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Rifle Scopes Diopter adjustment help

JohnDeereGuy1996

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Minuteman
Feb 13, 2017
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I’ve read all the pinned post etc and while very helpful I’m having some issues still or at least I think so?

Last time I got my eyes check (10 years ago) I had 20/15 vision so I’m hoping it isn’t my eyes.

When adjusting the diopter on pretty much any scope I find that I have an extremely wide range where the reticle looks crisp with no real change while making adjustments. Is this normal? I’ve tried max mag and a lower magnification while adjusting.

I also tested my parallax earlier on a 4-16 atacr with putting the rifle in a solid rest and moving my head side to side and up and down. Through the whole diopter adjustment range where I could see the reticle crisply the cross hairs seemed to move.

Any pointers or tips would be much appreciated. Honestly may just be my ocd trying to get it absolutely perfect.

Thanks!
 
Parallax to infinity, maximum magnification, look at the sky (blue or gray), and set diopter from there.

Don't look too long because your eyes will adjust.

I tend to look, look awake, look again. Walk away for a new minutes and repeat.
 
I have the same issue. My eyes are strong enough to rapidly compensate and give instant crisp clarity on a decent range of diopter settings. The post above is exactly how I initially set it. But on a seperate range day, I will try to run that optic for a few hours on high mag to intentionally fatigue my eye. If it starts to get fuzzy, I fine tune once tired.
 
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I’ve read all the pinned post etc and while very helpful I’m having some issues still or at least I think so?

Last time I got my eyes check (10 years ago) I had 20/15 vision so I’m hoping it isn’t my eyes.

When adjusting the diopter on pretty much any scope I find that I have an extremely wide range where the reticle looks crisp with no real change while making adjustments. Is this normal? I’ve tried max mag and a lower magnification while adjusting.

I also tested my parallax earlier on a 4-16 atacr with putting the rifle in a solid rest and moving my head side to side and up and down. Through the whole diopter adjustment range where I could see the reticle crisply the cross hairs seemed to move.

Any pointers or tips would be much appreciated. Honestly may just be my ocd trying to get it absolutely perfect.

Thanks!
You’ve received great advice.

Might want to check this out from March on this subject

 
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They make an interesting point in the Q&A section of the March link about adjusting diopter on a low magnification setting. Maybe that's right, and I'm wrong. I should clarify why I do it how I do it:

I'm generally only messing with the diopter during initial setup. I use the highest magnification because I am continually getting on-gun to grab a new snap sight picture of the (hopefully clear) reticle, and therefore I also get to check that I have set the eye relief at a repeatable, unshadowed distance (plus cheek rise, LOP fitment, etc). If I have to break out tools and adjust that, I'd rather do it before everything else gets tuned up.

Using higher magnification during a long confirmation run is just to wear myself out faster. On say a 25x optic, I'd normally sit around 15x for use. But if the diopter is in fact adjusted well, I can generally run that a long time and still see the minor details of a busy reticle (FFP mostly). When I run it up to 25x, I do find I'm looking much harder on mirage reads, target edges, milling stuff just because, and I will note the fatigue when I come off gun...not from the reticle but from the target view. Once tired: If the diopter setting is poor, it will all turn mushy as I adjust out parallax. If its good, then the reticle is still clear even when my eyes are tired of looking and the target out of focus.

If you've a correctly set ocular/diopter (and are leaving it set/no longer messing with it), but you're not able to adjust parallax out, maybe that lense cell is stuck or adjustment knob not working?
 
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Put the magnification close to min, turn on the illumination, go inside a dark room, adjust the diopter until the reticle is crisp. Put the magnification on high and make sure it’s crisp. That should do it.
 
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Put the magnification close to min, turn on the illumination, go inside a dark room, adjust the diopter until the reticle is crisp. Put the magnification on high and make sure it’s crisp. That should do it.
This is an interesting take. I’ll try this as well.
 
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What is important is to not have anything in the background that your eye will focus on. So putting a sheet of paper in several inches in front of you scope or aiming at a blank wall will do the trick. Aiming at the sky is another, but if there are clouds, that could be an issue. You want the lowest magnification to get the most light to the reticle. Unless you illuminate your reticle all the time, you do not want to light the reticle as that may bring other issues; you want to focus only on the plain reticle.
 
Since I have such a broad range where the reticle is crisp does this mean I have a broader range of not having parallax
 
Since I have such a broad range where the reticle is crisp does this mean I have a broader range of not having parallax
No. It means you're probably a younger person with great eyes that adjust easily. To refine the diopter setting, you might want to take VERY QUICK peeks at the reticle and will probably be very happy with the diopter set at or near 0.

