Expensive scopes fog too!
11-21-2008, 09:48 AM
#21
Senior Member
Join Date: Jan 2004
Location:
Posts: 1,813
RE: Expensive scopes fog too!
ORIGINAL: no_skill
I beg to differ on that one... I used to go out for PT without my glasses because they would fog up when I'd get outside. Fort Leonardwood is cold as hell ecspecially in the morning, but when I started running it would get worse. Then finally about 30mins into a PT session they would un-fog. So I think it depends entirely on the type of lens...
ORIGINAL: TreednNC
No. It works the same way defroster in your car does....
The warm glass evaporates what moisture is on the glass, and doesn't attract moisture (fog) to the glass. Bringing a scope from warm to cold wont bother it, cold to warm, and you'll fog up.
ORIGINAL: mauser06
common practice in many PA deer camps is to leave rifles outside in the woodshed or similar...safe and secure of course...
just for the temp change reason..80 degree camp to 20 degrees outside your going to have issues....
even when im home i leave my rifle safely in the unheated garage when its rifle season.
common practice in many PA deer camps is to leave rifles outside in the woodshed or similar...safe and secure of course...
just for the temp change reason..80 degree camp to 20 degrees outside your going to have issues....
even when im home i leave my rifle safely in the unheated garage when its rifle season.
The warm glass evaporates what moisture is on the glass, and doesn't attract moisture (fog) to the glass. Bringing a scope from warm to cold wont bother it, cold to warm, and you'll fog up.
DM
11-22-2008, 10:34 AM
#22
Giant Nontypical
Join Date: Feb 2003
Location: Texas - BUT NOW in Madison County, NY
Posts: 6,270
RE: Expensive scopes fog too!
"I beg to differ on that one... I used to go out for PT without my glasses because they would fog up when I'd get outside. Fort Leonardwood is cold as hell ecspecially in the morning, but when I started running it would get worse. Then finally about 30mins into a PT session they would un-fog. So I think it depends entirely on the type of lens... "
Hmmm..... Warm air is thinner than cold air. Warm air therefore permits more molecules of moisture to occupy the space between air molecules than does cold air. When a cold object touches warm, moist air, it causes the air to contract and squeeze out some of the moisture, causing fogging (or rain, if we're at the MACRO level).
Just keep a scope out in the cold for a day, then take it into a warm, moist room and observe what happens to the cold glass. Likewise, if you are hunting and get pretty heated up by climbing the mountain, warm., moist air rising from inside your clothing will cause fog on the coldlenses of your glasses and the ocular lens of the scope when you try to look thru it...... at least for me, this happens. It is at such times that I reallyenvy those who do not need glasses.
Hmmm..... Warm air is thinner than cold air. Warm air therefore permits more molecules of moisture to occupy the space between air molecules than does cold air. When a cold object touches warm, moist air, it causes the air to contract and squeeze out some of the moisture, causing fogging (or rain, if we're at the MACRO level).
Just keep a scope out in the cold for a day, then take it into a warm, moist room and observe what happens to the cold glass. Likewise, if you are hunting and get pretty heated up by climbing the mountain, warm., moist air rising from inside your clothing will cause fog on the coldlenses of your glasses and the ocular lens of the scope when you try to look thru it...... at least for me, this happens. It is at such times that I reallyenvy those who do not need glasses.
11-22-2008, 12:52 PM
#23
Nontypical Buck
Join Date: Nov 2006
Location: central Ky
Posts: 2,867
RE: Expensive scopes fog too!
It can happen due to warm face/breath air hitting the glasses and fogging them up. I sweat a LOT so it's hard for me to wear glasses anytime,but especially safety glasses because when I'm wearing safety glasses,I'm usually working on something.
