OpticsTalk by SWFA, Inc. Homepage SWFA     SampleList.com
Forum Home Forum Home > Scopes > Rifle Scopes
  New Posts New Posts RSS Feed - Fixed power scopes
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Visit the SWFA.com site to check out our current specials.

Fixed power scopes

 Post Reply Post Reply
Author
Message
gremcat View Drop Down
Optics Apprentice
Optics Apprentice


Joined: January/17/2012
Location: Raleigh NC
Status: Offline
Points: 99
Post Options Post Options   Thanks (0) Thanks(0)   Quote gremcat Quote  Post ReplyReply Direct Link To This Post Topic: Fixed power scopes
    Posted: January/19/2012 at 21:40
So I have heard and it makes sense that fixed power scopes let in more light due to less lenses. I have a 6x42 vx -3 I was thinking of throwing on my deer rifle. Shots will be 50 -200 yards will it let in more light than say a 3-9 x 40 ? I know the exit pupil effects light performance but not sure on the fixed power
Back to Top
Bitterroot Bulls View Drop Down
Optics Master Extraordinaire
Optics Master Extraordinaire
Avatar

Joined: May/07/2009
Location: Montana
Status: Offline
Points: 3416
Post Options Post Options   Thanks (0) Thanks(0)   Quote Bitterroot Bulls Quote  Post ReplyReply Direct Link To This Post Posted: January/19/2012 at 21:52
It doesn't "let in" more light really.  It is just that less light is lost through reflection, given there are less air-to-glass surface for light to bounce off of.
 
Whether you could tell the difference between a 6X42 FX-3 and a 3.5-10X40 VX-3 at 6 power, I don't know, but in theory the FX-3 would be a little brighter.
 
I would feel more than comfortable with a 6X42 FX-3 for your stated uses, but I would also be comfortable with a quality 3-9X40 variable.
 
Exit pupil is diameter of objective / magnification = exit pupil.
 
So the 6X42 is 42/6 = 7mm exit pupil.  This happens to be about the max the human eye can use.
 
The variable's exit pupil would vary from low to high magnification by the same formula.  So the exit pupils between both scopes would be about the same at 6x magnification.
-Matt
Back to Top
silver View Drop Down
Optics Master
Optics Master


Joined: November/04/2005
Location: United States
Status: Offline
Points: 2291
Post Options Post Options   Thanks (0) Thanks(0)   Quote silver Quote  Post ReplyReply Direct Link To This Post Posted: January/20/2012 at 07:20

The quality of the lenses, coatings and construction are more important than the paper numbers.  The paper numbers assume that all glass is the same.  They are not.  That's why when we get to things like exit pupils it looks good on paper, but does not factor in how much light is actually transmitted.

 
Leupolds are not known for being the best at light through put.  Rugged, yes... Bright & clear no.  Look at the F3s peers price point.  IOR is brighter and more money. 
"If we weren't all crazy we, We would go insane."   Jimmie Buffet

WWW.formitch.com

Back to Top
gremcat View Drop Down
Optics Apprentice
Optics Apprentice


Joined: January/17/2012
Location: Raleigh NC
Status: Offline
Points: 99
Post Options Post Options   Thanks (0) Thanks(0)   Quote gremcat Quote  Post ReplyReply Direct Link To This Post Posted: January/20/2012 at 10:31
How about Doctor optic any good or bad on their 6x42?
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.096 seconds.