Scope Users

[El Chivo]

Most scopes are fixed focus, at 100 or 50 yards, that's the only distance where the image is truly sharp.

It ought to be possible to attach an auxiliary lens to the front and change that distance, and sharpen up the image at either a shorter or longer distance. Sort of like an adjustable objective, but as a removable accessory.

I've been thinking about this since I tried shooting a friend's 9x scope at 200 meters and the rams were quite blurry. How annoying!

Would you purchase a set of auxiliary lenses for range shooting if they were available?

[FWiedner]

You can adjust the focus to your liking on most scopes by turning the occular bell, can't you?

... or maybe that's just on variable power scopes... ?

I've done it many times.

[TedH]

I've never found that to be a problem for me, or even noticable with a quality scope. So, no, I wouldn't buy such an item.

[Terry Murbach]

ALL THE SCOPES I'VE EVER SEEN OR USED IN 60+ YEARS OF SHOOTING HAVE INDIVIDUAL EYE FOCUSING. TURNING THE EYE PIECE IN OR OUT, JUST LIKE IN BINOCULARS, IS HOW YOU FOCUS A SCOPE. THE HIGHER POWER AND QUALITY TELESCOPIC SIGHTS [ HOW'SA THAT FOR AN OLD CORRECT NAME...] ALSO HAVE THE AE FOCUSING IN THE OBJECTIVE LENS.

[Mescalero]

[olyinaz]

ALL THE SCOPES I'VE EVER SEEN OR USED IN 60+ YEARS OF SHOOTING HAVE INDIVIDUAL EYE FOCUSING. TURNING THE EYE PIECE IN OR OUT, JUST LIKE IN BINOCULARS, IS HOW YOU FOCUS A SCOPE. THE HIGHER POWER AND QUALITY TELESCOPIC SIGHTS [ HOW'SA THAT FOR AN OLD CORRECT NAME...] ALSO HAVE THE AE FOCUSING IN THE OBJECTIVE LENS.

Not to be confused with parallax adjustment! Most scopes are fixed for parallax at 50 or 100 yards - NOT fixed for "focus".

The reticle should be clear at any range (THAT is what you focus for - point the scope at the sky and adjust focus for a sharp reticle). The target image should be reasonably clear at most ranges, but only a scope that gives you variable parallax adjustment will give you an absolutely sharp image at all ranges (within the adjustment range) AND assure that your reticle is adjusted for point of impact.

This is why many scopes now feature three knobs at the central adjustment junction, or feature an adjustable objective (the forward lens) with range markings. FOR PARALLAX. The focus adjustment is at the ocular (the back lens).

Out.

[Mescalero]

Fixed power users do not report this problem.

[olyinaz]

Fixed power users do not report this problem.

Au contraire mon frere!

http://www.opticsplanet.com/leupold-fx- ... scope.html

[Mescalero]

12x
For target work ok
for hunting.......... not enough time to reset for each different target.

[AJMD429]

The eyepiece turning I think generally is not to focus the target, but rather focuses second-focal-plane reticles or crosshairs to be sharp.

Some fixed-powers and many variables have turnable objective lenses, and those are the ones which focus on the target. They usually claim to adjust parallax as well, but I don't know if that is just an inherent property of what they are doing to focus on the target, or a truly separable function.

I might not buy an accessory lens for that unless it went on like a 'lens protector' and rubber-booted securely to the objective bell. I would settle for one that simply increased focus distance by 'double' or halved it, and didn't adjust, as the problem is mostly with lower-power scopes (fixed or variable) that don't have the adjustable objective. At those powers I wouldn't feel the need to 'fine-tune' the focus the way I might with a 20x.

I'm a scopeaholic, and use lots of relatively high power scopes, even for 'hunting', though I don't stalk/jump-shoot deer, but rather hunt from a stand. I've used 12x many times, and even a 10-40x set on 10 or so. I'd put it on 40x if I were hunting prairie dogs.

[Mescalero]

AJ, ever notice how us high power scope users always go back to them?

[AJMD429]

AJ, ever notice how us high power scope users always go back to them?

Mom always warned me I might go blind, so I changed my ways, but not soon enough I guess.

[Mescalero]

I always said ..... can I do it till I need glasses........... well, I need glasses.

[El Chivo]

I would settle for one that simply increased focus distance by 'double' or halved it, and didn't adjust,

That's what I was thinking of; the other would be too complicated. Maybe a set of two; one for closer (100 yds down to 50) one for further (100 yds up to 200).

The focusing eyepiece helps your eye see the reticle. The front of the scope is what puts an image on the reticle. That image is sharpest at 100 yds (or whatever your scope is fixed at). But it's blurry at close range or way out. Fiddling with the eyepiece won't help.

An additional lens could change that setting, just like having an adjustable objective, only removeable. And yes, it would be mostly for target work - if you want to shoot your 100 yd scope at 50 yds and temporarily want a sharp, parallax free image at 50 yds.

When I was a young photographer I had a set of 3 screw-on lenses that changed my standard lens to focus close up. That, and having a new adjustable objective scope, got me thinking.

