an inverse relationship between magnification and DOF…the more magnification you get, the less DOF you get.
Of special note is the DOF difference between point-and-shoot digital cameras and SLR cameras with macro lenses. The physics behind this are quite complex, but because the lens on a P&S digital is so close to the digital sensor, the lens must have an extremely wide focal length in order to project the image onto the sensor. Wide lenses by nature provide greater DOF than longer lenses (all other things being equal), so P&S digital cameras are capable of providing a significant amount of DOF relative to their weak magnification ratios.
Another limitation to higher magnification is the “camera shake” factor that increases with magnification (and with the weight of all that equipment…my full rig weighs over 6 pounds). If you’ve ever looked through a non-stabilized 300mm telephoto lens, you know that even as you breathe, your field of view will wobble as you find it hard to hold the lens steady at that long focal length. The same is true of high magnification; although it’s not “zoomed in” on the subject (it’s magnified), the effect is the same…it’s very difficult to hold still when highly magnified.
Another technical difficulty in shooting macro, especially “extreme” macro, is getting the focus point at the optimal plane. Focusing at the right point becomes critical because of the very limited DOF, so you need to identify the part of the bug that will yield the most drama, and this can depend on exactly what you’re trying to show. On many bugs the eyes (and even bug “pupils”) lend a dramatic connection between them and us, so that is what you might want to have the sharpest focus. On the other hand, many bugs’ wings have similar structure to a stained-glass window, and you might want to draw attention to those patterns. Whatever it is that captures your eye should also capture the eye of your audience, and that is what you should focus on.
Wide-angle Macro
This an interesting and powerful technique. Simply add a thin (12mm) extension tube to a wide angle lens and go macro. You get great perspective and you can focus almost to the lens itself. It can get a little tricky to light the shot since the lens will be very close to the subject, and it is tough to do with skittish creatures - but the results are often very rewarding.
Telephoto Macro
Once again, adding extension tubes to a lens can allow it to focus close and in the case of telephotos, move them into the macro range. You can use as many extenders as you need; remember though that each extension costs you a little light and makes the whole setup more vulnerable to shake. These rigs do, however, allow you to stand back some considerable (6-10 feet) distance and still fill the frame with larger insects such as dragonflies. For more on the effect of adding extension tubes to a wide variety of lenses.
Final Tips:
- If you are using flash, watch out for vegetation in the foreground which will flare white in the final image (and possibly cause the image to be underexposed)
- If vegetation is obscuring your shot, gently tuck it out of the way. In some cases, you are justified in doing a little "gardening" or "weeding" as long as you are not pulling up endangered species.
- Sometimes it is possible, safe and ethical to move the subject to a better lit or more accessible area.
- A focusing rail or macro slider is a useful accessory when working on a tripod.
- If you can't get enough magnification with a single macro lens, you can add extension tubes to get closer. To get more magnification without sacrificing working distance, you can add a multiplier; however many multipliers won't fir onto macro lenses. To get around this, use my secret macro trick (as opposed to my secret macro system).
With the magnifications common to macro work, depth of field is a constant problem. It is very difficult, for instance, to get all of an insect in focus. There are several tricks you can use to minimize this problem:
- Align yourself so that the majority of the subject is parallel to the film plane (i.e. don't look face on at a long, skinny insect like a dragonfly, look at it from the side or the top). Be careful to be exactly parallel; the head and the tail should both then be in focus.
- Use a f-stop of 16 or greater (22. 32, 64, etc.)
- Use less magnification.
- Use the depth of field preview feature, if available on your camera. This closes the lens down to the selected aperture before the shot is taken so that you can check the depth of field visually. The viewfinder may get very dark when you do this, however.
- Some cameras have a depth of field mode. In this mode you focus on the closest and furthest thing you want to be in focus and the camera tries to pull it off. Good luck, but who knows?
- Use flash if you need more light to keep the f-stop and the shutter speed where you need them.
WHAT DOES "LIFESIZE" MEAN? What is meant by “true macro” is the ability to produce an image that is as big (or bigger) on the film plane (or digital sensor) as it is in real life…this is where we get the term “lifesize” or “1:1 magnification” as it is used in macro lingo. The term “magnification” is important because true macro photography does not involve “zooming” or getting closer to a subject; instead, we are relying on the lens itself to magnify the image that will be projected onto the film plane. In other words, just because your Sony F717 has a minimum focusing distance of 2 cm doesn’t mean that it can produce “lifesize” images by merit of its ultra-close minimum focusing distance. Zooming and how close you are to the subject really have nothing to do with macro; it’s mostly in the magnification properties of the lens. Still, just because you don’t have a true macro rig doesn’t mean you can’t get great insect close-ups
EQIPMENT CHECk
if you want to go beyond typical close-up insect photography with your SLR, you’ll be entering the world of true macro photography (called “photomacrography”), and dedicated macro equipment will be necessary. If, however, you want to stick with your digital point-and-shoot (which is a great tool for close-up work), you’ll have to work on getting “closer” close-ups instead of doing true macro photography.
