kingofnobbys
BD.org Sicko
Very common for a gun to be recommended to measure temperatures in a viv , BUT likely the temperature gun is :
>>> not being used correctly ( if reading high you may be measuring ONLY surface temperatures and be introducing a systematic error due to the gun seeing the reflection of the basking globe on a "reflective" surface , an error called a specular error.
>>> incorrect emissivity setting programmed into the gun for the surface being measured by the , if the surface actually has a higher emissivity , the temperature measurement will be too low, and conversely if the emissivity of the surface is actually lower, the temperature will be too high :
and
>>> very common for amateurs to shoot the temperature from TOO FAR AWAY , it is very important that the area you to measure FILLS the measurement spot , if you are too far away , the gun will see & measure background too , which may be either a lot cooler (most likely in a viv) or a lot hotter , and it will simply indicate the average. SO if the gun has a spot specification of 12:1 , this means the spot is 1 inch in diameter at 12 inches from the surface, so your spot needs be larger than the measurement spot ( you come closer ) to ensure the spot is filled.
The digital thermometer is the measurement I'd take as being reliable and accurate provided it's had time to reach thermal equilibrium and is either
>> in physical contact the surface if you want to measure the surface temperature
>> suspended in the media (air) if you want only radiant heat and air temperature.
>>> not being used correctly ( if reading high you may be measuring ONLY surface temperatures and be introducing a systematic error due to the gun seeing the reflection of the basking globe on a "reflective" surface , an error called a specular error.
>>> incorrect emissivity setting programmed into the gun for the surface being measured by the , if the surface actually has a higher emissivity , the temperature measurement will be too low, and conversely if the emissivity of the surface is actually lower, the temperature will be too high :
and
>>> very common for amateurs to shoot the temperature from TOO FAR AWAY , it is very important that the area you to measure FILLS the measurement spot , if you are too far away , the gun will see & measure background too , which may be either a lot cooler (most likely in a viv) or a lot hotter , and it will simply indicate the average. SO if the gun has a spot specification of 12:1 , this means the spot is 1 inch in diameter at 12 inches from the surface, so your spot needs be larger than the measurement spot ( you come closer ) to ensure the spot is filled.
The digital thermometer is the measurement I'd take as being reliable and accurate provided it's had time to reach thermal equilibrium and is either
>> in physical contact the surface if you want to measure the surface temperature
>> suspended in the media (air) if you want only radiant heat and air temperature.