Things You May or May Not Know About Video Quality

Does a high number of pixels guarantee better video quality?
The answer may surprise you.

Video quality is affected by many factors including the type of lens, type of image sensor, signal processor and compression. It is very easy to process low resolution images. High resolution images require a lot more computing power and very complex formulas to properly apply image enhancements to the video (i.e. white balance, color correction, auto focus) especially under shifting lighting conditions. The higher the sensor resolution, the more difficult it is to adjust the lens focus and the smaller the physical dimensions are for each pixel; which makes each pixel more vulnerable to optical bending. Multi-Megapixel cameras produce large amounts of data and it is challenging to compress the data to reduce the file size as much as possible without significant losses in the video’s quality.

The image quality is determined by the number of television lines (TVL); TVL is defined as the maximum number of alternating light and dark lines that can be resolved in an image. Until you get to 640x 480 VGA resolution, the number of pixels and the TVL number track each other pretty closely, since even relatively low cost lenses work pretty good at those resolutions. When you start getting up into the 2-5 megapixel camera range, you really start to see the effects of lower quality lenses on the image sharpness, especially at the edges of the image.

So basically to get the best image possible you need a camera with a very high TVL number – not the highest pixel number.

~TeCHS