It is unusual to choose a macro lens as the first addition to a standard kit lens. And yet, it is a logical choice. Not only because macro photography is very popular, but also because a macro lens can be used well as a portrait lens. Each and every camera brand and lens brand produces at least two macro lenses. How do you make the right choice then if you know that the focal length and the set aperture of the macro lens greatly determine the final image? And to complicate things, the size of the image sensor too is iconic. In this article, I will show on the basis of practice pictures what macro lens is a good choice.
What is macro?
At many cheap zoom lenses, it says the word “macro”. Usually it is meant that you can set a little bit closer than usual. Flies and bees can not be captured size filling; you need a “real” macro lens for that. Generally, it is held that a macro lens can project the subject 1 on 1 on the sensor. This means that the subject is 24 x 36 mm high at a full-frame camera. At a crop camera, it is approximately 16 x 24 mm. In the overview macro lenses, I have put the most popular macro lenses with their specifications in a table. I restrict myself here to lenses that fit on digital SLR cameras equipped with a full frame sensor or an APS-C sensor. The latter has a crop factor of 1.6 at Canon and 1.5 at Nikon, Pentax and Sony. Lenses specially designed for macro bellows are not included in the table.
Characteristics of a macro lens
It is logical that a macro lens should be adjustable nearby. Because sometimes flat subjects (think of stamps) are photographed, there should be no image field curvature. In addition, a macro lens draws the sharpest in the nearby area. This is different than with normal lenses; these are corrected at a distance of 40 times the focal length. Due to this platform of demands, macro lenses are almost never zoom lenses and the maximum aperture is somewhat limited. Due to this last restriction, most macro lenses already draw very sharp at full aperture.
Used equipment and tools
For the first series, the subject is a chess game and for the second series reading glasses. Successively, three different macro lenses from Sigma are placed on a Canon 5D MK 2 and a Canon 40D. The 5D MK 2 is a full-frame camera, while the 40D is a crop camera with a factor of 1.6. Because the depth of field is determined by the aperture, two values per combination are used, namely f/2.8 and f/8.0. For each series, we tried to photograph the subject the same size.
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Canon 5D MK 2 with Sigma 50 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 50 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 105 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 105 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 150 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 150 mm/2,8 at 8 |
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Canon 40D with Sigma 50 mm/2,8 at 2,8 | Canon 5D 40D with Sigma 50 mm/2,8 at 8 |
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Canon 40D with Sigma 105 mm/2,8 at 2,8 | Canon 40D with Sigma 105 mm/2,8 at 8 |
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Canon 40D with Sigma 150 mm/2,8 at 2,8 | Canon 40D with Sigma 150 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 50 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 50 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 105 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 105 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 150 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 150 mm/2,8 at 8 |
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Canon 40D with Sigma 50 mm/2,8 at 2,8 | Canon 40D with Sigma 50 mm/2,8 at 8 |
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Canon 40D with Sigma 105 mm/2,8 at 2,8 | Canon 40D with Sigma 105 mm/2,8 at 8 |
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Canon 40D with Sigma 150 mm/2,8 at 2,8 | Canon 40D with Sigma 150 mm/2,8 at 8 |
The pictures taken with the 50mm look quite different from the ones taken with 105 or 150 mm. The difference between the latter two is not so big however. The longer the focal length, the more thick-set the picture is. The difference between optic angle of a 105 mm on a crop camera and a 150 mm on a full-frame camera is small. The background is much quieter and therefore more attractive at the last combination.
Depth of field
Using the familiar program Dofmaster, see www.dofmaster.com, you can determine the depth of field. The following pictures show what that means in practice. Again, two cameras, three lenses and two apertures. The angle photographed with is constant at all recordings. Furthermore, the width of the subject is the same everywhere.
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Canon 5D MK 2 with Sigma 50 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 50 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 105 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 105 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 150 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 150 mm/2,8 at 8 |
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Canon 40D with Sigma 50 mm/2,8 at 2,8 | Canon 40D with Sigma 50 mm/2,8 at 8 |
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Canon 40D with Sigma 105 mm/2,8 at 2,8 | Canon 40D with Sigma 105 mm/2,8 at 8 |
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Canon 40D with Sigma 150 mm/2,8 at 2,8 | Canon 40D with Sigma 150 mm/2,8 at 8 |
Macro lenses in practice
To get the entire fly sharp, you need much depth of field at macro photography. That means that you must aperture. This can cause for the background to be displayed very restlessly. From practice pictures, it appears that the background is displayed blurredly at the same aperture in case the focal length is longer. But a somewhat longer macro lens has even more advantages. Because the distance to the subject is greater, the less you scare off the fly or bee that you wanted to photograph. You also less troubled by your own shadow as a photographer. Yet, there are also disadvantages to a strong telephoto macro lens. The weight is high, the size is large and the purchase costs are high. In addition, the chance on movement blurring increases. And if you want the best blurred background parts, you have to buy a full frame camera as camera.
Macro lens as portrait lens
If you make a portrait, you want the face to appear true to nature on the picture. If the focal length is too short, at a frontal portrait the nose and sometimes the chin are greatly increased. And if the focal length is too long, the face is depicted too flatly. A (too) long focal length has two other drawbacks. First, you need a bigger studio or recording space. And second, due to the greater distance to the model, you have less contact with that model. As a happy medium, at a full-frame sensor, usually a focal length of about 100 mm is taken. Converted to the APS-C sensor size with a crop factor of 1.5 or 1.6, it will give you a focal length of about 70 mm. Not for nothing Sigma offers a macro lens of 70 mm. Because these focal lengths also suffice at macro photography, portraits are sometimes made with a macro lens.
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Canon 5D MK 2 with Sigma 50 mm/2,8 at 2,8 | Canon 5D MK 2 with Sigma 105 mm/2,8 at 8 |
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Canon 5D MK 2 with Sigma 150 mm/2,8 at 8 | |
Overview macro lenses
Compared to other lenses, like telephoto and zoom, the supply of macro lenses is limited. A new development is the inclusion of image stabilization. Canon, Nikon and Sigma run first with this. At Pentax and Sony, it is unnecessary because at those cameras, image stabilization is built in the camera itself. Another development is the macro lens with a focal length of 30 or 35 mm especially suitable for cameras with an image sensor of the APS-C format. The pictures show that the use of such a lens is very limited.
