Hi Rob
On my Vixen 30x125 giant binos I use a Kendrick 8” SCT sized dew strap wrapped around the built in lens hoods covering the objectives and a
Dew-Not bino dew strap for the eyepieces, purchased from
Scopestuff.
Using these, the binos have never dewed up. I don’t slew the Vixen around; it’s too big and heavy, so I tend to stay in one region and cruise, so the cables hanging off the beast are not a problem.
You feel a very slight, but nice warmth on your eyes and I haven’t noticed any seeing degradation. Even if there were some seeing loss, it would still be a big improvement on fogged up, useless glass.
Cheers
Dennis