Setting up a FFP rifle scope - A simple PSA on Diopters

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bohemr13

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Setting up a FFP rifle scope - A simple PSA on Diopters
03/02/2015 Last edited 03/03/2015 by bohemr13
(9 votes)
[HR][/HR]I recently had a somewhat disgruntled customer return a scope because he complained of it being defective. He sent it back to the manufacturer, the manufacturer told him that it passes all tests and it resolves the 1/16th inch lines at 100yd successfully. No issue.

I told him over the phone how to setup the optic but there was something lost in translation because it didn't fix the problem. Once I opened the return box I knew why immediately.

Now that I think back on it, I'm not surprised at the issue since the comparison optics he mentioned are both SFP units. So, for those that have a FFP scope that may or may not be setup properly, here's a quick method to get you rolling. With a little practice it can be done from soup to nuts in <30 sec.

First and foremost: If you have a First Focal Plane scope, it's less forgiving than a Second Focal Plane scope. Failure to follow through on details will yield issues.


Try this if you're having issues or if you've never setup the diopter and parallax before. I had to figure this out the hard way. I've never seen it clearly spelled in a scope manual that worked. Here's how I do it and the process works.

1) Set to Max Power
2) Parallax set to Infinity (this is very important)
3) Point it at a solid, light background like a white wall or blue sky. You don't want anything except a solid, light color to look at.
4) Start from the diopter all the way into the occular and rotate out.

Don't stare into the optic, open and close your eye as you adjust such that you have no more than about 1 second open, 4-5s closed.

In short order you can get the diopter very closely adjusted such that it will be crisp at all but the finest areas of the reticle.

Once you're there, small adjustments are made and you should focus your attention to the smallest details such as 1/10th mil hash marks, square corners in the reticle, etc.

Flick your eye open, then closed. Look at the reticle picture and see if it's crisp. Repeat as necessary until you have the diopter adjusted properly.

Lock down the ring on your diopter or wrap it with electrical tape and lock it down. Perhaps a sharpie with a witness mark between the occular and diopter ring. Something to reference it for the inevitability that it will get bumped.

Following these steps would have saved this gentleman significant frustration and hassle, as well as avoiding some of the bad information being circulated about some of the new scopes on the market.
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talivXGunny Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA
03/02/2015
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i'm confused. how could you tell immediately by looking at the scope that the diopter wasn't adjusted?

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Captramrod01

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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
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I'm guessing the diopter was all the way in or out. Pretty uncommon setting for pretty much anyone. That , or he quickly focused it for him and the scope was fine?

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lennyo3034XFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
[HR][/HR]Thanks for this write up, I recently started doing this to good success. I find taking it outside and looking at the sky better than looking at a wall. I used to set it "all the way in" as it would give me a clear enough reticle. However what I noticed was that if I stared at the crosshairs for a long time, the target would get blurry as my eye had adjusted to the reticle. After using this method, I can stare at the crosshair for longer without the target getting blurry.
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6x47SteveXFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
[HR][/HR]It's kind of funny in a way/ more so sad, because over the last few years every novice and even extending to most shooters I've met at the range have had no idea that the diopter can be adjusted, LOL ?!?

Doesn't anybody read instructions anymore???
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skinman3834XPrivate
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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
(1 vote)
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I have a buddy whose father wrote software for john deere. He would get calls all the time from people trying to use the software.

He called these people RYFMS. Read Your F@#$% Manual. LOL

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bohemr13

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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015 Last edited 03/03/2015 by bohemr13
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taliv wrote:
i'm confused. how could you tell immediately by looking at the scope that the diopter wasn't adjusted?​
The parallax knob was set ~ 1/4 of the way between 100 and 200yd.

When I spun the parallax to infinity, rotated the diopter about 1/2 turn it turned crystal clear all the way to the edges of the scope picture instantly.

6x47Steve - I agree though this was not the case. The manual that comes with the scope is translated poorly from German. This is purely the fault of the manufacturer... ESPECIALLY because they just ripped off the old manual from a different scope and threw it in the box with the new one.
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LukeNCMXXSergeant
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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
(1 vote)
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Change the title so it mentions diopter adjustment and then sticky this please.

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USALTC

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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
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Excellent. Reads just like the instructions from Nightforce that came with my F1's.

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RthurDXFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/03/2015
(1 vote)
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Good psa Bohem. I had to deal with this very problem recently.







