Normally we heard, buy higher pixel, will have better quality. However when we buy that camera, the result is differ. For example when we buy Samsung S6 and iphone 6 is it have a different. In CCTV camera also the same.
Higher Resolution = Higher Quality picture = Higher Storage Needed = Higher Money
Here is the example
320 x 400 pixel (higher quality)
if we turn to the lowest quality the picture will be different. Remember! The lens of the CCTV is normally fixed. You need to zoom for a better viewing. Bottom picture show the medium quality.
100 X 125 pixel (Medium Quality)
50 x 62 pixel (Lowest Quality)
Pixel determine the quality of the picture. The lens of the camera normally fixed. In CCTV, highest resolution may result in good quality picture. Low quality may result in problematic because the picture may unclear if the view is far from the camera. Choose your camera wisely.