Boo...back in the day, I heard a well known optics rep ( that you probably know, a tall blond guy from one fo the small towns just north east of Garland) expound on his line of US made scopes at a dealer one time and touched on the issue of objective bell size and pros/cons of plus 40mm in a 1" scope. Seems like past about 44mm the rate of more light being gatherd drops off to about 2-% at 50mm and less than that at 56mm. And thats wjhy his vendor did not offer as much in the way of product selection as some of the Euro brand did. Understand this was before I left the Carrollton dist that stocked & sold his product.This had to be some time in the early/mid '80's. Coatings, glass upgrades& 30mm tubes can help enormously, but physical size up front still controls how much light actually gets into the body of the scope IMO. My Minox ZA5 HD 2-10x50 30mm is waaay better at target acquisition in low light than anyhting else I found at that time in it's price range when I bought it about 18 months ago.
I've acquired a couple 50mm objective bells scopes, and can say that better glass as well as a bigger 30mm tube + the biger front end can all add up to more light to use at the end of the day.
As far as CF II's I'm still getting used to a 4x12x50 1" tube AO, but can tell enough difference from the older Buckmasters I had used for years to look at picking up another CF II in a 4x12x44 1" tube, without the A/O for a deep woods thumper.
Having been away from Nikon's for a long time, I get confused on the Prostaff designation differences from scope to scope. So far I'm satisfied with the lower end Vortex scopes... but then I'm not shooting very far either. I really like the Viper glass upgrade in the Diamondback HP over the CF II, but prolly won't buy anther 4x16x42, and drop to the 3x12x42 instead as both are SF, and mount very low to the barrel in Warne mediums.
Drug out a 10+ year old 3x9x40 Sightron S1 to mount on a Beater consignment gun this morning...still clear as a bell and controls work smoothly with solid feeling metallic clicks bore sighting it. If the Beater don't sell the S1 will go back on a 22lr.
Edited by WileyCoyote (08/01/16 09:35 PM)
"These are the times that try men's soul's"...Thomas Paine
"Those who fail to learn from History are doomed to repeat it" ....Santayana
"There's a sucker born every minute" P.T. Barnum, on why he always had customers to see the sideshow features.