Why does a SLR camera look blurred when taking pictures?

The radian of the viewfinder is not adjusted well, and the diopter, that is, myopia, is not adjusted well.

The reason why there is parallax is because it is blurred when taking pictures. Because the camera lens and viewfinder look at the subject from different positions, there will be some differences in the scenery they see. The optical viewfinder should be as close to the center of the lens optical axis as possible to reduce the parallax of the viewfinder.

The size of the light entrance hole in the viewfinder determines the clarity of the image. For users who wear glasses, it is more important to have a relatively large light entrance hole, because glasses will make their eyes farther away from the viewfinder and can't accurately view. However, only people with myopia and hyperopia can perform refractive adjustment. For photographers with normal vision, refractive adjustment is meaningless.

Extended data:

The viewfinder has two main indicators: viewfinder magnification (viewfinder magnification for short) and viewfinder range.

The magnification of the viewfinder refers to the ratio of observing the opening angle of the subject to the eyes through the viewfinder to directly observing the opening angle of the subject to the eyes, that is, the ratio of the size of the subject seen through the viewfinder to the size of the subject directly seen with the eyes.

The magnification of framing is large, the viewing angle is small, and the scenery seen during framing is close to the original object, with strong sense of reality; The framing magnification is small and the viewing angle is large, so it is easy to see the panorama when framing. If the magnification is too small, it is difficult to observe the details of the object, which is not conducive to composition and focusing, and there is a great difference between the object and the image, which makes it very uncomfortable to take pictures. The magnification is generally less than 1X, mostly between 0.75 and 0.95 times. ..

Field of view refers to the ratio of the scene range seen through the viewfinder to the scene range shot by the bottom film, expressed as a percentage. Generally, the picture seen from the viewfinder is not completely the shot picture, but always smaller than the shot picture, generally 90% ~ 100%. Therefore, SLR only basically avoids parallax, and only the framing range of 100% can be called no framing parallax.

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