I've never had one fog up yet. Maybe you could try some Rain-X? I don't know. Someone who's had one fog might suggest something more helpful. Good Luck. For S&G's, I went to their website. Check this out. http://www.rainx.com/Products/Windshield_Treatment/Anti-Fog.aspx
The Rain-X sounds like a pretty good idea. Are you sure you are not getting moisture inside the cam? Any fogging I have ever got just dissipated as the day warmed up. You might try putting some of those sorb-it pacs inside the camera. Make sure the inside of the cam is dry though because if you are getting moisture there, it won't be long until you are going to have other problems. Blessings.....Pastorjim
Sounds like a climate issue that I've dealt with on occassion. If the pressure, tempature drops/climbs quickly in a short time this will happen. I have had some success by moving the camera to change the angles of sunlight, wind etc. that hits it at certain times in the morning therefore trying to put it in a spot where there wasn't such a quick, drastic change in tempature to keep it from forming condensation on the lens. Sometimes it works , sometimes it doesn't. I have had better success keeping the camera in the shadows-where the sun never reaches it.
Anytime there is fog in the atmosphere there is a chance you could get moisture on the olutside of the camera lense. In this case if you put the camera high on the tree and point it down toward the trail it will eliminate the moisture factor. Becareful putting any type of chemical like Rain X on the lense because if it is plastic it could make a reaction and fade the lense. I have delt with this same problem for years and there is really not a whole lot you can do other than what I said.
You have to change the angle of the camera , this will eliminate any and all issues with fogging. Also pay close attention to the suns rising and setting angles and try to avoid them if at all possible.
I put desiccant bags in all my cams,like the ones found in aspirin bottles work well for me.lifespan of cams is greatly increased for me. Anything left outside gets moisture from condensation and it will turn soldered connections green the white powder then just break off after awhile. Manufactures need to put the inside the body's of there cams from the get-go. Seems like a lot of cams don't work much past the warranty anyways.