Re: POA vs POI & Glasses Question
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Twisted .308</div><div class="ubbcode-body">I guess what I'm asking is ..when I shoot I have a hard time seeing the reticule , when I focus in on it and it's clear ..thru the scope the target gets blurry ..if I focus on the target , then the reticule is blurry ..will glasses fix this problem where I can see both at the same time and still work with the scope parallex ?? </div></div>
Sorry for the late reply, but I've been too busy to post much lately. As <span style="font-weight: bold"><span style="font-style: italic">CoryT</span></span> and <span style="font-weight: bold"><span style="font-style: italic">kraigWY</span></span> said, glasses won't fix the problem. The scope's Diopter (aka the <span style="font-style: italic">"Ocular", or "Eyepiece"</span>), is incorrectly adjusted. If your Diopter (aka "Eyepiece" or "Ocular") is set <span style="font-weight: bold"><span style="font-style: italic">correctly for your eye</span></span> the <span style="font-style: italic">reticle</span> should always be in focus regardless of the Parallax setting. Adjusting the Ocular on a firearm/airgun scope is the first thing that should be done after the scope has been mounted and leveled. Unfortunately, over the years here I've seen a lot of people post about how to adjust the Diopter/Eyepiece incorrectly. Sometimes posted and printed procedures are partially correct, but more often than not the procedure is incomplete and/or missing steps, or in the steps are in incorrect sequence (which means the procedure is done incorrectly). Even printed documentation that comes with scopes is sometimes lacking.
As an example, the Nightforce Owner's Manual instructs people to <span style="font-style: italic">"look through the riflescope eyepiece at a light colored background such as a white wall..."</span> This isn't the best way to focus the Ocular / Diopter / Eyepiece because marks and/or objects on the wall can distract the eye. The best way to adjust the reticle is to adjust it <span style="font-style: italic">without distraction</span> 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 <span style="font-weight: bold">THE CORRECT</span> 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.
<span style="font-weight: bold">NOTE:</span> 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). <span style="font-weight: bold">NOTE:</span> 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. <span style="font-weight: bold">Never look at the reticle for more than a couple of seconds when adjusting the eyepiece</span> (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. <span style="font-style: italic"><span style="font-weight: bold">You want to be able to look through the scope and see a sharply focused reticle immediately with your eye relaxed</span></span>. 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 (in effect, your eye will be <span style="font-style: italic">"chasing the focus"</span>).
<span style="font-style: italic">Remember, look away every few seconds and make small adjustments to dial-in the Ocular/Eyepiece focus.</span> Once you have achieved this, you should not adjust the eyepiece at all, <span style="font-style: italic">except to maintain sharp reticle focus</span> as your vision changes over time <span style="font-style: italic">(it always does).</span> 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.
However, if you still cannot achieve simultaneous reticle and image focus after following the above directions for Eyepiece/Ocular Focus, it is <span style="font-style: italic">possible</span> that there is a problem with the scope. That said, it should be noted that <span style="font-style: italic">setting the diopter at the extreme end of it's adjustment range in either direction can affect the image focus.</span>
Also, many people adjust the Parallax setting by continously looking through the scope and turning the Parallax Knob. While this works fine for tactical shooting and hunting, when tighter precision is required fine-tuning the Parallax is preferred. This because the same principle about the eye <span style="font-style: italic">"chasing the focus"</span> also applies to the Parallax setting. This is also why (as long as they're reasonably close), marked parallax knobs are better than non-marked Parallax knobs - even though the markings may only be approximations, the markings provide points of reference and starting points that minimize the time spent looking through the scope while adjusting the Parallax.
In regard to the distances engraved on [Schmidt Bender] PMIIs', <span style="font-style: italic">in my experience <span style="font-weight: bold">and when the Diopter is correctly-set,</span></span> the distance markings are pretty accurate. I've seen people post <span style="font-style: italic">"The numbers on the parallax knob aren't even close"</span> and <span style="font-style: italic">"The numbers are useless"</span>. While its' possible that the calibration on their respective Parallax Knobs is off, maybe these people don't realize that the distances on PMIIs' are marked in <span style="font-weight: bold"><span style="font-style: italic">Meters</span></span>, and that when shooting on ranges marked in <span style="font-weight: bold"><span style="font-style: italic">Yards</span></span> that this must be taken into account and compensated for by setting the Parallax Knob a little shy of the marked settings. This is easily done in 100 yard increments, and pretty easily guesstimated for anything in between. Thats' exactly what I do and I'm almost always very close to where the Parallax Knob needs to be set.
Keith
