Table of contents:
- Define distortion
- Types of distortion
- Distortion when shooting
- Correction of distortion during processing
- Intentional distortion
Distortion is an error or error in the combination of optical elements, during which the linear magnification factor changes over the field of view of the lens.
Distortion is translated from Latin as "curvature". With distortion, there is a violation of the similarity between the object and its visual image. Distortion is an error. It can be corrected at the stage of selecting an optical system when choosing lenses or when editing a photo in a PC. Distortion is a noticeable phenomenon if there are straight horizontal or vertical lines in the frame. With distortion, straight lines become curved outward or into the image. It is pronounced when photographing architectural buildings, trees, poles, and other objects.
Types of distortion
Distortion occurs in two types - it is barrel-shaped and pillow-shaped.
Barrel or bulge distortion is distinguished by the fact that the curve of the line is directed outward, while the object becomes convex, and this is very noticeable relative to the edges of the image.
As for pincushion or concave distortion, it is distinguished by a bend in the line closer to the center of the frame, that is, the lines appear concaveinside the image.
Also, barrel distortion is called positive, and pincushion distortion is negative.
Distortion when shooting
The reason for camera distortion may lie in the lens of your camera. If it is more understandable to disclose this, then it can be noted that when using cheap lenses, the quality of which can be doubted, the image is distorted. This is most often the case with lenses that are called "Zoom Lens", they have a variable focal length, which is why distortion occurs.
The second reason lies in the moment of photographing - this is the convergence of lines that are parallel to each other in an inclined position, or when the photographer himself leans. This mostly happens when shooting tall buildings from a low angle.
To avoid distortion when shooting, you can use a few simple rules:
- purchase a quality lens, preferably a wide-angle one;
- move away from the object, and when photographing bring it closer.
If these two simple rules did not help, then photo editors can solve this problem. This is pretty easy to do.
Correction of distortion during processing
If the distortion is subtle, then it can be removed when downloading the Adobe Camera Raw tools using the Adobe Lens Profile Downloader. Open the Adobe Camera Raw program, click on the picture you want to edit. Go to the Lens Corrections tab and activate the lens profile by settingtick Enable Lens Profile Corrections.
First you need to open a photo in this program and go to the Lens Corrections section, then select Manual, there you will see such positions as distortion, vertical, rotate and others. It is necessary to move the distortion slider to minus as much as necessary to completely eliminate distortion.
"But how to fix distortion in Photoshop?" - you ask. Yes, easy! First, open the image in Adobe Photoshop, then the Filters tab and select Lens Correctons. You will open a window, and you must open the Custom tab, then move the characteristic slider called Remove Distortion to a positive value until the distortion is completely corrected.
Photographers do not always consider distortion a photographic flaw, some try to make it intentionally with a lens or when processing a photo in an editor.
As for the lens, "Fisheye" or as it is also called "Fishai" is very common. This is a type of so-called ultra wide-angle lens that has a convex front lens at 180 degrees, which is what causes distortion in the pictures. There are two types of fisheye lenses: circular and diagonal. The circular lens is most commonly used in meteorology to take photographs of the sky. The diagonal lens is the most common among photographers. We even know the name of the first photographer who first usedthis type. This is Lev Abramovich Borodulin, who is a well-known Soviet and Israeli sports photographer.
There are a number of other lenses, but they are all aimed at creating image distortion, such devices can be found in Nikon, Canon, and other camera companies.
You can make distortion in "Photoshop" on purpose, for this you need to open the desired image, select it and go to the "Editing" tab, then you need to select the "Transform" function, a number of additional functions will appear there, you should select "Deformation ". Your image will be placed on the grid, which is where you need to work. Drag the image the way you want.
Despite the fact that distortion is most often perceived in a negative way, in some cases this effect is used intentionally to focus attention on a particular moment or part of an object. This effect has been used in the photo industry for a long time, but it has become very popular relatively recently.
Distortion is a photographer's way of expressing himself, an opportunity to show his individuality. It gives the picture a special glamor and specificity. Today, an increasing number of photographers around the world are starting to work closely with this effect and take full advantage of the possibilities that distortion gives. Of course, not all professionals, andordinary people like photos taken with this effect, but there is no point in denying the fact that interest in distortion has increased greatly in recent years, since it is obvious.