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Rifle Scopes Adjusted -0 paralax versus focus
- Thread starter 1lnbrdg
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Re: Adjusted -0 paralax versus focus
First, adjust the ocular focus to get the reticle in proper focus. Either point the scope at the sky (NOT directly at the sun, obviously!) or at a brightly-light surface (a living-room wall works just fine). Take quick glances through the scope at the reticle, allowing your eye to focus at something in the distance between looks, and adjust the ocular such that the reticle immediately comes into natural focus.
Second, adjust the parallax such that the target is in focus. This should eliminate parallax, as the reticle should be focused on the same plane as the target image.
First, adjust the ocular focus to get the reticle in proper focus. Either point the scope at the sky (NOT directly at the sun, obviously!) or at a brightly-light surface (a living-room wall works just fine). Take quick glances through the scope at the reticle, allowing your eye to focus at something in the distance between looks, and adjust the ocular such that the reticle immediately comes into natural focus.
Second, adjust the parallax such that the target is in focus. This should eliminate parallax, as the reticle should be focused on the same plane as the target image.
Re: Adjusted -0 paralax versus focus
I've set the ocular focus. When I get the target focus, I can see the cross-hairs moving on the target, thus I have paralax issues. When I get the paralax where the crosshairs aren't moving, the target is out of focus.
I've set the ocular focus. When I get the target focus, I can see the cross-hairs moving on the target, thus I have paralax issues. When I get the paralax where the crosshairs aren't moving, the target is out of focus.
Re: Adjusted -0 paralax versus focus
What scope are you using? Some scopes just suck ass and never correct it !
What scope are you using? Some scopes just suck ass and never correct it !
Re: Adjusted -0 paralax versus focus
I have 4 scopes. from 3 different manufacturers that all do the same thing. 1 older Redding competition, 1 Weaver and 2 Leupolds.
I was wondering if it was my eyes, or is there a way to adjust for this?
Leupold says there's nothing wrong with their scopes and I can't say that there is since the other scopes do the same thing.
I have 4 scopes. from 3 different manufacturers that all do the same thing. 1 older Redding competition, 1 Weaver and 2 Leupolds.
I was wondering if it was my eyes, or is there a way to adjust for this?
Leupold says there's nothing wrong with their scopes and I can't say that there is since the other scopes do the same thing.
Re: Adjusted -0 paralax versus focus
In your reply to Eric Bryant you stated that you've "already set the ocular focus." However, the fact that you are having the same parallax issue with four (4) different scopes (unlikely across 4 scopes and two of them being from the same manufacturer) it sounds like the Parallax has not been correctly adjusted. Adjusting the Ocular Lens (aka the "Diopter", or "Eyepiece") on a scope is the first thing that should be done after the scope has been mounted and leveled. Even if you've already adjusted the diopter, if you haven't followed the procedure exactly as I've laid it out below you should, as it is THE CORRECT WAY, plain and simple. Even the Nightforce Owner's Manual suggests a somewhat questionable step in the procedure, namely instructing people to "look through the riflescope eyepiece at a light colored background such as a white wall...".
Following that suggestion isn't the best way to focus the Ocular / Diopter / Eyepiece because the best way to adjust the reticle is to adjust it without distraction to the eye, and the best way to eliminate any distraction is to have nothing else in the view except the reticle. This is why the Ocular should be adjusted while viewing the reticle against a cloudless sky (or at least a clear area of the sky). A blank wall is "OK", but clear sky is best because the reticle will be the only visible object within view.
Below is the correct procedure for Diopter (Ocular/Eyepiece) adjustment for both fixed and variable power scopes. The procedure is the same regardless of scope manufacturer, or whether the objective/parallax focus is on the objective ring or is a side focus type.
NOTE: If the scope is a fixed power unit skip steps 1 and 2 as they do not apply.
(1) Turn the magnification ring to maximum (highest power).
(2) Turn the Parallax focus to "Infinity" (the symbol for Infinity looks like a figure eight). NOTE: Most non-side focus scopes use a ring on the objective bell to adjust parallax, and the distances are usually numbered. Side focus parallax adjustment knobs may or may not have distances marked.
(3) Turn the ocular bell/eyepiece all the way in.
(4) Aim the scope at a cloudless section of the sky (you don't want anything except sky in the view, or else your eye will naturally attempt to focus on the object in the view beyond the reticle.