The equipment options for an SLR shooter (film or digital SLRs) are wider than for the point-and-shoot camera owner. The equipment that an SLR user might employ includes true macro lenses (be careful: just because a lens says “macro” doesn’t mean it’s true 1:1 macro), extension tubes, close-up filters, bellows, and “reversed” lenses. The latter two methods, although effective, are more troublesome than the first three, so we’ll stick to discussing those
The equipment options for an SLR shooter (film or digital SLRs) are wider than for the point-and-shoot camera owner. The equipment that an SLR user might employ includes true macro lenses (be careful: just because a lens says “macro” doesn’t mean it’s true 1:1 macro), extension tubes, close-up filters, bellows, and “reversed” lenses. The latter two methods, although effective, are more troublesome than the first three, so we’ll stick to discussing those
LET'S TALK LENSES
The easiest and most efficient way to get true macro photos is to use a true macro lens. Most manufacturers make 1:1 macro lenses in several focal lengths ranging from 50mm to 200mm, and they are always fixed focal lengths. These are low-maintenance lenses that you put on the camera and operate just like any other lens.
Macro lenses typically have very short minimum focus distance ratings; minimum focus distance is the “closest” distance you can be to the subject before the lens loses its ability to focus. Short focal length macro lenses have lower minimum focus distance than longer focal length macro lenses. What this means to the macro photographer is “working distance”; working distance is the measure of length between the end of your lens and your subject when at a 1:1 magnification ratio. A longer lens will give you more working distance while maintaining 1:1 true lifesize magnification.
For example, Sigma makes three very good macro lenses in the three focal lengths 50mm, 105mm, and 180mm. The working distances are as follows:
| Macro Lens: | 50mm | 105mm | 180mm |
| Working Distance : | 1.6 inches | 4.7 inches | 9.1 inches |
This means that if you use the 50mm lens, you will have to be about 1½ inches away to get a lifesize shot, and if you use the 105mm lens, you’ll have to be just under 5 inches away. But if you use the 180mm lens, you can be up to 9 inches away from the subject and still get a full 1:1 lifesize macro shot. Obviously, this is important with either dangerous or highly skittish insects like butterflies…more working distance allows you to get 1:1 without getting too close.
One effective way to squeeze even more working distance out of some lenses is to use teleconverters (TCs), which go between the lens and the body (like extension tubes do); TCs contain glass elements that effectively change the focal length of the lens. Continuing with my example above, if you put a 2x TC onto the Sigma 180mm macro lens, you will effectively double the focal length of that lens to 360mm and it will still maintain its true macro 1:1 magnification. But the real benefit of doing this is that it will also double the working distance of that lens to over 18 inches. As an added bonus, you could even gain some extra magnification this way because if you use this combination at the “normal” working distance of 9 inches, you are actually shooting at 2x lifesize (2:1)! I should mention here that there is a price for just about everything, and the price of using TCs is loss of light reaching the film plane by the number of stops equal to the magnifying property of the TC. For example, a 2x TC cuts out two full stops of light, and thus will “slow down” your lens by 2 stops. This really doesn’t matter in macro, as you have already learned, because you will be stopping down anyway in order to maximize depth-of-field.
There are some other highly-specialized macro lenses available from Canon and Minolta that allow for “extreme” magnification without any extra attachments such as tubes or teleconverters. The Minolta lens allows magnifications up to 3x lifesize (a 3:1 reproduction ratio) and the one I use, Canon’s outstanding MP-E lens (read my review of this lens here), allows magnifications of up to 5x lifesize (5:1). These lenses are expensive, difficult to master, and hard to handle, but if you practice with them and become proficient in their use, you will reap the benefits of some utterly stunning extreme close-up shots.
THE "ART" OF THE SHOT
Before you fire the shutter for the first time, you should prepare yourself mentally. The first thing to think about is putting yourself in a frame of mind to compose the image in a non-clinical way; I prefer to approach each shot as if I am doing a “portrait” of the insect. Try to avoid an aerial perspective like you might see in a field guide; avoid what I call “shoe view”, or showing the bug as the bottom of your shoe might see it, as demonstrated by the ladybug at right. Remember, the science of the shot may be your advanced equipment, but the art of the shot is capturing the subject in a unique and dynamic pose. Think about what makes this bug so interesting, and then try to highlight that feature. For example, butterflies have a built-in “straw” called a proboscis, and they use this straw to draw nectar out of blossoms. If you can get an “action shot” of a butterfly dipping its straw, you’ve got an interesting and dynamic photo.
One of the first things you’ll notice is that some insects are extremely skittish (butterflies, damselflies, and dragonflies) while others aren’t bothered by your presence (ladybugs, many grasshoppers). You’ll see that some insects are constantly moving about (ants, bees) while others prefer to sit still for extended periods (many spiders and assassin bugs). And others, like leafhoppers and plant hoppers, don’t seem to mind being photographed, but will shyly turn their back on you, forcing you to change position constantly. The point is that you should invest some time getting to know the common behavior of your tiny subjects before firing the first frame.
