Foreword

Good afternoon, Habr!
I am pleased to present to you the promised third part of the article about the NX-series cameras from Samsung. If you haven’t had a chance to read the first part (it talks about the NX300 and NX2000 cameras), please , you can learn about fixed focal length lenses from a previous post , and today we will dwell on zooms in more detail.

Theory: zoom lens

The zoom lens is undoubtedly the most convenient and versatile solution for the camera: you can vary both the viewing angle and the approximation of the displayed object. This is achieved in a very simple way, which is shown in the picture below:



One of the lenses (in modern solutions this is a whole group of elements) moves relative to the fixed parts of the lens, changing the focal length (and the field of view, respectively, too). You can read about history and general design features on Wikipedia , but we are waiting for very specific glasses.

I want to remind you that NX-lenses have several abbreviations that show the use of a particular technology in a particular model.

ED(Extra-Low Dispersion) - A lens that contains one (or several) lenses from materials with ultra-low dispersion of light. Reduces the amount of chromatic aberration.

SSA (Super Sonic Actuator) - The lens is equipped with a silent autofocus motor based on an ultrasonic drive. Allows the autofocus system to work faster and more accurately.

OIS (Optical Image Stabilization) - Optical stabilization system. The lenses of the lens have a special “suspension”, which is electronically controlled and reduces the effect of shaking on the quality of the frame. Allows you to shoot at a slower shutter speed and / or in difficult conditions.

I, II, III, IV (1, 2, 3, 4) - Roman numerals denote the generation of a particular subsystem (larger is better) or the generation of the lens itself.

Marking the focal length and aperture, I hope, is clear to everyone.

Practice: zoom lenses

Fixes, of course, give a beautiful picture and allow you to get excellent shots, but when you travel, take an event or just went for a walk with a camera, carrying 3-4 lenses for all occasions is quite difficult, and changing the lens itself may cause the frame to “leave”. And it’s not always possible to change the lens: dust, rain, transport, shaking - a million conditions hamper the process. A good zoom lens is a versatile and very convenient device that allows you to get great shots in a variety of conditions. It used to be problems with calculating complex systems - now we have powerful computers, a ready-made database of hundreds of solutions, proven materials, features that simply did not exist 20-30 years ago and most importantly - the desire to make a convenient and universal lens. Of course,

20 - 50mm F / 3.5 - 5.6 ED - II

The 20-50 is a whale lens for junior division cameras. A good (read - popular) set of focal lengths, a very compact body in the "folded" state, an average aperture ratio and one element with ultra-low dispersion of light.



Made of plastic, it has a manual “fuse”, which removes the extra “trunk” in an inactive state. Overall, characterized by two words: compact whale. You should not expect exorbitant quality, but no one demands this from him.

Aperture
F3.5-5.6 (minimum - F22), Number of blades: 7, rounded outline

Minimum focal length
0.28m

Maximum magnification
~ 0.22X

Viewing angle
70.2 ° ~ 31.4 °

Number of element groups
9 elements in 8 groups, (1 Aspherical lens, 1 Extra-low Dispersion lens)

Filter diameter
40.5mm

Length x Outer diameter
40mm x 64mm

Weight
119g

There are not many examples of photos from it, and the glass, in essence, is “ plug ”for the camera. In principle, if you use only the green mode and not bother with Photoshop, it will do. Buying this lens separately is a dubious decision: it’s better to buy a decent fix. Sharpness and chromatic aberration are normal, (especially considering the price of the glass), vignetting also does not raise questions. And distortions ... you can’t get anywhere. Fortunately, there is Photoshop, and in most cases, few people worry about distortions, having a lens for ~ $ 190.



Photos taken at 20-50mm are easy to google, frames are quite decent:

www.flickr.com/photos/50231042@N03 »> The average price on the Yandex market: 6,990 rubles .

18 - 55mm F / 3.5 - 5.6 OIS II

The classics of the genre are 18-55 with F / 3.5-5.6 and a stabilizer. Canon, Nikon, and Pentax have such a whale lens. The reason for the popularity, probably, is that every manufacturer really has such a lens, and if everyone has one, then why shouldn’t we have it?

The Samsung variant did not go far from its counterparts in terms of the quality of the resulting image, since nothing new was invented here. Frames are better than those of 20-50, but the lens itself is almost one and a half times larger in physical dimensions: if you can somehow attach a camera in a pocket of a jacket or jacket from 20-50, then from 18-55 it will have a probability of 146% get in the way.