R

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SPAK7XFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/03/2015
[HR][/HR]Great post! Found this to be exactly true on my t5xi steiners...I thought initially I had clarity and Chromatic abberation issues, but when I finally got the diopter set CORRECTLY all those issues went away. Thanks for posting bohem.
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Diver160651

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Re: Setting up a FFP rifle scope - A simple PSA
03/03/2015
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Diver160651 wrote:
whats a diopter?​
Crap now that someone is making this a sticky, I am going to remove my transparent attempt at a joke..

It would be good if the OP of the PSA explain why the first focal plan (that changes magnification with the target) is more critical to adjustment than a SFP.



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lennyo3034XFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA
03/04/2015
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Diver160651 wrote:
Diver160651 wrote:
whats a diopter?​
Crap now that someone is making this a sticky, I am going to remove my transparent attempt at a joke..

It would be good if the OP of the PSA explain why the first focal plan (that changes magnification with the target) is more critical to adjustment than a SFP.

Good point. My guess is that you're focusing the reticle and obviously the reticle is in a different location on FFP and SFP. I would like a deeper explanation as to why it's more critical for FFP though.

I have noticed my SFP scopes are more forgiving of diopter setting.
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bohemr13

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/04/2015 Last edited 03/04/2015 by bohemr13
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[HR][/HR]Whomever asked: The optic in question was a T5Xi 5-25.

FFP is more sensitive due to the location of the reticle in the optical stack. Small errors are more sensitive and the issues are magnified.
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cowholyXFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/06/2015
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Would you use the same steps for a SFP scope?

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bohemr13

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/06/2015
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[HR][/HR]I do. Unless you have clear instructions from the manufacturer stating something different this is a good method to start with.
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TRH1962XCorporal
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/06/2015
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3) Point it at a solid, light background like a white wall or blue sky. You don't want anything except a solid, light color to look at.



From No .3: Can I do this at any distance in my home? Say like from 15ft away from the wall adjusting the diopter?

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bohemr13

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/07/2015
(2 votes)
[HR][/HR]Yes, the goal is focusing the diopter. You're not trying to focus the wall, you just want the reticle to be crisp.

Parallax at infinity is important.

I find it works best on a blue sky but you can do it indoors.
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jeo556XSergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/10/2015
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Thanks for the walk through, I followed a different and less straightforward procedure that left me wondering if I had it as good as can be. Illness doing this tonight.

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snubbieXPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/12/2015 Last edited 03/12/2015 by snubbie
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bohemr13 wrote: Yes, the goal is focusing the diopter. You're not trying to focus the wall, you just want the reticle to be crisp.

Parallax at infinity is important.

I find it works best on a blue sky but you can do it indoors.​
I tried this method and found if I optimized the diopter/reticle setting for max magnification and max parallax (as per instructions above), the rest of the magnification range (the reticle) was out of focus by 1/4 turn on the diopter. Backing off the diopter by 1/4 turn the entire magnification range preserves the reticle's focus (but not as crisp as it originally was at the highest magnification). Is this normal for this procedure ?
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dondlhmn

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/12/2015
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What amazes me is that so many shooters have absolutely NO IDEA that the diopter on the "eyeball end" of a scope is to bring the RETICLE ONLY into good, clear and sharp focus for them and then the "parallax adjustment", whether it be around the objective lens or a side mounted knob, is for use at varying distances and HAS NOTHING TO DO WITH THE FOCUS OF THE RETICLE!!! What they need to do is to focus the reticle and then LEAVE IT ALONE. It may require changing when the scope is used by a different shooter with different vision than the first shooter or when the shooter encounters. over time, some kind of a change to his vision, but SHOULD NOT REQUIRE any fiddling if the original shooter has once set it correctly when they first receive it and put it into use and then his/her vision does NOT CHANGE.

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snubbieXPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/12/2015
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dondlhmn wrote:
What amazes me is that so many shooters have absolutely NO IDEA that the diopter on the "eyeball end" of a scope is to bring the RETICLE ONLY into good, clear and sharp focus for them and then the "parallax adjustment", whether it be around the objective lens or a side mounted knob, is for use at varying distances and HAS NOTHING TO DO WITH THE FOCUS OF THE RETICLE!!! What they need to do is to focus the reticle and then LEAVE IT ALONE. It may require changing when the scope is used by a different shooter with different vision than the first shooter or when the shooter encounters. over time, some kind of a change to his vision, but SHOULD NOT REQUIRE any fiddling if the original shooter has once set it correctly when they first receive it and put it into use and then his/her vision does NOT CHANGE.​
Are you saying the procedure outlined above for the initial setting of the diopter/reticle focus is irrelevant ?
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dondlhmn

