Two propane tanks on the front of an RV, one is full, one is empty.
Which one is full?
So what’s the all important conditons. Ambiant temp. Direct sun? How long? Color and condition of the tanks?
One thing I’ve learned about thermal shots is that knowing the conditions is essential. What seems obvious can turn out not to be after you can see the whole picture.
But… Propane gas does not absorb heat anywhere as easily as liquid propane. Assuming the same storage conditons (ie one didn’t just get filled) So as my quess I’d say the warmer (redder) tank is empty or near so as there is no cooler liquid propane to absorb the heat. The cooler tank (lighter red shade) is the one with propane.
Since I have a full one and empty one available tomorrow I’ll run an experiment.
No sun, taken around 8pm in the shade, white, newer tanks sitting for days nothing unusual. Outside air temp around 75 deg I think.
The one on the right is Full—
The one that weighs the most. 
I concur.
I concur as well,
You got a camera?!
I will say – Hotter one is the full tank
Both had sun, now in shade, liquid slower to transfer heat
yep, left one is full, right one empty
they had a white plastic cover that fit over both and were in the sun only a short period in late afternoon.
Do you think this rain barrel has water?
Maybe 2 inches
This one’s too easy…
More like 4" Wayne
LOL Mario i could never judge Measurement