THERMAL . . WARM - - -> EXTREME COLD . . ??

pruhdlr

Cantonment,Fla.
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I have a buddy up in Maine that is going to buy thermal. Most likely a <$5000 unit.
He has a piece of rural property where he can shoot off his back porch. He is wondering if a thermal will work immediately going from 70deg inside to 0deg outside.
He has a coyote bait in a shooting lane at 100yds. His usage will be . . gun with thermal on dinner table. Pick up gun,open sliding glass door and step out onto deck.
Any info/advice will be much appreciated. --- pruhdlr
 

Wildfowler

Mis'sippi
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I’ve noticed on mine when I pull it out of a warm vehicle and have it on for any length of time when it’s cold outside the image degrades quickly but other than that no real issues.

still works. It’s just not as pretty.
 

Rookie

LSB Member
I've shot many critters by throwing open the window and popping them. I've never noticed a huge difference in picture.
 

Ratdog68

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I tinkered with a low end FLIR monocular while I was working in the high arctic in Alaska. I did not have issues with the basic function during the winter, the battery went dead much quicker. The problem I had, was, polar bears are so well insulated, these low end units weren't good enough to enable me to ID them. We had high end units/cameras on the building, which worked well to enable us to clearly see the animal. I was stepping out of a 70F building into -40F (with 15mph winds). It functioned well enough to see vehicles, the pipeline, buildings... just not what we were wanting to use it for.
 

gshock

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Not sure if the commercial units go through the same testing. But most military grade sights go through a temperature shock test. The units will be put in a thermal chamber and go from real hot to real cold in a few minutes. That cycle is repeated a number of times to see how the units hold up.

Since your friend is going from 70 to 0, it should be OK. He should test it out a few times to see how the image appears from the initial shock.
 
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gshock

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I tinkered with a low end FLIR monocular while I was working in the high arctic in Alaska. I did not have issues with the basic function during the winter, the battery went dead much quicker. The problem I had, was, polar bears are so well insulated, these low end units weren't good enough to enable me to ID them. We had high end units/cameras on the building, which worked well to enable us to clearly see the animal. I was stepping out of a 70F building into -40F (with 15mph winds). It functioned well enough to see vehicles, the pipeline, buildings... just not what we were wanting to use it for.

I spent nights and weekends testing thermal units that had been sitting in the chamber at -40 for hours. We would have to open up the chamber and turn on the units to see how they functioned. A few minutes of sticking your head in the chamber at -40 will wake you up REAL quick.
 
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Ratdog68

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I spent nights and weekends testing thermal units that had been sitting in the chamber at -40 for hours. We would have to open up the chamber and turn on the units to see how they functioned. A few minutes of sticking your head in the chamber at -40 will wake you up REAL quick.
At -50F metal begins to do funny things, as it gets brittle. At -60F you can pour a freshly brewed cup of coffee, flip it into the air and HEAR it crystalize before it hits the ground as ice. The coldest ambient I've endured was -70F in Kotzebue, AK in January of 1985. That night, the wind howled in off of Siberia. We had frost coming from under the door and crawling across the carpet, towards the oil stove (glowing cherry red).

When you see temps like that for a spell, you run around in shirt sleeves when it gets "warm" (-20F) LOL
 
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