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/12/2015 Last edited 03/12/2015 by dondlhmn
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snubbie wrote:
Are you saying the procedure outlined above for the initial setting of the diopter/reticle focus is irrelevant ?​
Of course not. Was I somehow not clear enough that I gave you that idea? My apologies if I did. Did I say or imply that it is irrelevant? NO........Let me explain this AGAIN........EACH SHOOTER that uses that scope has to set the diopter up to match their vision and if NOT set up, the reticle will likely be out of focus FOR THAT PARTICULAR SHOOTER DUE TO HIS/HER vision specifics.THEN, if another shooter uses it, the reticle may be out of focus for that NEXT SHOOTER unless they set it up/focus it again to meet their OWN EYES' differences from the first shooter's eyes. SIMPLE, NOT COMPLICATED!!!!

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snubbieXPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/12/2015
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dondlhmn wrote:
snubbie wrote:
Are you saying the procedure outlined above for the initial setting of the diopter/reticle focus is irrelevant ?​
Of course not. Was I somehow not clear enough that I gave you that idea? My apologies if I did. Did I say or imply that it is irrelevant? NO........Let me explain this AGAIN........EACH SHOOTER that uses that scope has to set the diopter up to match their vision and if NOT set up, the reticle will likely be out of focus FOR THAT PARTICULAR SHOOTER DUE TO HIS/HER vision specifics.THEN, if another shooter uses it, the reticle may be out of focus for that NEXT SHOOTER unless they set it up/focus it again to meet their OWN EYES' differences from the first shooter's eyes. SIMPLE, NOT COMPLICATED!!!!​
Thanks for the clarification. I was trying to discern if your post was a response to a specific post or the instructions.
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Thrust911

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/19/2015
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Good stuff! I Appreciate you putting the information up for folks.

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SHootSTraight22XSergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
04/15/2015
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I thought I had this down pat but I guess not. I've always done it this way but didn't relies the focus needed to be set to infinity. I've been setting mine shooting groups at 100yds or on white steel at 727yds.. The cross hairs are perfect black and on the same plane with the targets but since I wasn't setting focus to infinity could this be why I shoot .2-.3 groups some days and 1in groups the next with 1 flier round making them 1 inch?? Even the 1moa 100yd groups have two shots bugholing or .3 max but there are the unexplained fliers off to one side.. I was wondering if my cross hairs were slightly dancing from my head not being anchored exactly the same every shot. Kind of like using a peep site on a bow and not using one. With a bow though it's easier I might add to keep the same anchor point under the jaw line for me but if the scope isn't properly adjusted I'm wondering if slight movements left right up and down with my head could be causing 1 inch movements at 100yds with the center of my cross hairs?? Is that it?

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nogunjoe

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/02/2015
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ATACR F1 synchronizing the Parallax, Focus and Diopter



An alternative method.
 
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mrshooter

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/11/2015
[HR][/HR]I'm about to set one up myself. Thanks for the info
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Ironman308

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/13/2015
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Thank you for the post. I just received my first FFP scope today so I will try out this procedure.

Cheers,

Jim

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tozz4754XSergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/26/2015
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of course not. was i somehow not clear enough that i gave you that idea? my apologies if i did. did i say or imply that it is irrelevant? no........let me explain this again........each shooter that uses that scope has to set the diopter up to match their vision and if not set up, the reticle will likely be out of focus FOR THAT PARTICULAR SHOOTER DUE TO HIS/HER vision specifics.THEN, if another shooter uses it, the reticle may be out of focus for that NEXT SHOOTER unless they set it up/focus it again to meet their OWN EYES' differences from the first shooter's eyes. SIMPLE, NOT COMPLICATED!!!!​
SPOT ON.....THANKS
 
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jsthntn247XFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/29/2015
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Thanks for posting this, had no idea a ffp differed froma sfp. One question. I looked at the sky with my focus on infinity and noticed when I moved the diopter the reticle would come out and in as if I was adjusting the power setting. Is this normal and what should I be looking for, I couldn't see much difference in clarity. Bushnell 4.5-30x50 EXRS.

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FourT6and2

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/31/2015 Last edited 05/31/2015 by FourT6and2
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And what if the scope in question has no parallax adjustment? Do we adjust diopter while looking at the sky (infinity) or do you set while looking at a plain background at the scope's fixed parallax-free range (which is usually something like 100 yards/meters to infinity)?

