What is removing the lens of a fish eye. Fishing eye lenses. What is distortion

Over the past three years, our team has shot more than 10,000 spherical panoramas. With such volumes of work, we are constantly trying to develop equipment and shooting technology. Saving time in one minute on each panorama allows us to save for shooting day from one time. And obtaining quality source photos allows you to save a lot of time on processing and assembly. We have reached the limit in the photographer shooting performance: 40-110 points per day (depending on the conditions). Further scheduled events could add, speeds, quality and comfort of shooting, but do not increase productivity.

Initial data

The shoot place: Large chemical production.
Manfrotto: Tripods 190 and 055 models, heading heads for spherical panoramas, level heads, patent covers.
Cameras: full-frame. Basic - Nikon 750, Canon 5D-II (spare). In the future, we turn on Nikon completely.
Lens: SAMYANG 14MM F / 2.8.
Shooting: in RAW format. Most is removed in one pass (6 frames) with the top nadyr. In some cases, when removable equipment fit close to the point of shooting, we remove into two rows without nadir. In contrasting conditions, the shooting is removed with HDR to cover the entire range of contrast from lights to the shadows. The customer is transmitted to a reduced to 10,000 points along the long side.

Assembly: Kolor Autopano Giga program. When shooting 14 mm lens in 2 rows, a good overlap between two rows is provided, and there is no problems with the assembly. But when shooting "1 row + Nadir", Nadir gives small passing in places of connection with nearby. To ensure minimal overlap of the nadir, we are forced to raise a horizontal panorama series of 5 degrees up. So, we completely get rid of "holes", however, somewhat insufficient overlooking areas between nearby and nadir remain. Naturally, a qualitatively "sew" a number and nadir in this case (almost) is impossible. In addition, Samyang 14mm, having a complicated distortion, only aggravates the problem. Therefore, in almost every panorama, we have the places of an inaccurate connection ("Ghosts"), which have to manually "finish" in Photoshop. These are the most significant labor costs at the post-processing phase.

What I wanted

Expand the angle viewing angle, that is, to reduce its focal length. This will allow you to get rid of or, at least, reduce the number of double panoramas. The second reason for increasing the viewing angle is to provide a larger overlap of the nadir, and reduce post-processing time.

Initially, Fishaly lenses were not considered at all due to the lack of experience of shooting with such a lens and prejudice on the quality of their image. Therefore, I pondered towards superwater lenses with a focus of less than 14 mm. Candidates were not very much if you remove the optics with a bad resolution, such as Sigma (photo on the left).

Laowa 12mm F / 2.8 - Perhaps the best candidate to replace our SAMYANG 14 mm. There are for Nikon and Canon. Good allowing ability, with a record focal length (for the time of my reflection). Disadvantages: 1) the price of 1000 US $ is high; b) Sold only by pre-order with an incomprehensible delivery time, for this is a new product and a lot of people willing to buy it all over the world.

Canon lenses in their ruler had CANON EF 11-24MM F / 4L USM zoom. Resolving the ability, judging by the tests, exceeds our Fix Samyang. But the price of 2500 US $ depresss. Be this zoom for a long time in work, I would accept. But the conditions of our filming are so complicated that there is no guarantee that the equipment will not be fatally damaged in the first shooting. So, one day, my camera, along with a tripod, flew vertically down the head of the engineer from our team. Sasha caught the falling "shell", first of the cater, then with his hands.

Nikon. I could not offer me anything except two Fishaev. But Fishai at the beginning I did not consider.

Doubt

The main doubts were that care for 12 or even 11 mm lens does not change the situation dramatically. Well, yes, it will be a little better, but I wanted a breakthrough. Doubts disappeared when I once again analyzed the values \u200b\u200bof the corners of the field of view. Our 14 mm is equal to 115.7 degrees diagonally. Laowa 12 mm gives 122 degrees diagonally, that is, will provide an increase of 6 degrees. It could get rid of the tilt of the camera up, while maintaining a small overlap of nadir. Or will increase the overlap, which may simplify post-processing, but the slope of the row of 5 degrees will remain.

