The viewfinder is the window through which the photographer looks at the world. At least when it’s filming. There are viewfinders that really are just a hole in the body, covered with glass, there are more complex designs with mirrors. There are those who only pretend that they are a hole, when in fact they are a screen. Read more about different viewfinders in this text.
The most common optical viewfinder today. The design of the viewfinder is almost the same as it was in the days of film DSLRs. The light passes through the camera lens and hits the mirror (1). Most of the light is reflected from the mirror, enters the pentaprism (3) and enters the photographer’s eye through the eyepiece (2). Well, a small part of the light beam passes through a translucent area in the center of the mirrors (1), and with the help of a small movable mirror it hits the autofocus sensors (5).
The matrix (4) and the shutter are behind the mirror, and the light does not fall on them. When the photographer presses the shutter, in a reflex camera, the mirror first folds up, making way for the light, and then the shutter opens and the light hits the matrix.
Since the light goes through the lens, we see the same thing that the matrix will see. If the camera is too far out of focus, the picture in the viewfinder will be blurry. If a filter is installed on the lens, you see what effect it gives.
Looking into the viewfinder of the SLR, we will see something like this picture. In the center, the focus area and the autofocus sensors available for selection are visible, the active sensor is highlighted, the rest are usually not visible. At the bottom is a line with shooting parameters. At a minimum, these are shutter speed, aperture, ISO value and exposure compensation. In more advanced cameras, you can see the shooting mode (PASM), metering mode, the type of file saved (RAW or Jpeg) and the number of photos that can be taken before the memory card is full.
A grid can be brought into the field of view to facilitate framing, and in some older DSLRs, a level showing the camera’s deviation from the horizontal and vertical.
The size of the reflex viewfinder directly depends on the size of the camera (and the matrix in it). In a large full-frame DSLR, the viewfinder will be large and bright, but in a small cropped camera it will be noticeably smaller.
The disadvantages of optical viewfinders include:
- for a person who is used to seeing a finished picture on the screen of a smartphone or compact camera, a reflex viewfinder may be unusual. Even if you set the camera incorrectly and the final picture is underexposed or overexposed, this will not affect the image in the viewfinder in any way;
- This viewfinder cannot be used for movie shooting. The mirror either directs the light into the eyepiece or blocks it so that the light hits the matrix;
- noise. The clapping of the rising and falling mirror does not allow you to shoot silently. Shooting speed limit. Before taking each shot, a camera with a reflex viewfinder must raise the mirror, and then lower it into place. As a result, DSLRs reach speeds of 12–14 frames per second, while mirrorless cameras easily accelerate to 20–30 frames per second.
These viewfinders are most commonly found on advanced compact cameras such as Canon’s G‑series. There are also some old film cameras.
A telescopic viewfinder is a simple design of several lenses that allows you to roughly see the boundaries of the frame.
It doesn’t have many advantages. Firstly, it allows you to build a frame when it is difficult to see something on the camera screen due to the bright sun. Secondly, it does not require power, and if you turn off the screen and use only the viewfinder, the battery will last longer.
But there are many cons. The viewfinder is small, as is the image in it. In most cases, no additional information is visible in the viewfinder. And if the lens moves forward when zooming, it will block the viewfinder field of view.
If your camera has a rangefinder viewfinder, then either you shoot with your grandfather’s film FED, or with a modern and very expensive Leica digital camera.
The picture in such a viewfinder will not show you what the camera sees. By attaching a polarizing filter to your camera, you won’t see any change in the viewfinder. And even if you forgot to remove the lens cap, you will only know about it when you see the finished picture.
In the field of view of the viewfinder, frames are visible — from them you can roughly guess what the camera sees. When you install a native lens, the frame corresponding to its focal length is automatically highlighted. As you can see from the photo, for a lens with a focal length of 75 mm or more, this frame is quite small, and it is difficult to work with telephoto lenses on a camera with such a viewfinder.
An electronic viewfinder looks exactly like a reflex viewfinder — a window through which the photographer sees the frame. In fact, this is a small screen plus eyepiece lenses. This means that you can display exactly the same information on it as on the main screen of the camera. Such viewfinders are used in many mirrorless and some advanced compact cameras.
The main advantages of the electronic viewfinder include the fact that the picture in such a viewfinder is immediately displayed taking into account all the camera settings. And immediately shows how the finished photo will look like. We changed the white balance or exposure — and these changes immediately became visible. This means that even an inexperienced photographer will easily get a correctly exposed frame with beautiful colors and make fewer mistakes.
In addition, a grid can be displayed in the electronic viewfinder to facilitate framing, level, and a histogram can be displayed. It will make life easier for those who use manual focus when shooting video or like to shoot with old manual lenses — the included focus peaking will highlight sharp areas.
Through such a viewfinder, you can shoot video, view the footage, and in some cameras even work with the menu.
Since the design of the electronic viewfinder does not require a bulky system of mirrors and prisms, it can be made inclined or even removable.
Mirrorless cameras have an optical viewfinder emulation mode. This is useful when you are working with pulsed light. For example, if you are shooting in a photo studio, the image in the electronic viewfinder will probably be too dark, since the right amount of light will appear only at the moment the studio flashes are fired. When you turn on the emulation mode, the exposure settings no longer affect the picture, and you will see the scene in the viewfinder close to how it is seen by the naked eye.
The electronic viewfinder also has its downsides. First, the electronic viewfinder is based on a screen made up of individual pixels. And when electronic viewfinders first appeared, there were few of these pixels, and they were quite large. And looking into such a viewfinder with a resolution of 0.3 megapixels (640x480 px), the photographer saw a mosaic of pixels instead of a smooth image. It was really inconvenient to use such a viewfinder.
But modern cameras have a much higher viewfinder resolution (for example, not the newest and quite popular Sony A7 III — 2.3 MP, Lumix S1 — 5.7 MP, Nikon Z 7 — 3.7 MP, Fujifilm X‑T4 — 3 .7 megapixels, while the latest Sony A1 has as much as 9.44 megapixels). In cameras of the latest generations, the picture in the viewfinder is clear and beautiful, and individual pixels are not visible.
The next drawback is the viewfinder lag, the image in it is a fraction of a second behind what is happening. With the latest cameras, this delay is very small and almost imperceptible, but still not zero.
And the last minus, which is the most difficult to get rid of, is constant power consumption. In order for a picture to be displayed in the viewfinder, the camera matrix, processor and viewfinder screen must work. All this requires energy (and the higher the resolution of the viewfinder, the more). Therefore, to conserve battery, mirrorless cameras should be turned off when not in use.
The viewfinder is part of the design of the camera. What kind of viewfinder you have determines the type of camera. Most often, optical viewfinders can be found in DSLRs and rangefinders, and electronic ones in mirrorless and superzooms. There is an exception — Sony had a line of DSLRs with a translucent mirror. For example, Sony A99 Mark II.
In fact, asking which viewfinder you are comfortable using can tell you which type of camera is best for you. If you want to immediately see the picture the way the finished picture will be, then your option is mirrorless. If you do not trust the screen and want to look at the picture through mirrors, then your option is a DSLR.