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Scurvydogg

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
05/31/2015
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tag

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Matthew2112XPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
06/14/2015
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Is a FFP more sensitive to differences in the shooter's prescription changes? I shoot with glasses of one prescription and contact lenses of another. This is significant with iron sights, but my SFP seems to handle it fine. If I want to let others use my rifle or if I want to move between prescriptions then would a SFP be a better choice for my next purchase?

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750k2XSergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
06/22/2015
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What about a fixed 36X used for rimfire @ 50yds - should you still set with parallax at max??

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DGD6MMXSergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
07/31/2015
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I am glad I read this, you made it easy to understand and set that even a dumb concrete finisher can do it

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hals1XPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
08/08/2015
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If you do not have the range adjustment set properly, there is a definite possibility of parallex error--move your head and the reticle/target alignment changes.​
SHootSTraight22 wrote:
I thought I had this down pat but I guess not. I've always done it this way but didn't relies the focus needed to be set to infinity. I've been setting mine shooting groups at 100yds or on white steel at 727yds.. The cross hairs are perfect black and on the same plane with the targets but since I wasn't setting focus to infinity could this be why I shoot .2-.3 groups some days and 1in groups the next with 1 flier round making them 1 inch?? Even the 1moa 100yd groups have two shots bugholing or .3 max but there are the unexplained fliers off to one side.. I was wondering if my cross hairs were slightly dancing from my head not being anchored exactly the same every shot. Kind of like using a peep site on a bow and not using one. With a bow though it's easier I might add to keep the same anchor point under the jaw line for me but if the scope isn't properly adjusted I'm wondering if slight movements left right up and down with my head could be causing 1 inch movements at 100yds with the center of my cross hairs?? Is that it?



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asimon78XPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
09/05/2015
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Good info. Thank you for sharing!

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47roninXPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
09/05/2015
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Thanks for this post. Saved me some headaches.

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Shanerbanner10XFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
09/15/2015
[HR][/HR]Not sure if this has been said yet, but everyone's eyes are a touch different so most peoples will be a hair different.
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Baer45X83 MONTHS
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/01/2016
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Thanks!

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CharlieNCXGunny Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/17/2016
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On both my Sightron FFP and SFP scopes I did not close my eye to de-focus when setting the eyepiece and ended up with significant horizontal parallax, but surprisingly none in the vertical. This had not made a difference on other brands, but it bit me in the ass big-time on these. Do not shortcut this step.

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RoninISCXCorporal
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/22/2016
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very helpful.

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rymart

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
03/21/2016 Last edited 03/21/2016 by rymart
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My eyes must be retarded because on two different FFP scopes I can turn the diopter round and round and round and the rectical looks the same every time I look at it (In focus, not quite perfectly crisp, but very, very close). I literally turned the diopter all the way in (about 4 revolutions) and it looked the same as where I started. I'm following all of the advice here... Max magnification, parallax at infinity, looking away for 2 - 10 seconds, then quickly looking in the scope view... I tried swiping views of the scope with rests in between.

It almost seems like my eyes are adjusting to/focusing the rectical almost immediately.

Any ideas what to do here? Could I get someone with similar vision (20/20 corrected) to adjust it for me?

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JMcE42

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
04/25/2016 Last edited 04/25/2016 by JMcE42
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I am in a similar situation. I have 20/20 or 20/10 vision (depending on if the eye doc decides to have me read that line lol) I have a Vortex Viper PST. I start with the diopter all the way in and I can't tell a difference in the reticle until its most of the way out it starts getting fuzzy. I was thinking the same thing that my eyes are just focusing too quickly to see any difference.

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Ericbc7XPrivate
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
07/03/2016
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I wear no-line bifocals. Small changes in my head position has me viewing the reticle through a slightly different combination of optics on every position change. If my diopter is set for the bench, I expect it's different in prone. Do I need to get single vision lenses for shooting? That will make seeing the turret numbers difficult...

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JWG223XCorporal
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
08/19/2016
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How do you set diopter for a SFP scope, and for what distance should you set it? If I set diopter for 100 yards, 200 yards is imperfect looking. If I set it on 1x for targets up close, it does poor at 100 yards, and vis-versa at 100/max magnification vs. up close. In short, I have found that perfect diopter settings are very distance-specific with my SFP optics.