[El Chivo]

ALL THE SCOPES I'VE EVER SEEN OR USED IN 60+ YEARS OF SHOOTING HAVE INDIVIDUAL EYE FOCUSING. TURNING THE EYE PIECE IN OR OUT, JUST LIKE IN BINOCULARS, IS HOW YOU FOCUS A SCOPE. THE HIGHER POWER AND QUALITY TELESCOPIC SIGHTS [ HOW'SA THAT FOR AN OLD CORRECT NAME...] ALSO HAVE THE AE FOCUSING IN THE OBJECTIVE LENS.

Well I haven't been shooting for 60+ years, but I was using my rimfire scope indoors, at a range much closer than it was designed for. 50 yd down to 15 yds. The target image was noticeably blurry no matter how much I turned the eyepiece. Sure, it sharpens the crosshairs, but if what's on the reticle is blurry, the eyepiece can't improve it.

After a little advice on this forum, I purchased a scope with adjustable objective, focused it on 15 yards, and bingo! sharp image and tiny groups. Although that scope is much bigger and bulkier.

Basically what I'm talking about is an attachment for scopes that don't have an AE, to have some adjustability LIKE an AE by way of an auxiliary lens. If I had had one of those to stick on my old rimfire scope, I would have been good to go for the shorter range.

[AJMD429]

When I was a young photographer I had a set of 3 screw-on lenses that changed my standard lens to focus close up. That, and having a new adjustable objective scope, got me thinking.

I remember those - I had a 35mm non-SLR camera with those, and when using them you had to measure the lens-to-subject distance. I made a wire 'frame' which affixed to a wood base the camera mounted to, and if a wildflower or other item was centered in the wire frame area, it would be in-focus. No other way to tell until the film was developed.

[Mescalero]

I reluctantly write this.
El Chivo I know 1 one guy who could possibly help with this problem................
but he will not....... he is fixated on bumping magnification of already stupidly high power scopes.
So there are people out there who can do what you want, they are doing it on the other end of the spectrum from what you want.
I do not know how to contact those in the know.
Perhaps someone with more knowledege of social media than myself could suggest another way to search.

[Washita]

If you use a scope with AO (Adjustable Objective) for target shooting and want to use it for hunting, just adjust the objective for the kind of hunting you're doing, for example, 50 yds. for squirrel, 100 yds. for deer, and leave it alone. It'll then perform exactly like a fixed-objective rimfire or center fire scope. Back in the days when I still hunted, I'd also set the scope at it's lowest magnification to get max. field of view, then crank it up if more power was desired for a standing target at long range.

Parallax and focus, as noted above, are not the same thing. Normally you only adjust focus once. to adjust focus, just aim the scope at a plain light background; a clear blue sky, for instance, then adjust till the crosshairs are sharply defined. It'll be focused at all ranges. Parallax will need adjustment, if the scope has AO, for different distances. Non-AO scopes are only exactly right at one distance usually 50 yds. for RF scopes, 100 for CF. At other distances the crosshairs will fuzz up a bit, though the degree of fuzziness is usually not much.

[AJMD429]

Non-AO scopes are only exactly right at one distance usually 50 yds. for RF scopes, 100 for CF. At other distances the crosshairs will fuzz up a bit, though the degree of fuzziness is usually not much.

I wonder if there is a 'pinhole' or aperture effect like with camera depth-of-field, where if you open up to wide f-stops you lose depth of field, but 'gather more light', whereas if you are willing to go with less light-gathering or objective diameter, you gain some depth of field...????

[olyinaz]

When I was a young photographer I had a set of 3 screw-on lenses that changed my standard lens to focus close up. That, and having a new adjustable objective scope, got me thinking.

Unfortunately, those "filter lenses" always came with a price: reduction in clarity and aberrations as you moved towards the edge of the field. I have used those plenty and while they're fun and useful, I eventually bought dedicated macro lenses because of the image shortcomings of those kind of lenses. I do have some add-on lenses that don't come with a terrible cost in performance for both my cameras and telescopes, but they cost hundreds to thousands of dollars if they're of high quality. And those good ones mount to the back of the lense (between the lens and the camera) or in the focuser on a telescope so that they can be properly/precisely placed at exactly the right spot in the light path time and time again.

It's not that what you suggest couldn't be done, but if it were to be done RIGHT it would be expensive, which sort of ruins the point (not having to just buy a new scope).

A good scope has little to no sharpness issues from about 75 yards on. Who would want a scope that is fuzzy at every range but 100 yards? Ridiculous, they'd never sell us scopes if that were how they all were. A better scope, however, allows you to adjust either a "side focus" knob or an ocular rotating bezel for really crisp and parallax free images at any range from about 25 yards to infinity. Redfield 2-7 = GOOD. Nikon Monarch 2-8 with side focus = BETTER. Ya gets what ya pays for.

These are outstanding scopes: http://tinyurl.com/ptaw6ax

[JohndeFresno]

El Chivo,

Your idea sounds very interesting.

As for my two cents as an increasingly frequent scope user - the ol' eyes, ya know:
I'd rather pay a little extra for any extra features on a reasonably good make of scope rather than have to fiddle with extra gadgets to hang on or around it.

So, if one comes up with an improvement, perhaps the way to go is to patent it and then sell it to the scope manufacturers and be done with all of the hassle of breaking into the market, stocking, paying rent for a storage area and so on.