Canon EF 11-24 has 126 degrees diagonally (increase of 10 degrees). This is already something. Such an angle will allow you to get rid of the chamber tilt up, in some cases reduce the number of double-flop panoramas and slightly increase the overlap of the nadir. However, I wanted to "jump off" with Canon on Nikon, for certain reasons.

Fish

From curiosity, I looked at the angle of view from Fishai - 175-180 degrees. Wow! Exactly what is needed. It is even possible that with this corner of the review we can cover a complete rotation of only 4 vertical pictures. But how to be with a decrease in quality? We will have to test. First determined candidates for testing: SAMYANG 12MM F2.8 FISH-EYE and FISHEYE-NIKKOR 16MM F / 2.8. Fisheye-Nikkor 8-15mm f / 3.5-4.5 For the time of my testing has not yet been on sale. Canon also has Fishai, but I did not consider it in terms of the above reason.

Test purpose: Whether it will be possible to get a panorama, removed Fisham, is not worse in quality than the removed SAMYANG 14mm. I will compare as permitting lenses and the ability to keep the connecting light in high contrast conditions.

Next, I found the company for renting photo equipment. Rentaphoto could provide me with both subjects lens, but, unfortunately, Samyang 12mm was only for Canon, also performed by "for video". However, in other companies, the situation with this fishee was exactly the same. Therefore, I will compare the lenses in pairs. For Nikon: Samyang 14mm and Fisheye-Nikkor 16mm. For Canon: Samyang 14mm and Samyang 12mm Fish-Eye. "Fish eyes" were tested on a diaphragm 8, as optimal. The tip on the sharpness was carried out in the text on the near rack.

Photo 1: Nikkor, Planck Heads in the frame.
Photo 2: Overlapping at 4 frame panorama.
Photo 3: "Ghosts" with insufficient overlap.
Photo 4: Small "Ghosts"

Fisheye-Nikkor 16mm

Fishai from Nikon was a small size and first it was pleased. I noticed that the bottom and side slap head enters the frame (photo 1). Hmm ... not critical, as a last resort, this place can be refused. In 4 vertical Panorama frames, formally, can be removed. But in the center of the vertical side, the overlap between the pictures is too small (photo 2). Just in case, I took a panorama for 4 frames to see if it would be possible to gather it. Panoramas stuck with very strong errors, non-working option (photo 3). It is possible that sufficient overlap would be ensured with a 5-person panorama, but the MANFROTTO head divider does not have such a division: only 4 or 6. I was forced to set a divider to 6. And therefore, it will not be possible to reduce the number of personnel even at 180- degree of visual angle (with a vertical frame). It's a pity.

With manual tip on sharpness, we use two distances: 1.5 and 0.5 meters. Nikon focus ring rotates too easy and during shooting it will easily leave from the desired distance. We will cope with this problem using a paper painting tape. Picture, when rotating the ring, "walked" in all directions. It was a feeling that I work with a hip "glass" is cheaper than $ 100. In general, unpleasant impressions. However, I have important what quality of the panorama will be collected from this lens.

Photo 5: Nikkor Right Light holds a better samyang 14 mm.
Photo 6: Permissive ability of Nikkor slightly above samyang 14 mm.
Photo 7: Nikkor resolution resolution drop islands.
Photo 8: Reducing the resolution in the corners of the Nikkor frame.

1) The planks included in the image, the Autopano Giga is discarded when assembly, that is, they can not be crushed.

2) Small "ghosts" remained, despite the fact that the overlap zones increased significantly (photo 4).

3) Right light lens keeps a little better than SAMYANG 14 mm (photo 5).

4) Nikkor resolution ability is slightly higher than SAMYANG 14 mm (photo 6). After decreasing the size of the photo up to 10,000 points - the difference is not visible.

