MichaelT.

But with all of that said, in low light situations, a 50mm will allow you to see a hair better than a 40 mm when comparing two like scopes. Yes, EURO glass is better than Japaneese glass for all intents and purposes .... across the board..... but if you are comparing a Nikon and a Simmons, that is not a fair comparison. If you are comparing a Zeiss and a Tasco ..... thats not fair .... but comparing to alike scopes of same manufaturer, model , andstyle, but one with a 40 and one with a 50 .... the 50 will see better. NOT A LOT BETTER .... BUT JUST A HAIR BETTER......

bigcountry

Resolves about 25% better.

bucksnortinted

HI tow2,man there sure is alot of answers it's all about the quality of glass,which is true.BUT you take a scope apples to apples as in tasco 40vs50mm or simmons 40vs.50mm or nikon,lupy,zeiss etc.the 50mm will give you 15minutes of extra lite in any of those scopes thats the difference you have in the extra money you will spend,the quality of glass means alot, the difference of being able to see 15more min. is important to me because if your whitetail hunting or big game the big boys movemore at dawn and dusk,do the SIMPLE TEST that I did sit out there till dark with the same scope one 40mm and one 50mm we did the test,hands down you will spend the extra money on the 50mm.try it and let me know which one you picked.........Ted

barry1me

I just got my first 50mm Mueller 4x16x50 and its great...I went and looked through a Nikon 3x9x40 last night and couldnt believe how much more light came through the Mueller.

Sheridan

IMO a 44MM is ideal for good light gathering ability & low mount for good cheek weld.