The characteristics are as follows:

Aperture
F3.5-5.6 (minimum - F22), Number of blades: 7, rounded outline

Minimum focal length
0.28m

Magnification
~ 0.22X

Viewing angle
75.9 ° - 28.7 ° The

number of groups of elements
12 elements in 9 groups (1 Aspherical lens)

Filter diameter
58mm

Length x Outer diameter
65.1mm x 63mm

Weight
119g

Overall - a whale like a whale: quite decent shots, but to expect nothing special is necessary. Distortion, resolution, vignetting and “barrel” are direct consequences of price and “whale” origin, all parameters are normal, especially if you shoot the camera directly in JPEG: it knows all the frame parameters and will be able to correct all of the above optical flaws in automatic mode. The average price on the Yandex market: 10 500 rubles .

12-24mm F / 4-5.6

Super wide with zoom function. To be honest, it’s not entirely clear why such a set of focal lengths is needed when it can easily be replaced with a much more fast 16mm fix. For a long time I tried to use this lens for its intended purpose: shooting a landscape and / or city landscape, but much more decent shots were obtained by 10mm Fisheye than by 12-14.



This is due to the low quality of the lens itself: chromatic aberration at the edges of the frame was 2-3 pixels, the color border, of course, is removed in Photoshop, but this is an extra movement and loss of image quality. The overall resolution of the lens is small, my specimen also had a misalignment of the lenses. Perhaps I just got a test sample that was badly battered by the crazy hands of the previous reviewers (the glass really did not look new).

The characteristics of the lens are as follows:

Aperture
F4-5.6 (minimum - F22), Number of blades: 7, rounded outline

Minimum focal length
0.24m

Maximum magnification
~ 0.14X

Viewing angle
99 ° ~ 60.7 °

Number of element groups
10 elements in 8 groups

Filter diameter
58mm

Length x Outer Diameter
65.5mm x 63.5mm

Weight
208g

With a weight of almost 210 grams, I would prefer any of the wide-angle fixes. I won’t show my terrible shots, because there are suspicions that the copy was so-so, but quite decent photographs were taken on the Internet, although they do not reach the fixes: However, there is another opinion













, and there is a comparison with two fixes, and what to believe is up to you.

The average price on the Yandex market: 18 980 rubles . For this money, you can take any two fixed-focal wide-angle (including Fisheye), and still have some cookies for tea. So I would choose 10mm + 20mm, and leave 12-24 until better times (and the second version of the lens itself).

Interlude

There are only two lenses left, but before I go to them, I would like to say a few words about whales and the wide-angle. Naturally, against the background of fixes, they look a little faded, but two important facts are worth noting. The first - 20-50 and 18-55, most likely, you get along with the camera (20-50 with the NX1000, 1100, 2000, and 18-55 with the NX200, 210, 300, 20), so that anyone can remove "out of the box ". The second fact - at 12-24 there are a bunch of decent reviews on the Internet. And we still have two of the most interesting lenses - we will discuss them.

18 - 200mm F / 3.5 - 6.3 ED OIS

From a wide angle to an ultrasound, fast enough and with an optical stabilizer, the most versatile travel lens. Of course, you have to pay for universality, and not only in rubles, but also in mass, dimensions, compromises as a picture at the extreme positions of the zoom, but you can’t do anything here - physics.



The characteristics of the lens are as follows:

Aperture
F3.5-5.6 (minimum - F22), Number of blades: 7, rounded outline

Minimum focal length
0.50m

Maximum magnification
~ 0.28X

Angle of view
75.9 ° - 8.0 °

Number of element groups
18 elements in 13 groups, (3 Aspherical lenses, 2 Extra-low Dispersion lenses)

Filter diameter
67mm

Length x Outer Diameter
105.5mm x 72.0mm

Weight
549g

As you can see, they did not save a second on the construct.

Distortion, in general, is typical for lenses of such a construct: here it reaches -4.3% at the “short” end and smoothly reaches 1.3% at 200mm.

Vignetting, respectively, also “floats” depending on the focal length. The image is darkened at the corners of the frame at the short end ~ 1 EV, at the long end - 0.5 EV. The indicator is acceptable, and the correction of vignetting is not such a big problem: often, the camera knows which lens is attached to it, and either corrects everything itself, checking the data in the firmware, or writes information to the SRW file so that you can then apply Auto correction in a graphical editor.