5) There are "islands" of a strong drop in permissive ability (photo 7). I suspect that the cause of this is a strong drop in the permitting ability in the corners of the frame (photo 8). This has played a decisive role to make a decision - "not an option."

Samyang 12mm.

Samyang 12mm Fish-Eye is made kindly as his 14 mm brother. Immediately checked the alignment. At a 14 millimeter version this sick place - The lenses are almost always brushed after the plant, and when tapping on the "infinity" on the distance scale, it is possible to determine the sharpness. Everything is in order, "infinity" in place.

Photo 9: SAMYANG, LANDERS head sticks less.
Photo 10: Samyang in the corners better than Nikkor.
Photo 11: Samyang is slightly smaller than Nikkor.
Photo 12: SAMYANG Right Light keeps the best.

The manfrotto head plan also enters the frame, but significantly less (photo 9). Thought why so. As if the angle of view of this Fisha is less than Nikkor, which should not be. Ha, the size matters! The SAMYANG lens is long, its front lens is advanced relative to the head plank, so it easily falls into the frame.

The drop of resolution in the corners is not fatal, like Nikkor (photo 10). In general, the resolution of this lens is slightly lower than that of Nikkor (photo 11), but with a decrease in panorama to 10,000 points, the difference is insignificant. I fully admit that this can be explained by the fact that Canon 5D-II, which I tested this lens, the matrix has on board 21 megapixel, and Nikon has 24 megapixels.

The robust light Fishai holds better than Samyang 14mm and Nikkor (photo 12). Colors are transmitted brighter (clarified later, when executing the order). I believe that the reason for this is the best enlightenment of the front lenses in Fisha.

Panorama of 4 shots is going, but errors in the stitching are very strong, even without nadir. The miracle did not happen.

findings

We bought two samyang 12mm and were not disappointed. Fishay perfectly holds the connecting light and the sun, allows you to shoot a spherical panorama (from a tripod leg) for 7 frames. So 12 personnel panoramas for us remained in the past. This will reduce the shooting and processing time, all panoramas will be visually the same type, and not in 1 and 2 passages. The cost of lenses, whose purchase paid for the customer will return to him, at the expense of savings, on a pair of production, and, in the future, will give the customer a significant savings of the cost of photography and processing. We are glad.

PS: I thank Andrei, Rentaphoto employee, for helping in testing lenses and amazing Buddhist calm.

To create interesting effects in the pictures and give them greater expressiveness, different means are used. For example, unusual lenses. Fish eye, or Fishai, is a kind of short-focus superwater lenses with a barrel-shaped distortion.

What is distortion?

These are geometric distortion that can occur in photographs, curvatures of lines and objects. The most common variant is a barrel-shaped, the lines are strung out outside, objects become convex. Pillow-like distortion is the opposite effect, objects begin to impress concave.

Otherwise, still the barrel distortion is called positive, and the sulk - negative. In classical photos, distortion is a marriage, so photographers are trying to prevent her appearance. In wide-angle lenses embed special corrective lenses in order to avoid such an effect.

However, if the distortion works on the tasks of the photographer, it can become an interesting artistic technique, the way to get unusual, bright pictures.

Fish eye (lens) characteristics

The main difference of this lens is the viewing angle. It is at least 180 degrees, so one frame becomes possible to fit half of the space. It is believed that the fish just sees items, why and the name has passed - "the effect of" fisheye ".

The following characteristic is a focal length. It is short, 6-15 mm.

Blends for such lenses are very small or not at all. This is due to the fact that due to the huge angle of viewing the lens of Blend, it can get into the frame. Also, the traditional installation of the light filter on Fishai is impossible.

Lens varieties

Two types are isolated: circular and diagonal. The circular "fisheye" (lens) gives a circular perspective, but the image does not fill the frame completely. At the edges of the frame on the full-frame chamber, it can be seen that the part of the image is missing and replaced with black corners. This type of lens is used only in the photo applied directions (for example, meteorology).

