How to stop the scope from fogging up?



  • Last night I had to stop the hunt because the scope lenses were fogged (not on the inside lenses) very bad and could not see the objective clearly. Do you know a remedy that works for this?



  • Don't bring the rifle from cold to hot areas, and don't breath on the lenses.



  • I have the same problems with my thermal and night vision when I’m hunting hogs at night and the humidity is real bad usally around the same time the dew falls seems to be when it happens the most often. Still haven’t figured out a good way to avoid it, so let me know if you figure something out.



  • @bull81 exactly what you just described. I read that there is a product that seems to work, it's called fogtech, if I can get it I'll tell you how it works.



  • @toni
    Thanks fella



  • I've used the product 'Cat Crap' on goggles before, and it works.
    It appears they make a similar product for scopes, called "scope dope."
    Personally, I wouldn't want to use it on high end optics, nor have I ever tried it in that application.
    But here is the link for your reference none the less (which shows both products):

    https://ekusa.com/product-category/cat-crap/



  • Look into the stuff paintballers use on their facemasks.

    Though applying stuff to high end optic lenses would make me nervous.



  • @orkan
    That’s a good point, my thermal has a protective lens protecting the germanium lens buts it’s not user serviceable and no telling what it cost to have replaced.



  • @orkan said:

    Look into the stuff paintballers use on their facemasks.

    Though applying stuff to high end optic lenses would make me nervous.

    Hey Orkan

    Can you check with TT if there is anything we can use on their scopes. Reason I ask is that in most cases keeping the weapon secure means keeping it inside. We're probably talking about a 40-50 degree F swing. Don't mind putting my $600 setup on the screened in porch, but the new setup... I might have it tethered with a string attached to my toe while I sleep...Well... Almost...



  • I leave my DTA sitting out for an hour or so when it is hot outside before I shoot. However I leave it sitting where I can see it from my office window. In the winter i have not seen an issue With temp difference...but it hasnt been real cold either.



  • Scuba divers use baby shampoo or dish soap diluted in water. They dip their masks in it and let it dry, leaving a light soap film behind. I don't see how either of these detergents could be damaging to scope glass.

    Everything happens for a reason. Sometimes the reason is you're stupid and make bad decisions.

    0


  • I called Vortex Optics and their Tech Support Rep Nick said that he uses a Q-Tip and puts one Drop of Dawn Dishwashing liquid on it then rubs it on the lenses leaving a thin layer and lets it dry. Then he said to wipe the lenses with a micro fiber cloth and you are good to go. A thin layer of the soap is left that shouldn't be visible and you are good to go.

    BTW here in Ft Lauderdale, we spit in our masks and wiped it around with our fingers before we went under. It sounds nasty but it worked. Don't plan on doing that with my scopes though.



  • @martino1 said:

    Hey Orkan

    Can you check with TT if there is anything we can use on their scopes. Reason I ask is that in most cases keeping the weapon secure means keeping it inside. We're probably talking about a 40-50 degree F swing. Don't mind putting my $600 setup on the screened in porch, but the new setup... I might have it tethered with a string attached to my toe while I sleep...Well... Almost...

    What is the situation, exactly, where you're fogging up your TT?

    Keep the rifle inside for the night. Get up, go outside in cold, hunt. No problem.
    Everyone knows you just DON'T bring your rifle in from the cold and then expect to go right back out in a couple minutes. You have to wait for the optic to come up to temp and the haze will evap.

    So what's the issue? If you're not breathing on your lenses no big deal. If you are breathing on your lenses, then not much of anything is going to stop them from fogging. Most anti-fog sprays put a film on the lenses, and I don't care if it doesn't hurt the coatings or not, I'm not going to put a film of anything on top of a $4500 lens system.



  • I am not sure how you would do what I'll share here on scopes, but I'll share what I used to do with my camera lenses when shooting weddings in Chicago winters. In Chicago during winter shooting weddings, it was common to be doing some bride & groom shots outside after the ceremony and then walk into the warm reception and there goes your lens fogging up. To avoid this, before entering the reception I would put my camera with lens in a large zip lock bag and close it. This way when I would walk in the reception, the condensation would form on the bag and not the lens. All I had to do was give it about 1-2 mins before pulling the camera out of the bag and I was golden.

    Because the scope is attached to the gun and you can't completely enclose it in a bag, this wouldn't work. The idea is to get the condensation to from in a secondary barrier rather than on the scope. I would also be leery about putting any chemicals on the glass of the scope, same reason we use dust pens for camera lenses.



