Scope fog
08-18-2008 | 12:51 PM
#1
Thread Starter
Nontypical Buck
Joined: Apr 2005
Posts: 2,414
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From: West Virginia
Scope fog
I was reading another post and someone was saying that their scopes never fogged. That reminded me:
Every one of my scopes have fogged at one time or another. I see manufacturers talk about waterproof, shockproof and fogproof. All of my Nikon's, Bushnells and my one Leopold fogs up from my warm breath on a cold day.
WHY???
Every one of my scopes have fogged at one time or another. I see manufacturers talk about waterproof, shockproof and fogproof. All of my Nikon's, Bushnells and my one Leopold fogs up from my warm breath on a cold day.
WHY???
08-18-2008 | 01:40 PM
#2
Joined: Jan 2004
Posts: 2,174
Likes: 0
From: El Dorado, Arkansas
RE: Scope fog
The change in the ambiant temperature of the glass and the warmth of your breath causes external condensation on the lenses.... But when a manufacturer speaks of fogproof, that is referring to the internal glass... The glass inside the scope will not fog due to temperature change or condensation because the scope is nitrogen gas , or Argon gas , purged and sealed with multiple O-rings and seals at any place where the scope has a joint or connection to the outside.
So every scope can fog on the outside glass due to your breath, but that has nothing to do with claims of being fogproof.
MET
So every scope can fog on the outside glass due to your breath, but that has nothing to do with claims of being fogproof.
MET
08-18-2008 | 03:02 PM
#3
Nontypical Buck
Joined: Feb 2003
Posts: 4,970
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From: Clermont Florida U.S.
RE: Scope fog
Very well explained by Michael T. The Rainguard feature on certain Bushy scopes helps a lot in that regard. Some other scopes have similar coatings or, in the Leuppy line, screw on pretective lens' that will help. Just try to not exhale directly towards the eyepiece whwnever possible.
08-18-2008 | 03:14 PM
#4
Thread Starter
Nontypical Buck
Joined: Apr 2005
Posts: 2,414
Likes: 0
From: West Virginia
RE: Scope fog
Thanks guys. I was unaware that teh manufacturer claims were referring to the inside of the scope not fogging.
That being said what do you guys do to help prevent the fogging on the outside. I seem to recall that when i was younger and did a lot of skiing i could put something on my goggles to stop them from fogging. Is there something we can put on the scope lense that would work and be safe for the lense?
That being said what do you guys do to help prevent the fogging on the outside. I seem to recall that when i was younger and did a lot of skiing i could put something on my goggles to stop them from fogging. Is there something we can put on the scope lense that would work and be safe for the lense?
08-18-2008 | 05:06 PM
#5
Joined: Jan 2004
Posts: 2,174
Likes: 0
From: El Dorado, Arkansas
RE: Scope fog
Some companies ( not scope companies ) make anti fog sprays or creams, but the best way is to not breath directly on the lenses. If you are looking through the scope at an animal, in cold weather, breath through your nose, and train yourself to do so every time.
MET
MET
08-18-2008 | 08:17 PM
#7
Nontypical Buck
Joined: Feb 2003
Posts: 3,393
Likes: 0
From: Western Nebraska
RE: Scope fog
ORIGINAL: MichaelT.
The change in the ambiant temperature of the glass and the warmth of your breath causes external condensation on the lenses.... But when a manufacturer speaks of fogproof, that is referring to the internal glass... The glass inside the scope will not fog due to temperature change or condensation because the scope is nitrogen gas , or Argon gas , purged and sealed with multiple O-rings and seals at any place where the scope has a joint or connection to the outside.
So every scope can fog on the outside glass due to your breath, but that has nothing to do with claims of being fogproof.
MET
The change in the ambiant temperature of the glass and the warmth of your breath causes external condensation on the lenses.... But when a manufacturer speaks of fogproof, that is referring to the internal glass... The glass inside the scope will not fog due to temperature change or condensation because the scope is nitrogen gas , or Argon gas , purged and sealed with multiple O-rings and seals at any place where the scope has a joint or connection to the outside.
So every scope can fog on the outside glass due to your breath, but that has nothing to do with claims of being fogproof.
MET
08-18-2008 | 08:32 PM
#8
Boone & Crockett
Joined: Jan 2004
Posts: 12,823
Likes: 4
From: Eastern PA
RE: Scope fog
Vapordog - you da man.
If yo can find it, a good product for anti fogging your scope lens is called scope dope. It comes in a little orange plastic container. Its almost like a wax for glass. It works great on scopes, binos, spotting scopes, even eyeglasses.
If yo can find it, a good product for anti fogging your scope lens is called scope dope. It comes in a little orange plastic container. Its almost like a wax for glass. It works great on scopes, binos, spotting scopes, even eyeglasses.
08-19-2008 | 06:16 AM
#10
Nontypical Buck
Joined: Feb 2003
Posts: 3,337
Likes: 0
From: Too close to Chicago
RE: Scope fog
Thanks Swampy.
I was just going to ask about the Rain-X since I already have some for the car.
In addition to preventative products and thoughtful breathing practices, I recommend keeping a clean dry soft cloth handy to wipe fog off if it does happen. It may save you a lost shot, and you really don't want to use your finger or a dirty glove if you can help it.
I was just going to ask about the Rain-X since I already have some for the car.
In addition to preventative products and thoughtful breathing practices, I recommend keeping a clean dry soft cloth handy to wipe fog off if it does happen. It may save you a lost shot, and you really don't want to use your finger or a dirty glove if you can help it.