Power has alot to do with light gathering too. the more power the less light gathering.That is why I bought the Burris Euro-Diamond 2.5x10x44. Of course this is a 30mm main tube instead of a 1" main tube which also gives more light. But this is mounted on a Remington 700xcr in 270wsm where I will be shooting farther then a shotgun or muzzleloader. so i could crank it down to 2.5 power.Where mostwould put a 4x16 on the 270wsm. I have shot elk with a 1.5x5 with 20mm objective on a 338win. at dawn and dusk.I just crank the power down to 2x.