(5) Look at something nearby, but not too close, then look through the scope at the reticle. If the reticle is out-of-focus turn it a bit to begin to focusing the reticle, but look away from the scope. Never look at the reticle for more than a couple of seconds when adjusting the eyepiece (if you look at the reticle for more than a second or two your eye will naturally begin to adjust to bring the reticle into focus - and you don't want this to happen. You want to be able to look through the scope and see a sharply focused reticle immediately with your eye relaxed. This cannot be achieved by continuously looking through the scope and turning the eyepiece into focus in one continous motion because your eye will have already begun to adjust.
Note that the threads on Diopter adjustments are normally very fine, so you may have to turn the Diopter more than you might expect before any appreciable difference in reticle focus is discernable. You will most likely have to make several small adjustments before you get the reticle perfectly and finely-focused for your eye, but it is very important that you do so. A lot of shooters' "chase the focus" because they didn't set their diopter adjustment correctly when they initially set-up the scope.
Remember, look away every few seconds and make small adjustments to dial-in the Ocular/Eyepiece focus. Once you have achieved this, you should not adjust the eyepiece at all, except to maintain sharp reticle focus as your vision changes over time (it always does). You may want to put a pen mark on the eyepiece indexed to the index dot on the scope tube - if the tube doesn't have an index mark use a pencil. That way, if someone else shoots your rifle and adjusts the Ocular you know where to return the adjustment to.
If you cannot achieve simultaneous reticle and image focus after following the above directions for Eyepiece/Ocular Focus, it is possible that there is a problem with the scope.
NOTE: Setting the diopter at the extreme end of it's adjustment range in either direction can affect the image focus. Also, since all of the lenses in a scope except for the reticle are curved, when using aggressively canted bases (as suggested by S & B for their PMII line) the eye may be pushed out of center of the lens slightly blurring the reticle. The quality of the lens and coatings, and the user's vision, i.e. astigmatism, can also affect the reticle focus.
Keith
In your reply to Eric Bryant you stated that you've "already set the ocular focus." However, the fact that you are having the same parallax issue with four (4) different scopes (unlikely across 4 scopes and two of them being from the same manufacturer) it sounds like the Parallax has not been correctly adjusted. Adjusting the Ocular Lens (aka the "Diopter", or "Eyepiece") on a scope is the first thing that should be done after the scope has been mounted and leveled. Even if you've already adjusted the diopter, if you haven't followed the procedure exactly as I've laid it out below you should, as it is THE CORRECT WAY, plain and simple. Even the Nightforce Owner's Manual suggests a somewhat questionable step in the procedure, namely instructing people to "look through the riflescope eyepiece at a light colored background such as a white wall...".
Following that suggestion isn't the best way to focus the Ocular / Diopter / Eyepiece because the best way to adjust the reticle is to adjust it without distraction to the eye, and the best way to eliminate any distraction is to have nothing else in the view except the reticle. This is why the Ocular should be adjusted while viewing the reticle against a cloudless sky (or at least a clear area of the sky). A blank wall is "OK", but clear sky is best because the reticle will be the only visible object within view.
Below is the correct procedure for Diopter (Ocular/Eyepiece) adjustment for both fixed and variable power scopes. The procedure is the same regardless of scope manufacturer, or whether the objective/parallax focus is on the objective ring or is a side focus type.
NOTE: If the scope is a fixed power unit skip steps 1 and 2 as they do not apply.
(1) Turn the magnification ring to maximum (highest power).
(2) Turn the Parallax focus to "Infinity" (the symbol for Infinity looks like a figure eight). NOTE: Most non-side focus scopes use a ring on the objective bell to adjust parallax, and the distances are usually numbered. Side focus parallax adjustment knobs may or may not have distances marked.
(3) Turn the ocular bell/eyepiece all the way in.
(4) Aim the scope at a cloudless section of the sky (you don't want anything except sky in the view, or else your eye will naturally attempt to focus on the object in the view beyond the reticle.
(5) Look at something nearby, but not too close, then look through the scope at the reticle. If the reticle is out-of-focus turn it a bit to begin to focusing the reticle, but look away from the scope. Never look at the reticle for more than a couple of seconds when adjusting the eyepiece (if you look at the reticle for more than a second or two your eye will naturally begin to adjust to bring the reticle into focus - and you don't want this to happen. You want to be able to look through the scope and see a sharply focused reticle immediately with your eye relaxed. This cannot be achieved by continuously looking through the scope and turning the eyepiece into focus in one continous motion because your eye will have already begun to adjust.
