What is the position of thermometer should be shed the most appropriate?

Thermometer, also called greenhouse thermometer, can be seen everywhere in our daily life, is mainly used for measurement of temperature in the greenhouse. So it should be in what position the most appropriate? We will with our MMG - today 3 the thermometer, for example, what the thermometer should be put in greenhouses where the most appropriate. Model: MMG - 3 types: maximum and minimum thermometer, greenhouse structure: the thermometer can flip eaves, circular button material: beige ABS shell shape size: 22 * 13 cm temperature range: - 40 - 50 c, red and black single calibration accuracy: + / - 1 c if put the thermometer in direct sunlight, to measure the surface temperature of the thermometer, because sunlight surface thermometer is heated, the temperature is generally higher than the surrounding temperature, the measurement of the thermometer features determines the measurement results of this case is a temperature rather than the surrounding air temperature on the surface of the thermometer. Poorly ventilated place because heat is inadequate, the air temperature can only reflect the status of local temperature, and temperature have the obvious difference. So the thermometer should be placed in a cool ventilated place, which ensures that the measured temperature of the surrounding.