§   Resolution

The resolution defines the detail that you will see, no matter in analog or digital. The main difference between digital and analog resolution, is on the resolution it can reach. The maximum resolution of NTSC and PAL, in analog cameras, after the video signal has been digitized in a DVR or a video server, is 400,000 pixels (704x576 = 405,504). 400,000 equal 0.4 Megapixel

Due to PAL/NTSC standard, analog resolution is restricted to 0.3 megapixel, while digital can reach to 5 megapixel or even more.

In addition, the resolution of analog and digital is measured in different way:

Analog resolution

 “TV lines” refers to the number of discernable horizontal or vertical lines on the screen. Analog security cameras are measured in Analog TV Lines, and most of them have between 420 and 580. The higher number of TV Lines, the more information captured. These types of cameras connect to a security DVR or CCTV VCR via coaxial video cable.

Digital resolution

A pixel is the smallest element of a digital image. We have all zoomed too far into a picture from a website and seen the image go from clear to a bunch of colored squares – each one of those squares is an individual pixel. A megapixel (MP) is 1 million pixels, and is a specific measurement for digital resolution that encompasses the area of the output video.
Example: If a camera outputs a signal that is 1280×1024 pixels, it is shooting at a megapixel resolution of 1280 x 1024 = 1,310,720 pixels = 1.3 Megapixels (MP).