Visit the SWFA.com site to check out our current specials. |
24mm Objective optical capabilities. |
Post Reply |
Author | |
Lennyo3034
Optics Apprentice Joined: April/01/2010 Status: Offline Points: 59 |
Post Options
Thanks(0)
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 |
|
NDhunter
Optics Journeyman Joined: September/15/2006 Status: Offline Points: 601 |
Post Options
Thanks(0)
|
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 |
|
koshkin
MODERATOR Dark Lord of Optics Joined: June/15/2004 Location: United States Status: Offline Points: 13181 |
Post Options
Thanks(0)
|
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 |
|
Lennyo3034
Optics Apprentice Joined: April/01/2010 Status: Offline Points: 59 |
Post Options
Thanks(0)
|
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.
|
|
MZ5
Optics Apprentice Joined: July/03/2012 Location: Arizona, USA Status: Offline Points: 126 |
Post Options
Thanks(0)
|
Perhaps the Vortex made it easier because of the higher magnification?
|
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |