Digital signage needs to be visible at all times under all conditions for you to get your messages to your consumers or clients across successfully, so getting the brightness level of your displays right is critical. Are they going to be exposed to bright sunlight or sudden changes in light levels? Are they competing with other sources of illumination? For a digital image to be successfully seen or read it must have adequate levels of brightness and contrast for easy viewing. You need to factor this in when choosing your digital displays and set them up correctly from day one.
This is a quick guide to make sure that the displays you are considering purchasing for a particular area will be up to the job. First, let’s go over the basics of how brightness is measured.
ANSI lumens vs Nits
There are various measures of brightness out there, but the one most commonly used to describe digital display brightness is ‘Nits’. You will also see brightness measured in ANSI lumens. There is a difference, ANSI lumen is often used when describing the output of video projectors and is a general term describing light output, while Nits measure how much light a TV screen sends to your eyes from a particular angle (its luminance). 1 Nit represents more light than 1 ANSI lumen.
A Nit (also referred to as cd/m2) is a standardised amount of light output equal to one candela per square meter. A common wax candle emits the luminous intensity of roughly one candela. To give you some examples, non-HDR TVs usually have the capability to output 100 to 200 Nits, the average indoor LCD will feature a brightness measurement of 200 to 350 Nits, while HDR-compatible TVs may have the ability to output 400 to 2,500 Nits.
Choosing your brightness level
So what should you be looking to invest in for your display? If you are in a shaded indoor or outdoor area, then you need a display over 350 Nits, for brighter areas you will need something closer to 700 Nits, and for full sunshine you need something offering 1,500 Nits or over.