Having an optical viewfinder makes framing and composing the shots easy and you will find one in almost all high-end digital cameras. However, some of the low cost models might come with an LCD screen only and this is likely to present some of the following problems:
The LCD-screens consume a lot of battery power and having the screen on at all times will inevitably result in less photos taken per battery charge.
The vast majority of the cheaper digital cameras come with LCD monitors that are difficult to read in bright light. In some of the compact digital cameras, the screens might come with a backlight that can be turned on when the lighting conditions are unfavorable, but this again will result in the battery being drained much quicker.
Optical viewfinders make composing an action shot much easier - holding the camera close to the eye and following a fast moving subject will most certainly produce better results than when trying to achieve the same by using a monitor as a viewfinder.
When using a screen, you can accidentally cover a portion of the shot with your fingers. Some of the digital cameras come with LCD-screens that occupy greater portion of the back of the camera and in the case of the touch screens they can occupy the entire rear side. Larger LCD screen is likely to provide better preview, but covering at least a portion of the screen with a finger might result in poorer shot.
The LCD screens provide fewer details. The vast majority of the compact digital cameras come with screens that are anywhere from 2'' to 3.5'' in diagonal and even if they come with high resolution, the human eye looking through a viewfinder is capable of seeing far more details.
Touch Screen Lcd
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