The diopter setting has nothing to do with parallax or depth of field.
 
No. It means you're probably a younger person with great eyes that adjust easily. To refine the diopter setting, you might want to take VERY QUICK peeks at the reticle and will probably be very happy with the diopter set at or near 0.

The diopter setting has nothing to do with parallax or depth of field.
I meant the parallax you can get with your reticle when your diopter is set incorrectly.
 
Put the magnification close to min, turn on the illumination, go inside a dark room, adjust the diopter until the reticle is crisp. Put the magnification on high and make sure it’s crisp. That should do it.
What he said.
 
This explains it better then I can lol
No. I don't understand that you're not confirming or infirming my answer to you first main question. You asked if it was normal, and I hazzared a guess about why it would be normal and you ignored it.
 
No. I don't understand that you're not confirming or infirming my answer to you first main question. You asked if it was normal, and I hazzared a guess about why it would be normal and you ignored it.
I’m not ignoring anything. I believe you’re misunderstanding what I’m trying to ask. It’s hard to convey through text. Which is why I posted the video about the head movement .
 
I’m not ignoring anything. I believe you’re misunderstanding what I’m trying to ask. It’s hard to convey through text. Which is why I posted the video about the head movement .
I meant the parallax you can get with your reticle when your diopter is set incorrectly.
Parallax is independent of the diopter, two different things. So your question doesnt make any sense.
 
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Parallax is independent of the diopter, two different things. So your question doesnt make any sense.
Yes I realize they’re two different things. But when doing the head movement test everyone always says to fine tune the diopter if your cross hairs move with your head. If it moves then this means they aren’t on the same plane correct?
 
Yes I realize they’re two different things. But when doing the head movement test everyone always says to fine tune the diopter if your cross hairs move with your head. If it moves then this means they aren’t on the same plane correct?
No they dont. They say to do the opposite.
When you have the target and reticle on two different focal planes you can observe the parallax. To tune out the parallax you adjust the parallax wheel; be it on the side, top or objective. None of that has to do with the diopter.
If you are talking about what he said at 2:36 in the video you shared, hes saying its all set up wrong and to start over, not that the diopter itself adjusts parallax but that its incorrectly focusing right when parallax is still wrong.
 
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No they dont. They say to do the opposite.
When you have the target and reticle on two different focal planes you can observe the parallax. To tune out the parallax you adjust the parallax wheel; be it on the side, top or objective. None of that has to do with the diopter.
If you are talking about what he said at 2:36 in the video you shared, hes saying its all set up wrong and to start over, not that the diopter itself adjusts parallax but that its incorrectly focusing right when parallax is still wrong.
Thank you…this thread was starting to hurt my head.
 
There's no such thing as 2 different focal planes when U look thru any optic; there's only one plane of focus or the sharpest point of focus and objects "fairly sharp" in front of and behind this plane of focus, which is what U call the hyperfocal distance.

There are different points of focus but only one point of sharpest focus.

The diopter is to adjust your vision to the scope w/no detail except the reticle, so the combination of your eyeball and the scope can focus properly, but after that's done, then as Denys explained in another discussion moving your eye off the centerline optical axis of the scope along w/not having the plane of focus on the target (or reasonably close) is going to be a problem.
 
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There's no such thing as 2 different focal planes when U look thru any optic; there's only one plane of focus or the sharpest point of focus and objects "fairly sharp" in front of and behind this plane of focus, which is what U call the hyperfocal distance.

There are different points of focus but only one point of sharpest focus.

The diopter is to adjust your vision to the scope w/no detail except the reticle, so the combination of your eyeball and the scope can focus properly, but after that's done, then as Denys explained in another discussion moving your eye off the centerline optical axis of the scope along w/not having the plane of focus on the target (or reasonably close) is going to be a problem.
And to fix that you’d need to adjust with the parallax knob?
 
This is one of those subjects where it's harder to explain than it is to understand.


You've already gotten several variations (good ones), but they're not "clicking" 4 U. There are 2 separate issues and that may be part of the confusion.

The white paper/sky/wall is focused in a way so as to make the background behind the reticle absolutely featureless/devoid of any detail, leaving only the detail of the reticle U can make out. You adjust the diopter until the reticle appears sharp Bcuz that will be the only detail you'll be able to see.

The combination of your eyeball and the optic can then focus on anything.


After that's been addressed, it's a matter of where your focus is in relation to the target and everyone has said essentially the same thing which is also what the video is saying which is move your eye around, and if the reticle moves off target U have a problem w/parallax.

Adjust the Diopter 4 your eyesight so U can focus the scope properly.

