OpticsTalk by SWFA, Inc. Homepage SWFA     SampleList.com
Forum Home Forum Home > Scopes > Rifle Scopes
  New Posts New Posts RSS Feed - 24mm Objective optical capabilities.
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

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

24mm Objective optical capabilities.

 Post Reply Post Reply
Author
Message
Lennyo3034 View Drop Down
Optics Apprentice
Optics Apprentice


Joined: April/01/2010
Status: Offline
Points: 59
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lennyo3034 Quote  Post ReplyReply Direct Link To This Post Topic: 24mm Objective optical capabilities.
    Posted: November/05/2014 at 09:15
I'm wondering what the consensus here was for the optical capabilities of 1-6/8X24mm scopes compared to larger ones. I'm asking because I've owned a SWFA 1-6 and Bushnell 1-8.5 and neither produce as good a image as cheaper scopes with larger objectives. I haven't had the Bushnell out to the range yet, but I found it very difficult to resolve .223 holes in white at 100 yards with the SWFA. I compared them both to a Vortex PST 2.5-10X32 and the PST did noticeably better at a pine tree 300 yards away. 

Is this just the nature of the 24mm objective? Or should I keep looking for another 1-X scope? I don't expect these to compete with high end optics with high magnification and large objectives. However I figured at relatively low magnification (6X) they would at least be in the ballpark

Back to Top
NDhunter View Drop Down
Optics Journeyman
Optics Journeyman
Avatar

Joined: September/15/2006
Status: Offline
Points: 601
Post Options Post Options   Thanks (0) Thanks(0)   Quote NDhunter Quote  Post ReplyReply Direct Link To This Post Posted: November/05/2014 at 18:42

A 24mm objective scope is very small and when it is about light gathering and

exit pupil size, the FOV and other things are limited with such a small choice.

If you have any experience with binoculars anything with a small objective size down

to 20 or 25 is limited in its usefulness. 

Bigger is often better, and that is why a 40-42mm objective is the biggest seller

by far.  Not many use a 24mm scope, but a good place may be your .22 LR.

Right now, I am swapping out a 2-7x28 for a larger 3-9x40 as the small one will

not get it done hunting, often in low light.




Edited by NDhunter - November/05/2014 at 18:53
Back to Top
koshkin View Drop Down
MODERATOR
MODERATOR
Avatar
Dark Lord of Optics

Joined: June/15/2004
Location: United States
Status: Offline
Points: 13181
Post Options Post Options   Thanks (0) Thanks(0)   Quote koshkin Quote  Post ReplyReply Direct Link To This Post Posted: November/05/2014 at 19:03
Exit pupil size is indeed a function of the objective lens size and magnification.  Field of view does not have any relation ship with the objective lens size.  If anything achieving a wide field of view is easier with a small objective lens than with a large one.

If you want good low light performance at higher magnifications, you definitely need a fairly large objective lens, since you want the exit pupil to accomodate both the expanded eye pupil and the inherent movement of the eye ball.

Aside from that, keep in mind that different scopes are optimized for different things. 

In low light, look for scopes with good contrast and with large exit pupil.  For example, the 4mm exit pupil at 6 power is serviceable, but not ideal.  A 5mm exit pupil sounds like it is only marginally larger, but it brings 56% more light to the eye all other things being equal.  A 6mm exit pupil delivers additional 125%
compared to a 4mm one.

Some limitations of a small exit pupil can be compensated with excellent optics and side focus.  For example, I the 1-8x24 March scope I am playing with performs beyond what I expected for such a small scope.  I ran it side by side with very competent SWFA 1-6x24 and Meopta R2 1-6x24.  The resolution of the March is clearly better and side focus allows me to really finetune it.  It is a nearly $3k scope though.

ILya

Back to Top
Lennyo3034 View Drop Down
Optics Apprentice
Optics Apprentice


Joined: April/01/2010
Status: Offline
Points: 59
Post Options Post Options   Thanks (0) Thanks(0)   Quote Lennyo3034 Quote  Post ReplyReply Direct Link To This Post Posted: November/05/2014 at 21:59
I'm not particularly concerned about low light performance. Mainly resolution and being able to see my hits. It's annoying to have to bring a spotting scope out to the 100 yard range.

Back to Top
MZ5 View Drop Down
Optics Apprentice
Optics Apprentice


Joined: July/03/2012
Location: Arizona, USA
Status: Offline
Points: 126
Post Options Post Options   Thanks (0) Thanks(0)   Quote MZ5 Quote  Post ReplyReply Direct Link To This Post Posted: November/11/2014 at 15:19
Perhaps the Vortex made it easier because of the higher magnification?
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 0.284 seconds.