The resolution of the lens, like all other characteristics, is highly dependent on the focal length. In the center of the frame under normal shooting conditions, everything is fine: at the edges there is some “softness” of the image, which, in principle, cannot be avoided with such a spread of focal lengths.

www.photozone.de/images/8Reviews/lenses/samsung_18200_3563/mtf.png "/>

And of course, the frames. It shoots this universal lens very well, although it suffers from its versatility: At focal lengths from 18 to 50-60mm then the picture quality drops, but I think the percentage of frames at focal lengths greater than 100mm is usually small, so if you choose “take medium-quality photos” or “take nothing”, I think many will prefer the first option. Autofocus works quickly and practically silently, which, in principle, safely affects the shooting of video and with Shooting “from the hip,” when you need to get a few frames quickly and without attracting too much attention. According to Yandex Market, you’ll have to pay about 18,990 rubles for it .

50 - 200mm F / 4 - 5.6 ED OIS II

If you describe the lens in a nutshell: simpler, easier, less than 18-200, it does not allow you to shoot close, but it copes with the far end much better (focal lengths from 100 to 200mm).



The lens characteristics are as follows:

Aperture
F4-5.6 (minimum - F22), Number of blades: 7, rounded outline

Minimum focal length
0.98m

Zoom
~ 0.2X

Viewing angle
31.4˚ - 8.0˚

Number of element groups
17 elements in 13 groups (2 Extra-low Dispersion Lens)

Filter Diameter
52mm

Length x Outer Diameter
100.5mm x 70mm

Weight
407g

High-quality plastic, a metal base, an internal focusing mechanism (the front lens does not rotate when working with autofocus or zoom movement), excellent build quality and a very nice price tag make the 50-200 a very pleasant and affordable TV set. Want to shoot in a concert from the back rows? You are welcome! An optical stabilizer allows you to compensate for up to 4EV stops, and a good weight distribution will allow you to keep the camera on weight for a long time without suffering from lead-filled hands.

The sharpest shots, of course, are achieved with the aperture covered up to F / 8, and held to F / 11, after which the diffraction limit starts to slightly spoil the picture, however, at the long end up to F / 22, the resolution along the edges and in the center remains at a quite acceptable level.

At 50mm, the aperture resolution gradient looks like this:

Starting from F / 5.6 to F / 8, you get a jingle-sharp picture over almost the entire field of the frame.

For 100mm, the picture is a little worse, but still remains within reason:


For 200mm, all the results are even lower, but here mother physics comes into force with its own laws. If you want maximum clarity - take 200mm fix.

Chromatic aberrations are practically absent at 50mm and are on the verge of being distinguishable at a maximum focal length of 200mm.

In the worst case scenario (open aperture at 200mm focal length), vignetting is ~ at the level of 0.5 EV, in all other cases - in the region of 0.2 ~ 0.3 EV. And now the most delicious: the average price on the Yandex market is just









9 890 rub . For such a lens - mere pennies. If you already have 45mm, 18-55 or 20-50, then this is the first candidate to purchase, if you feel the need for photography "at a distance".

Zoom Lenses, Summary

In the plate below, I collected all the lenses, their pros and cons.

Model	pros	Minuses	A comment
12-24mm	Well assembled, allows you to shoot both indoors and outdoors;	Price, variation in build quality, weight, dimensions;	I would prefer 2 fixes instead of this lens. 10mm + 20mm or 10mm + 30mm will give the same scope for creativity.
20-50mm	The cheapest whale. Compact, makes good shots (for its price);	The cheapest whale;	It’s not worth buying separately, but if it’s included, you can use it until you decide what to take for a replacement.
18-55mm	Второй кит. Больше, тяжелее, лучше, чем 20-50, оснащён стабилизатором;	Это всё ещё китовый объектив со всеми вытекающими из этого недостатками;	Неплохое начальное стекло, но без изысков. Покупать, имея 18-200 или 20-50 нет смысла.
50-200mm	Цена, вес, качество картинки (особенно с учётом цены);	Качество изображения на длинном конце могло быть и повыше;	Очень достойный вариант в пару к 18-55, 20-50 или фиксам, если вам действительно нужен диапазон фокусных расстояний от 50 до 100-200mm.
18-200mm	Универсален, позволяет заменить связку 18-55 и 50-200.	Дорогой, тяжелый, универсальность негативно влияет на качество картинки на «длинном» конце;	Ему бы цену поменьше или оптическое качество получше — был бы золотой серединой. А так — дороговато.

In the next post, I’ll talk about the available accessories and buns for NX cameras or pick out SRW files on the topic of “pulling” parts - your choice!