Note that the threads on Diopter adjustments are normally very fine, so you may have to turn the Diopter more than you might expect before any appreciable difference in reticle focus is discernable. You will most likely have to make several small adjustments before you get the reticle perfectly and finely-focused for your eye, but it is very important that you do so. A lot of shooters' "chase the focus" because they didn't set their diopter adjustment correctly when they initially set-up the scope.
Remember, look away every few seconds and make small adjustments to dial-in the Ocular/Eyepiece focus. Once you have achieved this, you should not adjust the eyepiece at all, except to maintain sharp reticle focus as your vision changes over time (it always does). You may want to put a pen mark on the eyepiece indexed to the index dot on the scope tube - if the tube doesn't have an index mark use a pencil. That way, if someone else shoots your rifle and adjusts the Ocular you know where to return the adjustment to.
If you cannot achieve simultaneous reticle and image focus after following the above directions for Eyepiece/Ocular Focus, it is possible that there is a problem with the scope.
NOTE: Setting the diopter at the extreme end of it's adjustment range in either direction can affect the image focus. Also, since all of the lenses in a scope except for the reticle are curved, when using aggressively canted bases (as suggested by S & B for their PMII line) the eye may be pushed out of center of the lens slightly blurring the reticle. The quality of the lens and coatings, and the user's vision, i.e. astigmatism, can also affect the reticle focus.
Keith
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Keith,
I just went through this process several times and I find an interesting result. The mark (or dot) on my Schmidt and Bender 5-25x56 PMII bell ends up right in between the "+" and the "-" and right on the "0" mark on the scope body. So to be clear, my scope requires no ocular adjustment plus or minus. Can I ask you a question then? If I have my vision corrected to 20/20 (or even 20/15 in my case) that would mean that I do not need to adjust the ocular plus or minor either way, correct?
Great post by the way. Taking my time and really not focusing on the reticle while I adjusted the ocular bell was the key. It really helped me get my ocular set correctly since I was have similar troubles with my parallax adjustment not focusing the reticle and the target at the same time. I would focus on the target and then the reticle would be out of focus, and vice versa. I was trying to get objective testing completed via this thread: http://www.snipershide.com/shooting/snipers-hide-rifle-scopes/215325-finnaccuracy-optics-test.html .
Thank you Keith and I really appreciate your help with the forum.
That would generally be correct, assuming that the scope is properly manufactured.
I wear two different sets of glasses - one that corrects my nearsighted vision to around 20/15 for outdoor use, and another that slightly undercorrects it (by about -0.75 diopter) for computer and bench work. If I use the scope's diopter correction with my "indoor" lenses, I'll have to go slightly towards the "-" end of the adjustment range (exactly as expected).
Tag for Later also.
I would like to add that when shooting this year I notice that the crosshair would move when I moved my head in the scope. My friend told me to set my parallax. So I did a adjustment and got it to were when I moved my head the crosshair didn't move. I have been shooting all my life and it didn't click until this summer. Just make sure you are in focus first. Just my little experience maybe this will help someone else.
I would like to add that when shooting this year I notice that the crosshair would move when I moved my head in the scope. My friend told me to set my parallax. So I did a adjustment and got it to were when I moved my head the crosshair didn't move. I have been shooting all my life and it didn't click until this summer. Just make sure you are in focus first. Just my little experience maybe this will help someone else.
One thing I have learned is to never stop. And the best way to stop learning is to assume you know it all. I admit, I know every little and thus I improve every time I go shooting, every time I ask questions, every time I admit I do not know. I would have never had thought I had an issue with my ocular adjustment until I REALLY put my scope through its paces. It was only when I started wondering why my scope was not doing well in the optics test that I began to realize I was the problem, not the scope.
Keep sharing everyone.
Guys,
It's much less typical for the reticle focus and parallax to coincide perfectly than the other way around. One of those stupid things in life where we can't have our cake and eat it too.
A consistent cheek weld (adjustable cheek piece's rock!) and a double check to make sure your eye is centered in the eyebox helps evade Parallax error.
The closer the parallax is adjusted to infinity and correspondingly the farther the distance for the image to be focused, the less the parallax error is prevalent.
It's much less typical for the reticle focus and parallax to coincide perfectly than the other way around. One of those stupid things in life where we can't have our cake and eat it too.