Adjust the parallax knob if U move your eye off center @ the back of the scope and the crosshairs move off target.
 
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I appreciate all the solid info. I believe everyone has got me straightened out in my confusion. Thanks again everyone.

With that said. The reticle still appears super sharp to me for half the diopter range. I guess my best chance is just set around zero and then make small tweaks if I start experiencing eye fatigue?
 
What optic is the primary one in question?

I guess its mechanics could allow more rotation with less actual diopter change (like a euro fast adjust versus a locking ocular piece with really fine threads), so it seems like you're turning alot but actual adjustment is small...or alot.
 
What optic is the primary one in question?

I guess its mechanics could allow more rotation with less actual diopter change (like a euro fast adjust versus a locking ocular piece with really fine threads), so it seems like you're turning alot but actual adjustment is small...or alot.
I run mostly Nightforce atacr with a few leupold and nx8 sprinkled in.
 
Let’s just say if every optics was +2.5 to -2.5 on the diopter setting. The reticle looks the same to me from 0.5 to -2.5 with the diopter all the way screwed in.
 
Since the subject is focusing the reticle, can someone please tell me why ALL scopes don't have locking diopters? I must have been lucky that the very few scopes I owned had them so once the reticle was focused, I could lock it and not worry about it. In fact, when shopping for a new scope, it never occurred to me to consider whether or not it had it. Now I just bought a relatively expensive scope for my precision rimfire rifle, and it has a "fast focus" feature which really means a very loose, non-locking diopter which is always moving, and it's a real pain in the neck.

Are there any Pros to having a non-locking eyepiece? Other than cheaper to manufacture?
 
No lock, no matter what U do it's going to move. What I did on a couple of my older optics was cut a small sliver of metal adhesive tape,(whatever the hell they call it) and tape it across, and I haven't budged/moved/bumped/shifted the diopters since.

I wouldn't do that on a brand new/expensive optic cuz I'd keep thinking about the residue from the adhesive.


Years ago I bought a Eotech G33 magnifier, didn't want to tape it in place so I killed two birds w/one stone and got this stuff.


Perm-Inkcopy4w.jpg



It looks like a cheap "marks-a-lot-pen", but it's permanent ink. I use it to renew the white on the sights of my handguns/long guns.

You push in lightly against whatever U want this on, and it's on permanently.

My Eotech G33 was new, so I used this to deposit a nice small dot on both sides of the diopter and it looks like it might've come from the factory that way. U gotta have a light touch w/this stuff cuz it'll make a mess quick so if you ever use it, I'd suggest practice a couple of times on something you don't care about.

I think I've moved the diopter on the G-33 by accident once, and simply lined up the two dots next to each other so it was back to where I had it.


The bezel U twist @ the back of the G-33 to adjust the diopter is way smaller than the rubberized housing just in front of it at the back, so taping across that was going to look so ratty that I put a small white dot @the back of the rubberized housing, and matching white dot on the bezel where my eyesight is.


I don't think it's too much to ask the manufacturers that if you're not going to provide a way of locking the diopter, at least make it stiff so it's harder to budge.




DLevel-New-Years4-WEB.jpg






When I renew one of my sights, a drop is too much, maybe a tenth of a drop is perfect to make the white on a sight pop like it was when it was new.

So maybe this will give U ideas.



BTW: On some of my sights, they were so small, I had to use a toothpick to depost the ink on the sight to make it look right.
 
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Shot the other side of the G33 w/my reference mark.

So after rotating the Bezel/getting the optic adjusted for my eyesight, I practiced 3 times leaving a "white dot" on some scrap metal in my basement shop.



So in the case of my G33 I placed the reference dot opposite the "h" of the emobssed "Eotech" lettering.

Left it alone for 2 days and the ink is hard as a rock.




BZFV4W.jpg
 
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Shot the other side of the G33 w/my reference mark.

So after rotating the Bezel/getting the optic adjusted for my eyesight, I practiced 3 times leaving a "white dot" on some scrap metal in my basement shop.



So in the case of my G33 I placed the reference dot opposite the "h" of the emobssed "Eotech" lettering.

Left it alone for 2 days and the ink is hard as a rock.




BZFV4W.jpg
That will work great, as long as it doesn't make a full rotation out of focus...
:)
 
I'd say the options are...

1 Tape it.
2 Mark it.
3 Sell it.

Number 3 (getting rid of it) is what I go for when I pay a lot money for something which gives me nothing but headaches, and that goes for women, cars, guns, cameras, scopes...... Bcuz who needs a "pain in the neck".

Good luck.
 
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