I don't calibrate either. I can feel through the holes, how humid it feels coming up through there. I know, sounds wrong. When I am turning eggs, I just go by how they feel and watch what the thermometer is saying, then go from there. I know how I like them to feel for incubation.
No one try this at home until you have incubated for a few years..lol...
I'm w/ you on feeling the eggs for temp. , in fact I've been making a point of it after all the bad thermometer readings last winter/spring I started really focusing on what do the eggs feel like. I can reach in my LG w/o opening it much at all & touch several eggs (I have very small hands & extreamly temp. sensitive fingers, which is a pain for any other thing but testing incubating egg temps.) I now trust my temp touch of the eggs more than anything else, same for feel of humidity in the bator. I would say most ppl would not want to try that, but if you have annoyingly sensitive skin then it might be your super power too ;>
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SO I'm trying to get to LOCKDOWN,
but
Our weather has gone way cold today & the hatcher is taking forever to be ready

I pulled the plug on the turner w/ the eggs at a level point when I caught them that way this am, (I have other eggs in there that need the turner b/f much longer but I'm favoring my NYDH shipped eggs over the barnyard test eggs right now).
I set Dec11, 6pm local -- so far no wabbles or peeping which given the delay in moving to the hatcher is good atm,
& I'm trying really hard not to take it as bad news re: those crazy shipped air cells...
AGAIN, GOOD LUCK , esp. to the folks w/ the wrong egg pipped eggs, !! & for everyone waiting for signs of life, I'm feelin' it w/ you...