A consistent cheek weld (adjustable cheek piece's rock!) and a double check to make sure your eye is centered in the eyebox helps evade Parallax error.
The closer the parallax is adjusted to infinity and correspondingly the farther the distance for the image to be focused, the less the parallax error is prevalent.
Is it possible to my eyeglasses to introduce a parallax error independent of the scope? I ask because nothing I do gets rid of a slight parallax error in my scope, when I have my glasses on.. but if I take my glasses off, and refocus everything, the parallax error is gone.. Its a royal PITA to take my glasses on and off, so I leave them on when I shoot, but again, that parallax error with the glasses is throwing off my game at longer ranges.. Ever heard of this, or know how to fix it???
I use sunglasses with cheater reading lens sections at the bottom. That way I can see the knobs but not have correction on the scope..
Bifocal Sport Sunglasses
Bifocal Sport Sunglasses
Yes, glasses do introduce parallax issues. Unfortunately, glasses are designed to be corrective straight in front of you eyes. In a shooting position, you tend to look through the top of the lenses and not in the center which could cause issues. This is why I where contacts when shooting but the most important thing is to have a consistent cheek weld. There is no parallax issues if you look straight down the center of the scope consistently.
I also go with contact lenses. They follow my eye much better than any glasses could.
Things to remember about parallax;
Parallax (on a rifle scope) is a correction, not a focusing feature.
-Most all long range scopes (older or new fixed and lower adj.mag.) were set to be parallax free at 100 yards.
-Newer high magnification scopes require more optical adjustment, especially from 100 yards or meters and closer.
-Parallax is more critical for absolute precision below 100 yards. That's why when working at 100 and below you will find allot more adjustment than working beyond 100.
-Most quality scopes only use an infinity mark and a close adjustment mark with sometimes a mark in the "range" off 100 yards". Scope manufactures that mark distances on the parallax adjustment are seldom precise...always use your better judgment and experience.
-After the parallax is corrected the ocular often needs re-focusing to various degrees depending on the shooters eyesight. That's why you see more and more "quick focus" eyepieces on better scopes nowadays.
-At Ft. Benning the method taught (for precision shooting at longer distances) is, with the ocular already basically set for the shooter;
Set the parallax into adjustment...then re-focus your eye piece.
When you change magnification on a target...always correct for parallax and then check/readjust your eye piece.
If you hunt or shoot at repetitive distances you can put markings on the parallax knob for each distance at a certain magnification.
Parallax (on a rifle scope) is a correction, not a focusing feature.
-Most all long range scopes (older or new fixed and lower adj.mag.) were set to be parallax free at 100 yards.
-Newer high magnification scopes require more optical adjustment, especially from 100 yards or meters and closer.
-Parallax is more critical for absolute precision below 100 yards. That's why when working at 100 and below you will find allot more adjustment than working beyond 100.
-Most quality scopes only use an infinity mark and a close adjustment mark with sometimes a mark in the "range" off 100 yards". Scope manufactures that mark distances on the parallax adjustment are seldom precise...always use your better judgment and experience.
-After the parallax is corrected the ocular often needs re-focusing to various degrees depending on the shooters eyesight. That's why you see more and more "quick focus" eyepieces on better scopes nowadays.
-At Ft. Benning the method taught (for precision shooting at longer distances) is, with the ocular already basically set for the shooter;
Set the parallax into adjustment...then re-focus your eye piece.
When you change magnification on a target...always correct for parallax and then check/readjust your eye piece.
If you hunt or shoot at repetitive distances you can put markings on the parallax knob for each distance at a certain magnification.
You're welcome
Keith
Aries64 said:
Theoretically, YES. In a perfect world the Diopter is set to "zero" (and thus the reticle is perfectly crisp) with zero correction at the factory. E. Bryant alluded to this. Of course, you still need to set the Ocular once your mounted the scope to be sure.
Thanks - I appreciate your acknowledgement (even though you resurrected this thread from about 1.5 years back) --wink smiley, I'm glad that you found that old post and that it helped you. You're not alone in that you couldn't get the target and reticle in sharp focus at the same time. I find taking the time to set the Diopter correctly a tedious process (look through the scope, look away from the scope while making a small adjustment, look through the scope again to check the reticle, repeat again and again until the adjustment is perfect). However, once set correctly the Diopter usually doesn't have to be adjusted again unless your vision and/or prescription changes.
Keith
