The difference between near and macro shooting is fluid. As a close-up, you will identify an image whenever a relatively small section of a large object is imaged – for example, a distinctive detail of a car. The rule is a sharp reduction of the subject on the image sensor.
How to define macro
In the case of macro images, however, one is looking for ways to capture very small motifs in an approximately real size or even enlarged on the image sensor. The macro perspective plays an important role not only in nature, but also in property surveys: collectors of small objects such as watches, jewelery or minerals are happy to use them to document their treasures and to exchange ideas with like-minded people. In any case, dipping into the photographic microcosm causes a lot of surprises - both positive and negative. Because the close-up photograph is not without problems. If you are new to macro photography, you should expect a lot of rejects. Why this is so and how to systematically increase its hit rate, this contribution clarifies.
How macros become possible
Traditionally, the macrophotography is defined by the imaging scale, whereby the limits of the macro range are usually from the tenfold reduction (1:10) to the tenfold magnification (10: 1) of an object at the recording medium. The imaging scale is independent of the recording format used. Therefore, if an object is photographed 1: 1 on the image scale, it has exactly the same size as in reality in the image sensor, and the image is half as large in the case of 1: 2, whereas the 2: 1 image is twice as large as the real image. The actual recording format only plays a role with regard to the resulting image excerpt.
Scale and focal length
At the time of analogue film, the photographers knew quite well about the size of their recording format, but this still applies to the "full-screen" (36 x 24 cm) film oriented to small-format film. Also known are the sensor dimensions of the four-thirds format (17.3 x 13 mm, crop factor 2.0) for the 1-inch sensors that Nikon uses for the System 1 or Sony on the RX100 (13 , 2 x 8.8 mm, Crop factor 2.7). But the APSC format is not exactly defined, and the possible dimensions vary between 22-23.5 x 15-16 mm and the associated crop factors are between 1.5 and 1.6
Macro and Autofocus
Many owners of a compact camera are likely to be at a loss when asked about the size of their recording format. In addition, the imaging scale does not say anything about the size of an object after being shot - for example on a print from the inkjet or printed in a magazine. For this reason, the pragmatic question nowadays replaces the imaging scale: what technical means do I need to image a small object on a given image sensor? When testing macro lenses in ColorPhoto, e.g. With a sensor-related scale and the always same template image-filled.
Let's stay with the compact cameras. Most of them offer a macro setting, which allows for small recording distances in the centimeter range and thus almost full size images of small objects. The small sensors and short-focal-length lenses provide a desirable gain in sharpening depth in the macro range. Even standard zoom lenses for system cameras often allow macro shooting without additional tools. The Sigma 2.8-4.5 / 17-70 mm, for example, has a macro-suitability up to a scale of 1: 2.7, which corresponds to an approximately three-fold reduction of the real subject in the image
Special macro lenses, such as the AF-S DX Micro-Nikkor 3.5 / 85mm G ED VR or the Canon EF 2.8 / 100 Macro L IS USM, allow for an imaging scale of up to 1: 1; They can be combined with extracting devices such as intermediate rings or a bellows device.
An inexpensive entry into the macrophotography allows Nahlinsen, which are available in different strengths and as filter are screwed in front of the front lens. They are for the lens, which is the reading glasses for the far-sighted: an optical aid for the proximity. As with the glasses, the strength of the close-up lens is given in diopters. Nahlinsen kits consist mostly of four specimens of different strength, often up to 4 diopters. Stronger close-up lenses (e.g., 10 or 20 diopters) are available in a particular case. Close-up lenses shorten the focal length of the lens and allow imaging scales to be about 1: 1.
Hint: Make sure you do not mind because the picture quality with the close-up lens is very modest when the aperture is open.
If the distance between the image sensor and the diaphragm plane of the lens becomes larger than the distance between the diaphragm plane and the subject, a normal lens should be used in retrospect to improve the imaging quality. Retrostellung means that the front lens looks towards the camera and the bayonet towards the motive. This can be realized with a reversing ring, which has a thread on the one hand, matching the filter thread of the lens, and on the opposite side a connector for the camera bayonet. Depending on the lens used, a more or less pronounced macro-effect is produced by the retro-position. Additional intermediate rings or a bellows device expand the setting possibilities. A special form of the reversing ring is the Novoflex EOS-Retro, which allows the electrical transmission of all EOS camera functions thanks to a cable connection.
