Certain models have various apparent temperature color alarms.
This function can often lead to some confusion.
If you are showing no thermal image but you can see a visible light image you may have turned on your color alarms.
The high temperature color alarm shows a full visible image and only shows infrared information on objects or areas that are above the set apparent temperature alarm level.
The low-temperature/dew point color alarm shows a full visible image and only shows infrared information on objects or areas that are below the set apparent temperature/dew point color alarm level.
The user must manually find and set these parameters. Certain models also display color isotherms, or infrared information, inside or outside of a set of both high and low limits.