by berkinet on Sat Aug 25, 2012 12:10 pm
Infrared thermometers tend to not be all that accurate (often plus/minus 5 degrees Celsius), especially the inexpensive ones. They are fine for checking for relative change, and things like wood burning ovens where "close" is good enough. Depending on your needs, that might, or might not, be ok for coffee roasting.
Also, accuracy is a function of distance. The measured area expands as it gets farther from the sensor. So, if you are sufficiently far away, you might be measuring more area than you think.
Finally, the laser is just a pointer so you can see where you are aiming. It has nothing to do with the actual temperature measurement.