Intermediate rings are an extension of the lens extraction and thus a cost-effective alternative to the bellows device. Usually three rings of different lengths are combined into one set. With a 50 mm lens (equivalent to KB), an imaging scale of 1: 1 is generally possible. Particularly recommended are car inter-rings, in which all camera functions including the aperture measurement and the autofocus are retained. Auto-intermediate rings are partly from the camera manufacturers themselves, but also from foreign manufacturers such as B.I.G. Available
A bellows device is a variable pull-out extension, the pull-out can be varied infinitely by feint drive. Depending on the lens focal length, you can achieve imaging scales up to 10: 1 (tenfold magnification) and immerse in motifs that remain invisible to the naked eye. Automatic bellows devices have the advantage of keeping the aperture measurement and the flashing of the aperture, and even on the autofocus with a few models such as the Novoplex Balcan AF. Bellows devices are usually fitted with macro lenses. They can also be combined with other fixed focal lengths or zoom lenses.
If a digital camera with an image sensor in 35 x 24 mm format and a 50 mm lens is used, the imaging scale is 1: 1 if the extension extension corresponds exactly to this focal length. The complete extension therefore corresponds to the double focal length (in this case: 100 mm). However, if the focal length is halved when the extension is extended, the image magnification is doubled: 50 mm extension extension results in a 2: 1 image scale for a 24 mm lens.
Sharpening depth and image quality
The same applies to the distance of the object: With the same extension, a 100 mm lens is twice as great as the subject with a 50 mm focal length. This means that very high imaging scales can be achieved with short focal lengths but with a small distance to the object. Longer focal lengths, on the other hand, enable greater shooting distances, more work comfort and a more flexible light guide.
For comparison: For a macro shot at a 1: 1 scale, the front lens of a Micro Nikkor 3.5 / 85 mm G ED VR is just 150 mm away from the subject, while the distance from the AF-S DX Micro Nikkor is 2.8 / 40 mm to less than 40 mm. The larger recording distance for longer focal lengths is favorable with regard to the flight distance: Small creatures tolerate the approaching front lens of a lens only to a certain point before they take flight.
Also interesting is
On the other hand, this gives a greater scope for the light guidance with macro flash units or LED lights. Take into account that the use of the sun visor can shrink the distance to the object again. And also with regard to the shading of the motif, the sunblind is often problematic. For this reason, they are used only if they have discernible advantages for the picture quality in the specific recording situation.
In the case of static objects, you can do without the focus: either by focusing manually or by varying the distance between the front lens and the object, after having previously defined the image scale. If the tripod is used, an adjusting slide is very helpful. Exceptionally accurate focusing is possible in the Live View mode on the monitor of the camera when you switch on the magnifying glass and focusing aids such as peaking - sharp edges are color-coded. If the camera monitor is also pivotable, shooting near the ground is much more comfortable. Another option is to use the camera in combination with a smartphone or tablet in remote mode. Then the live image is visible on the smartphone or tablet, no matter where the camera is.
When photographing small creatures, this works less well because you often need to change position with the camera. With the autofocus you will get a shot more often in this case. If you have an SLR camera in use, you will have better maps with the phase AF of the camera than with the mostly sluggish contrast AF in live view mode. In contrast to mirrorless system cameras, some of them are as fast as the best SLR cameras with live AF in the live view.
Tip: In case of doubt, increase the recording distance and do not try to photograph the object in full format. The gain in sharpening depth increases the probability of the hit, and many cameras now offer enough reserves for subsequent image cuts thanks to high-resolution image sensors with over 20 megapixels. In the case of SLRs, if possible, activate the mirror pre-triggering to avoid possible vibration from the mirror beat.
Due to the short recording distances, the macrophotography is confronted with a low depth of sharpness, which is the design element and the obstacle at the same time. On the one hand, the transition from sharp to fuzzy picture parts creates the impression of depth in the picture. The selective sharpness makes the photo more plastic and makes the parts in the focus area the sharper.
The downside of the medal is that sometimes it is not possible to focus on all the important details. The photographer must therefore decide how small the focus range of the subject can be. For orientation: With regard to the small picture format, the sharpening depth is 1: 1 at the imaging scale and hardly more than 2 mm at the aperture 16. No problem if, for example, A clockwork in the reprostil want to map frontally - a theme however with motives with more spatial extent.
As a matter of fact, the sharpness depth can be increased by fading, with most lenses achieving their maximum performance by fading two or three steps. For example, if your macro lens has a starting aperture of 1: 2.8, you can expect very good to good results at aperture 5,6, but also at aperture 8 and often aperture 11. If the shutter is darkened - which is often unavoidable in macro shooting - the diffraction of the beams reduces the general sharpness.
Fine details in the motive are then no longer pin sharp, but slightly faded. This is especially important when high-resolution macro lenses are in play. In connection with simple pre-focus lenses (not achromats), which in any case do not allow a maximum of sharpness performance, the improvement of the quality by means of fade-out is more important.
A special method of increasing the sharpening depth in macro images is the so-called focus stacking. For this, several shots with different focus are made. Subsequently, the individual recordings are then combined with software to form an image with consistent sharpness. This is possible, for example, with the current versions of Photoshop or with special software such as Helicon Focus, available in various versions at prices starting at $ 30 (one-year license).
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