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Can a camera with a separate viewfinder be equipped with an interchangeable lens?

for exchange ?

An interchangeable lens facility is needed on a camera with a complex viewfinder, which is why this feature is only found on more expensive cameras. A simple solution to this situation is to mount separate viewfinders on an accessory housing, but these add to the situation of parallax error, which can be dangerous in the case of a telephoto lens with a narrow acceptance angle. Interchangeable lenses partner with the camera's internal field finder for precise focusing operation

Are there any other disadvantages to separate viewfinders?

The main problem is that many of these viewfinders show a greatly reduced image of the field, rarely larger than normal 0.6 x -0.5 in size.

While we find that most SLR cameras show a normal size of 0.8 x, that is the lens with which the viewfinders are installed.

What is a reflex viewfinder?

The viewfinder in a reflex camera shows us the overall image that will actually appear on the film, whether it is a single-lens or double-lens reflex camera. In the case of a single-lens reflex camera, we find that there is an articulated mirror located behind the lens that reflects the image on a focus screen or focal adjustment Figure 160, and this is usually seen through a five-pointed prism Figure 164 that reverses the visible image so that it becomes in a rounded and upright position in the appropriate manner. The mirror deviates from the path of light before exposure to it. This means: the viewfinder blackens for a moment during exposure to pan light

A dual lens reflex camera is actually two cameras stacked on top of each other. The lower camera contains the pick-up lens and the film chamber, while the upper lens contains a similar lens, a reflective mirror, and a vision screen (Fig. 168).

The vision screen is exactly the same distance as the film from the lens. So if the focus is sharp on the image of the shot, the image on the film will be as well. By designing appropriate optics and shutters, the image shot on an SLR camera not only shows the area of ​​the image that will be recorded on film (in fact most SLRs show an average of 15-98% of field) but the image will also be almost life-size with a standard lens.

Figure (16)

Reflex viewfinder - : - pentaprism type at eye level; B - double-lens reflex camera; C Single-lens reflex camera at waist level.

What is the instant bounce mirror?

The instant rebound woman is a feature or feature of the single-lens reflex camera, as it returns to the vision position immediately after the end of the exposure process. All types of SLR cameras are now equipped with this device, but it was at one time known and common for the viewfinder to remain obscured until the film had been rewound until the next exposure. Some photographers consider this property to be a vehicle
Is the focus screen important?

The focus screen installed in reflex cameras must fulfill two main functions, it must show the visible image by the lens that will be recorded on the film, and it must provide a sufficiently clear and bright image for it to be precisely focused. In addition, the focus screen It must be precisely located in order for the installation to be accurate. It must also be suitable for use with different lenses and accessories and for a variety of different subjects. Each of these standards requires various features that must be built into the monitor. Fixed screens combine the characteristics of all required features. A fixed screen usually includes two focusing aids - a segmented image rangefinder and a fine-prism collar, or center spot in a fine-prism with a ground collar (Fig. The screen also includes a Fresnel lens to ensure a straight-angled image, free from central hot spots in the screen.

How does the viewfinder work at eye level?

The image seen from above on a focusing screen is reversed left to right, but right up (because it is mirrored). If the camera is on its side, the image is upside down. For looking at eye level, a pentagonal prism (or a surface prism) reflects the image on the eyepiece, reversing it laterally at the same time, and thus the view becomes clearly direct through the camera for horizontal or vertical images with