The diagonal type is different called full-frame. An image from such a lens fills the entire frame of the whole, this is achieved by a small reduction in the viewing angle. This type of lens is both the most popular.

The history of the lens

The term "fish eye" introduced an American physicist Robert Wilms Wood, who was the first to think about how a fish could see the world around. He put forward assumptions and conducted an experiment with the participation of a hermetic drawer filled with water and containing a small hole. The first photos taken with this box saw the light in 1906.

Lens "Fish Eye" began to be used since the 20s, it was used in meteorology to shoot clouds. Also, lenses were needed for astronomical surveys.

To date, there are already dozens of similar lenses, the viewing angle of individual models reaches 220 degrees, and the scope of their use has significantly expanded. In addition to the lens, there is also a fisheye camera. These are panoramic models with a viewing angle of 360 degrees.

In the USSR, the first photographer who used such a lens for his work was Borodulin L. A., Master of Sport Photography.

Why use the effect of "fisheye"?

The lenses with such an effect are often used to shoot extreme sports, it makes it possible to show not only the athlete itself in the frame, but also the whole trick is completely. At the same time you can shoot from a short distance.

The lens is good for shooting spherical panoramas. You can find the use of such a lens for interior shooting, especially if we are talking about small areas and narrow spaces (corridors, bathrooms). If you need to create a virtual 3D panorama, also not to do without Fishai.

To achieve the comedy effect when shooting portraits of people or animals, such lenses also use. Funny and bright shots are obtained.

If we generalize, this lens makes it possible to see usual things from an unusual point of view, and it may be very interesting. You can shoot architecture, landscape, trees with unusual angles. Strange snapshots cause a very lively and emotional reaction in the audience.

You can also shoot people, for this person you need to place in the center of the frame and depart from it away. The human figure will be in this full growth, small size and without distortion, but the space around the shooting object is very interesting to sparkles.

How to choose the lens

If you decide that you need a lens "fishing eye", then here are some tips that will help avoid disappointment after purchase.

Take into account the size of the matrix of your camera, acquiring the lens. For a full-frame camera there will be enough focal length of 15-16 mm, for a camera with a crop-matrix you will need a lens with focus distance 8-11 mm.

Of the existing two types of lenses - diagonal and circular - the first is most preferable. Examples suitable lenses: Canon EF 15 mm F / 2.8 FISH-EYE, MS Zenitar-m.

This lens is unlikely to become your main work lens, too narrow the framework of its use. But to replenish the arsenal of the means of artistic expressiveness, he is really good and worthy of taking his place in the bag of the photographer.

Fisheye lens is not often considered as an important tool among professional landscaped and urban landscape players. People see them not much more than the effect of a wide angle with a specific distortion. Many do not even like this species lenses because of this distortion.

You can change your opinion, having worked with fisheye optics for a while. For example, the lens SAMYANG 12MM F / 2.8 FISHEYE gives a lot of new opportunities, and the lavender is fun with it.

Install the fisheye optics and explore the environment through the viewfinder. You will see the world completely in a new way, which will open space for creativity. And that's not all. Fish eye can also be very useful in obtaining pictures that usually require a lot of effort or it is impossible to do with other optics. Think about pictures from the height, the code is distorted by the lines actually gives the point of the image.

Here are a few reasons why you should consider using ultra-wide-organized lenses.

1 distortion

Distortion can be annoying. But it is not necessary to treat it so critical. Use the distortion of the superwater lens in your favor. Find the scenes in which the effect of a fish eye adds something interesting. Try using this effect to work with leading lines.

The next frame of Hong Kong with slightly distorted buildings works well in combination with curved road shapes:

2 The ability to align

Sometimes lenses of fish eye can be used as optics for filming a wide angle. Locating the horizon in the middle, as a rule, you will get an almost direct line. Some instruments in editors will help straighten distortion to get super wide-angle images with straight lines.

