Optics trade-offs: weight, objective, eyebox

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Martin248

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I keep going back and forth between these:

Nightforce NX8 1-8x24
+lightweight -eyebox -lowlight +low-mag

Nightforce NXS 2.5-10x42
~lightweight +eyebox +lowlight -low-mag

Trijicon Credo 2-10x32
-lightweight ~eyebox ~lowlight ~low-mag

I would put it on a lightweight general purpose 308 bolt action, think a scout rifle (but trad. mounted scope) and use it for hunting and some target practice. Sling it into the woods so weight is a factor.

The form factor lends itself to wanting to be able to take quick shots (so 1x-ish, forgiving eyebox) and low light capable for hunting (but maybe shorter distance, like 4x so 24 objective might be ok). I would like it to be capable at longer ranges in daylight. SFP is fine, if I'm shooting far enough to worry about bullet drop I'll zoom all the way in.

Anyway, just when I think I've made a decision (lightweight is king, get the NX8) I focus on a different aspect (lowlight) and think no, the NXS is going to be it. Maybe the Credo is a good compromise? But it's heavier! NX8 then?

So here's my question, if you have one of these three do your really love it? And why?
 
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Everything in optics is a trade-off. For what you want the NXS is the best choice of the three. All 3 are top quality optics.
 
Everything in optics is a trade-off. For what you want the NXS is the best choice of the three. All 3 are top quality optics.

I think so too. Then I think a light weight 308 would benefit from the light weight of the NX8, and from the quick shots possible with the 1x magnification, but then I worry about low light capability and round and round I go.
 
The deciding factor would be-can you snap shoot at 2.5x? If yes, and you want the longer daylight range you say you do, the NXS is your huckleberry. If you cant snap shoot at 2.5x, The NX8 would be better, but your long range will suffer some. How much depends on how much long range shooting you've done.
 
Yes, but assuming it has a reasonable eyebox(*), it's always going to be faster with a 1x since you can focus on the target with both eyes while bringing the rifle into position, the reticle will just appear in your vision, like a red dot.

That said I have a 4x ACOG on my 556 AR, and I have learned to use Trijicon's "bindon aiming concept" which is nearly as fast, but not quite as fast as I can get an Aimpoint on target with the same rifle. So there's a speed advantage for 1x at short distances.

HOWEVER, that's not the only consideration--to get that 1x speed advantage I have to give up on low light performance, etc., like you said it's all trade-offs. And this won't be a tactical rifle, so it's not quite as imperative, but still--quick shots are nice on a light "scout" type rifle.

(*) Is the NX8 eyebox reasonable in 1x? There's a question. That whole benefit goes out the window if the answer is no.
 
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The 1-8X24 scope should still be good in low light up through about 5X. On 8X you have enough magnification for any shot at reasonable hunting range. The only negative for me is that I'd be limited to shots inside of 200-300 yards during the 1st 5-10 minutes of legal shooting time and the last 5-10 minutes of shooting time since I couldn't go above 4X or 5X. Any other time I could use the full 8X during good light.

Balance that against how fast it is to get on target up close on 1X and the 1-8X would be my choice.
 
Very well thought out and researched question. Wish I had the answer. All I can add is that low light performance is cool but never been top of my wish list. Especially not over speed
 
You pretty much guessed it from context clues. Although not square, it’s the area your eye must be in to look through the scope, bounded by both eye relief and exit pupil
 
This happens at 25x too. Just sayin’...

You're talking about what Trijicon calls their bindon aiming concept, where you let the brightly illuminated reticle appear as a blur over the target as you view it with your weak side eye, like it was an occluded red dot, and then refocus on the target through the optic with your strong side eye.

Especially at 25x the target is going to be out of focus first in one eye then the other. It takes time to refocus, not long, but time and you're denied the use of both eyes since the high magnification is quite a difference.

For me even with a 4x ACOG that is slightly slower than with a 1x. With a 1x I keep focusing on the target with both eyes and never have to refocus. It's faster. It's also easier to scan through the scope and track a target with both eyes--better depth perception.
 
You're talking about what Trijicon calls their bindon aiming concept,

The technique existed long before Trijicon was a twinkle in the eye. It’s a simple principle of superimposition.

where you let the brightly illuminated reticle appear as a blur over the target as you view it with your weak side eye,

The technique has nothing to do with illumination.

God built within our bodies the innate ability to superimpose the images from both of our eyes into one mosaic image. Regardless of magnification, if we focus on our target downrange with our off-scope eye, if our aiming eye is aligned in the scope, we will see the reticle, and our brain will work to stitch the images together, re-establishing continuity of the visual field, so we’ll see and feel which way our reticle needs to move to come onto target. Once the target is acquired, focus shifts to the reticle and we make the shot on target.

Nothing magic about it - our eyes and brains are hard wired to do it naturally. Some folks are apparently worse at things than others, and that’s natural too.
 
You're talking about what Trijicon calls their bindon aiming concept, where you let the brightly illuminated reticle appear as a blur over the target as you view it with your weak side eye, like it was an occluded red dot, and then refocus on the target through the optic with your strong side eye.

Especially at 25x the target is going to be out of focus first in one eye then the other. It takes time to refocus, not long, but time and you're denied the use of both eyes since the high magnification is quite a difference.

For me even with a 4x ACOG that is slightly slower than with a 1x. With a 1x I keep focusing on the target with both eyes and never have to refocus. It's faster. It's also easier to scan through the scope and track a target with both eyes--better depth perception.

I’ve been dragging myself ever so slowly into the 20th Century (yes I’m still that far behind) in terms of scopes from 4x to 3-9x into the 14.5-16x and higher range. The transition training takes time but @Varminterror is absolutely correct; the brain will stitch the image. I suspect many like me who never fiddled with quality, higher magnification scopes will be slower without continued practice. This also assumes the rifle and scope fit is properly on.
 
Yes, but assuming it has a reasonable eyebox(*), it's always going to be faster with a 1x since you can focus on the target with both eyes while bringing the rifle into position, the reticle will just appear in your vision, like a red dot.

That said I have a 4x ACOG on my 556 AR, and I have learned to use Trijicon's "bindon aiming concept" which is nearly as fast, but not quite as fast as I can get an Aimpoint on target with the same rifle. So there's a speed advantage for 1x at short distances.

HOWEVER, that's not the only consideration--to get that 1x speed advantage I have to give up on low light performance, etc., like you said it's all trade-offs. And this won't be a tactical rifle, so it's not quite as imperative, but still--quick shots are nice on a light "scout" type rifle.

(*) Is the NX8 eyebox reasonable in 1x? There's a question. That whole benefit goes out the window if the answer is no.
What are you hunting that requires this fast / quick shots?
My lowest power is a fixed 4x that works just fine on black bear or white tail
 
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