Optics in Extreme Cold

[JW@TRACT]

Does anybody have experience with optics in extremely cold weather? Do they hold up? What happens when they go from a warm cabin to the frigid temps and vice versa?

 

[Formidilosus]

Does anybody have experience with optics in extremely cold weather? Do they hold up? What happens when they go from a warm cabin to the frigid temps and vice versa?

Yes. Lots.

Binos, spotting scopes, or rifle scopes?

 

[pyrotechnic]

Haven't had issues going from warm to cold. However, going the other way humidity will condense and then freeze on metal and the lenses. If the optics/rifle get cold they need to stay cold.

I haven't ran into any mechanical issues in cold (down to around -5) other than parallax and magnification rings being a bit stiffer to turn. I can't say that I've spent an enormous amount of time out shooting in those conditions or with a wide variety of optics so my experience is purely anecdotal.

 

[BluMtn]

The only issue I have had was with a Ziess HD5 scope. When it got to -20 the magnification collar would not turn anymore.

 

[JW@TRACT]

Yes. Lots.

Binos, spotting scopes, or rifle scopes?

Rifle scopes.

 

[Formidilosus]

Rifle scopes.

Sure. Of course going from hot/cold or vice versa causes condensation and fogging on the outside, worse going from cold to hot. Any breath on the lenses ices them up. Magnification rings get stiff, some will completely lock up once at some point below 0°. Erector systems can get sticky or start presenting weird issues. Parallax knobs the same.

 

[LeftyWilbury]

Fondly remember hunting at about 0F and seeing a buck move through the trees. As I lifted my rifle up i told myself, "don't breathe on the scope!" Alas, my timing was off, iced up the scope and had to frantically scrape it off. Thankfully the buck was out of his mind over a girl and ran into an opening and proceeded to angrily attack a defenseless sagebrush. I'm happy to say I saved the sagebrush from complete destruction.

Haven't had any mechanical failures at such temps. Things like knobs don't like to move as readily and low batteries are going to make you sad. I probably wouldn't take a rifle that I've been holding outside at 0F and immediately lean it next to the fire but my rifle warms up a bit in a case on the way home and I'll open up the action and lean it up in a warm room to let any condensation disappear. Air is a bit dry in MT in the winter which helps. None of my optics have ever fogged up, Sig Sauer, Weaver, Leupold, even Bushnell.

 

[mxgsfmdpx]

Quite a bit of experience with this. What is your concern?

 

[Blue72]

Sometimes you have to let your optics cool down to match the outdoor weather conditions. The bigger the optic the longer the cool down . some astronomers use a small fan to help

 

[Sandstrom]

One hot and humid summer night, my wife saw a coyote in the back yard and encouraged me to go shoot it as only a wife can. I quickly grabbed the 22 from the coat room an snuck outside. As I pulled up the gun for a shot, all I could se was condensation. Apparently the AC in our house had the temp of the gun much cooler than the dew point of out side. The coyote was safe...
Ryan