The rock temp is what you should be going by! Also, for an adult dragon 100*F is better than 110-120. 110 is used for babies who's metabolism is much higher. Adults don't need it that hot. If the basking rock is too hot, they can literally cook their insides & burn their skin.
The best way to get an accurate basking temp is with a I.R. Temp. Gun. You just aim it at what ever you want to measure.
Or you can use a digital in/out thermometer. You put it to "out" and run the probe cable in the cage & use a rubberband or something to hold the probe on the surface of the basking spot.
To get the basking temp. you put it at the closest point of the object (what ever is used as a basking surface) to the bulb.
The air around the object may be 90* but the surface could be 130*. That would not be good,, so definitely measure the surface.
I hope that helps.
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Joel R
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