Digital single lens reflex camera viewfinders come with various levels of enlargement and brightness. Some people, however, may find the size of the image in the viewfinder too small for comfortable viewing. There are a variety of eyecups that can be purchased to address these issues.
An eyecup magnifier enlarges the size of the image projected in the viewfinder, while making it slightly dimmer. A larger view can be useful for photographers with bad eyesight or those who enjoy manual focusing.
Eyecup magnifiers replace the eyecup provided with the camera. They can be installed in seconds.
Dioptric correction lenses
Dioptric correction lenses correct vision and improve a photographer’s ability to focus and compose a photograph while looking through a viewfinder. Correction lenses are purchased with an eyecup that attaches to a camera’s eyepiece.
Diopter lenses come in a variety of strengths for near- and far-sightedness, for example -2.0, +3.0. An optician can tell you the strength needed.
The perimeter of the eyecup is made of soft rubber material, which helps keep out extraneous light and makes it more comfortable when holding the viewfinder against the face.
Eyecup magnifiers and diopter correction lenses can be purchased from the camera manufacturer, or ordered at most camera stores.