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readyalpha1XCorporal
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
12/11/2016
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Ericbc7 wrote:
I wear no-line bifocals. Small changes in my head position has me viewing the reticle through a slightly different combination of optics on every position change. If my diopter is set for the bench, I expect it's different in prone. Do I need to get single vision lenses for shooting? That will make seeing the turret numbers difficult...​
You need single vision lenses but you can set the diopter for whatever glasses you have on, or none at all. I need 2.0 reading glasses to read and usually wear 1.75's all the time. However, I can set the diopter for no glasses, the 1.75's or the 2.0's. It really doesn't matter. Just adjust the diopter accordingly. I usually have mine set for no glasses and have a pair laying on the bench when I need to see up close for adjustments or such.

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ColdTriggerFinger

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
12/16/2016 Last edited 12/16/2016 by ColdTriggerFinger
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JMcE42 wrote:

I am in a similar situation. I have 20/20 or 20/10 vision (depending on if the eye doc decides to have me read . I was thinking the same thing that my eyes are just focusing too quickly to see any difference.​
Enjoy it while you have it !!
When you shoot iron sights /pistol, can you clearly see the front sight ?

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SHGMAC

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/10/2017
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bohemr13 wrote: ...With a little practice it can be done from soup to nuts in <30 sec....​
I do the same process as you, and it's the first thing I do. This is a great little PSA, and one that I see overlooked consistently at the local gun club.

This is where I got my process from (Video at 2:10). Later on he explains the maximum parallax impact for a given distance (Video at 5:00).



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SHGMAC

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/10/2017
(2 votes)
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JWG223 wrote:
How do you set diopter for a SFP scope, and for what distance should you set it? If I set diopter for 100 yards, 200 yards is imperfect looking. If I set it on 1x for targets up close, it does poor at 100 yards, and vis-versa at 100/max magnification vs. up close. In short, I have found that perfect diopter settings are very distance-specific with my SFP optics.​
I would agree w/ the OP's take on it. Adjust the objective (usually in the form of a side focus dial) to infinity and then dial in the diopter adjustment while looking at a blank image.... lock it down. I haven't found that my diopter setting is target-distance dependent.

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SHGMAC

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/10/2017
(2 votes)
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Ericbc7 wrote:
I wear no-line bifocals. Small changes in my head position has me viewing the reticle through a slightly different combination of optics on every position change. If my diopter is set for the bench, I expect it's different in prone. Do I need to get single vision lenses for shooting? That will make seeing the turret numbers difficult...​
Man, that's a tough one. Smooth transition bifocal glasses would mean that you would be changing your diopter the lower you look through your glasses. Not sure how to get around that, but I'm interested if someone has a solution.

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lashlaroe

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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
01/11/2017
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I wear no-line trifocals. With practice, dry firing and otherwise, I've found a relatively common cheek weld that works in most positions without much difficulty. I do however, have the most trouble with weak side shooting because of this restriction. It's doable but not comfortably nor as quickly as shooters without corrective lenses.

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FalarXFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA
Yesterday at 12:42 PM
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Captramrod01 wrote:
I'm guessing the diopter was all the way in or out. Pretty uncommon setting for pretty much anyone. That , or he quickly focused it for him and the scope was fine?​
It seems my eye can't tell much of a difference from full closed to about 1/3 of the way out on most scopes.

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lashlaroe

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Re: Setting up a FFP rifle scope - A simple PSA
Yesterday at 3:16 PM
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Falar wrote:
Captramrod01 wrote:
I'm guessing the diopter was all the way in or out. Pretty uncommon setting for pretty much anyone. That , or he quickly focused it for him and the scope was fine?​
It seems my eye can't tell much of a difference from full closed to about 1/3 of the way out on most scopes.​
Some scopes have a more forgiving Diopter setup than others. I imagine it has to do with the specific prescription of the glass. My Sightron was very forgiving and allowed a pretty large spread for a good diopter setting and also a forgiving parallax prescription. My Steiner T5Xi, as one of the early ones, had a very difficult diopter. It took me five lengthy sessions to get it just right for my eyes. The new and repaired ones are better.

And then it also has a lot to do with your eyes and prescription.



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FalarXFirst Sergeant
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Re: Setting up a FFP rifle scope - A simple PSA on Diopters
Yesterday at 5:08 PM
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I just received a S&B 3-20 US and almost thought I must be doing something wrong. Clearly at all the way out I couldn't see shit, so I started with it all the way in. It looked pretty damn good and I picked a white wall to look at, parallax to infinity, etc like the OP says and as i backed it out I had a really hard time deciding if this 1/4 turn was better than that or whatever.