3 Use with round shapes

Fish eye usually twists straight lines. So, if you take pictures of rounded shapes, curvature becomes less noticeable. Try to photograph the pipes, round stairs, intersection, etc.

Curved horizon completes this frame by making a full circle.

4 Rackers

You can get incredible lines by lifting the lens up. Using different walle tilt can be obtained incredible frames.

5 Great for backstage

This optics is good for shooting what is happening behind the scenes during photo sessions, video, hiking and trips, etc.

6 Creative portraits

Try to make wide-angle selfie or portraits. Do not place people too close to the edge, otherwise you will get a lot of distortion.

7 Creativity

Fish eye can create pictures that would not be possible with normal lenses. Try to keep the superwatch lens on the camera for a longer period of time, and learn your environment through the viewfinder. You will be amazed at how interesting can be seen on the camera screen compared to what you see with your own eyes.

The use of wide-angle lenses opens the whole world of opportunities. Show a creative approach and having fun!

The lenses are separated along the corner of the review. In addition, each type of optics can be divided into more accurate categories. Wide-angle optics can be divided into superwatch and fishey (fisheye). When developing wide-angle optics, developers are trying to fix all distortions as much as possible. In the case of fish eye, everything else. These lenses have the strongest distortion.

How can a photographer use a distortion of Fishai-lens?

AT real life Lines of buildings are straight. The wide-angle lens tried to make them on the photo and it turned out. Fisheye's eyes did not heightely and bent all the lines as it is more convenient. Such is his design. The center of the frame Fisha retains the lines lines. They are spinning only to the edge of the image.

Fishay is great for art photography. It is often used in architectural and landscape photo. Removing people with such optics a little comic. Persons and body proportions are very distorted.

If your goal is to transfer the maximum realism in the photo, then the fish eye will not suit you. Now the virtual reality systems are increasingly distributed and the lens form can be useful for shooting spherical panoramas. Creating curves of lines at the frame edge is a fee for a very wide viewing angle. Fish may accommodate the image almost 180 degrees from all sides.

Fishi are different. There are optics, which provides an angle of view 180 of the Gadus diagonally. Some lenses create a round image that accommodates an overview of 180 degrees in all directions, but these lenses are rarely found, as they create very unusual round images on a rectangular sensor. Because of this corners are fermented.

If you have a camera with an APS-C matrix, then you need to take Fishaly for this sensor format. If you use optics from the full-frame camera, then due to the crop factor, the beauty of a wide viewing angle will be lost. Fishing eye lenses allow you to create images with a very unusual geometry. Smooth squares are distorted, and buildings, poles and trees are bizarrely twist. If you change the angle of inclination of the camera, then you can get completely new types of familiar places.

Conventional wide-angle lenses create smooth horizon lines and verticals. Such pictures look very familiar.

Do not think that buying a fish eye will allow you to experiment infinitely. In fact, the functionality of such optics is limited. She will do all your footage the same. Even when changing the plot, they will all look like each other, so such a shot need to be dosed and create really interesting stories.

"Fish eye" - the effect of bulging in the central part of the picture. It is achieved by the use of special lenses or manipulations in the photo editors, in our case - in Photoshop. It is also worth noting that some modern action cameras create such an effect without any additional actions.

First, choose the original image for the lesson. Today we will work with a snapshot of one of the districts of Tokyo.

Image distortion

The effect of fish eye is created by just a few actions.

After pressing, I will see this, already distorted, frame with the only central point. By moving this point in the vertical plane, you can change the strength of image distortion. If the effect is satisfied, then press the key Input on keyboard.

It would be possible to stop at this, but the best solution will still slightly emphasize the central part of the photo and toned it.

Adding vignette

As a result, we get this vignette:

Toning

Toning, although it is not a mandatory step, but give a picture more mysteriousness.

 

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