  • I think what started this thread is really more about condensation than fog. The op talked about it being a problem at night. I know when I hunt hogs at night and the humidity and temperature is just right a thick fog or what I call condensation builds up on both lens. Sometimes it’s so thick that it runs down the lens and drips off. When this happens the rifles and optics have usally been in use for hours so I don’t think it’s in anyway related to temperature changes from being indoors or a vehicle to the outdoor temperature. I’ve noticed that this happens usally around the time the dew falls at night. Not sure there is anything that can help avoid that, but if anyone figured something out I’d love to give it a try.



  • I wonder if that's a southern thing? ... I've been out for long hours day and night and haven't had my scope condensate like that before. Do you suppose it has to be near 100% humidity for it to occur?



  • @orkan

    Oh I’d be will to bet money on it cause our humidity is ridiculous. I think it’s a combination of things that line up kinda like a perfect storm so to speak. High humidity on hot nights then if the temperature falls fairly fast is when it seams to be the most problem. Been trying to talk my wife into moving to Colorado or Wyoming for several years, hasn’t gotten me very far though.



  • Wyoming is a nice state!



  • @orkan

    As you know this is my first year with the TT. My buddy has a screened in porch that would be easy to get into so I didn't leave the Keepers out on the porch over night in the past. I guess I could put them out there while I'm cooking breakfast at 3-4:00am. I head out to the stands sometime after 6:00 depending on how far the stand is that I'm going to hunt at that day. Don't move that fast or far these days. 2 hours ought to do it.



  • @bull81 said:

    I think what started this thread is really more about condensation than fog. The op talked about it being a problem at night. I know when I hunt hogs at night and the humidity and temperature is just right a thick fog or what I call condensation builds up on both lens. Sometimes it’s so thick that it runs down the lens and drips off. When this happens the rifles and optics have usally been in use for hours so I don’t think it’s in anyway related to temperature changes from being indoors or a vehicle to the outdoor temperature. I’ve noticed that this happens usally around the time the dew falls at night. Not sure there is anything that can help avoid that, but if anyone figured something out I’d love to give it a try.

    That's exactly what happens here on fall and winter nights when hog hunting. Everything gets wet and it's hard to see through the scope.



  • Thing is...as long as there is condensation on the lenses of the scope, there is also condensation in the barrel. That condensation in the barrel will cause your first 3-4 shots to be unpredictably off target by up to about 1.5 MOA. (ask me how i know this)

    Now for where I hunt that is not an issue as my shots are under 200 yards...but for someone taking a 500 yard shot on a deer 1.5 moa is enough to completely miss the deer...or gut shot it for a 2 mile blood trail.



  • @dddoo7 said:

    Thing is...as long as there is condensation on the lenses of the scope, there is also condensation in the barrel. That condensation in the barrel will cause your first 3-4 shots to be unpredictably off target by up to about 1.5 MOA. (ask me how i know this)

    Now for where I hunt that is not an issue as my shots are under 200 yards...but for someone taking a 500 yard shot on a deer 1.5 moa is enough to completely miss the deer...or gut shot it for a 2 mile blood trail.

    Didn't even think about that. Most of my shots have been inside 100 yds, last year was 125. It's been pretty warm last few years during deer season. Skinned all of my deer for the last 4 years in a long sleeve t-shirt. We don't have much water around so fog generally wasn't an issue at the property I hunt. Worst case, I leave the Howa out on the porch and call it a day.



  • @martino1

    taking a hot rifle out into the cold has not proven to be an issue for me. however...taking a cold rifle out into the hot is an issue. Usually when hunting we are going from warm to cold which should not cause condensation. condensation sets on colder items.

    however in Tennessee there will likely be some 75 deg days during deer season....or it might be 18 just depends.



  • @martino1 said:

    @orkan

    As you know this is my first year with the TT. My buddy has a screened in porch that would be easy to get into so I didn't leave the Keepers out on the porch over night in the past. I guess I could put them out there while I'm cooking breakfast at 3-4:00am. I head out to the stands sometime after 6:00 depending on how far the stand is that I'm going to hunt at that day. Don't move that fast or far these days. 2 hours ought to do it.

    Unless it's colder where you're sleeping than it is outside, I fail to see how taking a warm rifle out in the cold is going to create an issue.



  • I live in Georgia, in a swamp where the humidity is astronomical. I've found that leaving my gun in the safe with the dehumidifier bar works really well in the summer because the rifle is pretty warm already. On the other hand, taking the rifle from inside the house (73 degrees), not in the safe, where there's a 25 degree swing will condense the entire rifle to the point water drips off the barrel.

    I had a Vortex that would internally fog and i sent it back and they sent me a new one. I don't think it should fog internally, but I'm no optic expert.



  • @stormin_moorman said:

    I don't think it should fog internally

    It shouldn't.


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