In the end I ended up maybe....1/4 of the way out. The index dot lines up perfectly with the S/N on the bottom of the eyepiece so it will be easy to always check for movement. It reminds me of getting my eyes checked and how I actually failed a test once with 20/16 vision....when someone shows you 7 lenses all in a row and all look great its hard to pick which one is better.
 

rideHPD

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#7
So there are some fun things to comment on, hopefully the original commenters inside the copy/paste section come back.

1) The process is the same whether or not you have parallax adjustment, the distance away from your blank background does not matter. All that matters is that there is no detail your eye can resolve to distract it from the reticle and that it is bright so that there is enough light transmission to form a clear image of the reticle. The only difference with scopes that have no parallax adjustment being that you should make an extra effort to ensure the reticle is perfectly centered when you do this, with sharp, black edges, and no shadowing or darkness around any edges. If you can't get rid of that, adjust the scope placement on the rifle. That also brings up the point that this is so much easier to achieve when mounted to a rifle or fixed object. If the scope is moving around you have no hope to really achieve this, these are such fine adjustments that are already hard for the eye to discern without the scope moving at all. The sky is really a horrible thing to look at, get a piece of printer paper and stare at that if you have to.

2) The distance that you then shoot at makes no difference. Something that should be mentioned is that it is common for scopes to not perfectly focus the target plane when the parallax is properly adjusted, or at least that was a thing not too long ago. Always check your parallax to make sure there is no movement in the reticle a la your POA, don't simply adjust it till focused. Additionally, the distance markings don't exactly correlate with the distance the parallax is removed at (nor is your margin of error in ranging smaller than that of the parallax minimization). The diopter adjusts focus, so if it isn't perfect it's not the end of the world (unless it also collimates out-of-center rays, still not that big of an issue if you don't have parallax). Don't adjust for focus at the cost of parallax which may screw with your POA. If you only shoot at one distance you could adjust the diopter to bring the reticle and target into best focus with the parallax dialed out, but that would be a bit more advanced, and you're likely to forget that you've done as such if you then randomly shoot anything else. And you likely won't realize that's the issue. If you shoot weird groups that you can't explain, start here. Frank's shooters checklist is probably the best thing for those learning the fundamentals. Check your parallax, check your elevation, check your windage, check your NPOA. Leave the target, reset everything back to zero/default. Going to a new target check everything again. Once you get into the habit you won't wonder how the hell you shot a .3 MOA group at 300 yards and a 2.3 MOA group at 100. Parallax becomes a bigger issue the closer your target is, so if you don't adjust it you may very likely think you have magic bullets.

3) Really would like to hear more about the magnification adjustment changing reticle focus, I imagine that's a SFP scope? I'm too tired to visualize the ray diagram but my first guess if it's not from eyes/perception is that the magnification adjustment doesn't track right on the high end and it's creating an abberation if it's just at the very high end. Maybe the outer edge of the lens is no longer meeting the next lens plane and being removed from the image, something like that. More likely I think that's just an improper perception of the reticle, I know it happens to me with some scopes. My old NXS 5.5-22 is a bit hard to resolve the entire image.
 
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Aug 12, 2011
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#9
Great advice to get things started!

Does anyone else make fine adjustments to their diopter when out in the field doing static, slow long range shooting? I've noticed that with my more "contrast-y" scopes, I can actually improve the res and pull the image out just a tad more by adjusting the diopter.
After the adjustments you made in the field, how if any does that effect any other distance than the one you made the fine adjustment to?
 

diverdon

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Dec 21, 2011
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#10
Great advice to get things started!

Does anyone else make fine adjustments to their diopter when out in the field doing static, slow long range shooting? I've noticed that with my more "contrast-y" scopes, I can actually improve the res and pull the image out just a tad more by adjusting the diopter.
If my understanding is correct what you are seeing means---

1) that is because your diopter was incorrectly set in the first place.

or

2) There is something wrong with your scope.

or

3) you are just doing it wrong.

Again unless I am wrong you adjust the diopter to make the reticle sharp---adjust the paralax to make the target sharp.
 
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diverdon

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Dec 21, 2011
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#11
Could be that this one was just a hair off when initially set, or my eyes reacted a little different out in the field... Either way, i'll chalk it up to user error since nobody else is experiencing this.
If that is what you want then that is fine, they are your hits and misses. If you are striving to bee the best shooter you can be, consider going back to the start of this thread and following the procedure to set your diopter until you have enough confidence in the setting that you don't adjust it in the field. In the field you set the parallax.