Rifle Scopes What magnification do you set focus/diopter with...

[Danattherock]

Ahead of the arrival of my ZCO 527 today on the brown truck, I was researching this subject a little bit in an effort to get the most out the optic.

I heard ZCO recommends setting the focus at the lowest magnification within the range. I had previously been told the opposite and to use max magnification with a white wall background the common advice.

Dark lord of optics YouTube channel, Ilya if I'm not mistaken, made a very thought-provoking video covering this subject. The gist of it, adjust the focus of the reticle at the magnification you most commonly intend to use the optic. That would be 15-18x for me, where I'm at 80% of the time in PRS matches. In almost four years of precision rifle shooting, I can honestly say that I've never even thought about this.

So what say you, what is your preferred magnification and or method of setting your eyepiece focus/diopter?

And thanks Ilya for opening my eyes, and helping them focus, lol...


Dan




He gets into it directly at the 17:30 mark..

 

[Dthomas3523]

I’d set it at lowest like they recommend. If it doesn’t work for you in your preferred magnification range, then set it at that and tweak.

I’d lump this in with stuff that doesn’t matter exactly how you do it in the end, as long as the reticle stays in focus for you once you’re done.

 

[Danattherock]

Yeah I was under the same impression until I watched the video and he explains how FFP optics present certain challenges with this, and some people's eyes focus so quickly that it's not as easy to accomplish this task as I might have first thought.

Admittedly we are getting into the weeds here, but I thought it worth exploring further. My vision is not the best and I often do not feel my reticle is as sharp as it should be. There may be no method of scope adjustment that overcomes my astigmatism however, lol.

 

[nn8734]

I crank the scope to max power, focus on something large and far away, adjusting the diopter until its as clear as possible. I then glass objects from ~100 yards out to the max effective range of the system, adjusting the parallax as i go, confirming i can get both reticle and target in sharp focus at all relevant distances. If need be, I adjust the diopter.

not saying this is the “right” way to do it but has always worked for me.

 

[clcustom1911]

PSA on how to set up diopter.

I've used this on both SFP and FFP rifle optics and my FFP spotting scope reticle.

 

[Glassaholic]

There's more than just the reticle that the diopter has an effect on. Parallax is another function that is affected by the diopter. I use a hybrid method adopted from hk dave and ILya where I use the typical manufacture recommendation for adjusting the diopter for the reticle (but recently I've been trying the method ILya mentions in the video above) and then after that I do a fine tune adjustment for image clarity as well as parallax, here is my method:

Here is my recommendation, but I don’t take all the credit, much of this comes from advice provided by hk dave, ILya and my eye doctor:

• Initial setup: Loosen the lock ring in front of the eyepiece (if it has a lock ring) and while looking at a blank wall or the sky, rotate the eyepiece several turns counterclockwise (in the positive + direction) until the reticle is visibly out of focus. Then turn back clockwise until the reticle is focused as sharply as possible (but be careful not to go too far; however, when doing so be sure you are not staring through scope while turning back clockwise, you should glance through the scope for no more than a few seconds then stare out into the distance while making a small adjustment and then glance back – do this until the center and the edge of the reticle appear sharp.
• Fine tuning: Find a target that is very far away, so that it looks sharpest when the side focus is at the infinity setting. As you look through the scope (important that it remains steady) you can mess with the diopter by making minute adjustments either CW/CCW and see if the reticle and/or image improves any. You can also check parallax to ensure that small head movements don’t cause the POA to shift.
• Closeup tuning: Now find a target that is closeup, say 100 yards away, set your side focus until the object comes into best focus, does the reticle still look sharp? Check parallax to make sure there is no shift.

Once you’ve performed the above 3 steps you should be set with your scope, it might be wise to mark your ocular and the scope tube with a pen or marker (especially if you don’t have a locking diopter) so you can return to this position if your scope is ever bumped out of alignment.

I have actually found the manufacturer's method and the PSA on how to setup diopter thread here on the Hide to be insufficient for those of us who struggle with the reticle always looking in focus through a wide range of settings. My eye doctor says I have 20/15 vision so I'm not sure if that has an affect on how the reticle looks, but I've had to modify my diopter methodology in order to get a good sight picture and get parallax to settle down.

 

[A&8's]

Power setting is irrelevant, although I generally use higher powers.

Turn para to infinity...look thru scope at blank, light colored wall, ground, piece of paper, etc.....adjust eye piece....look away for a couple seconds....repeat as many times as needed until reticle is razor sharp the instant you look thru the scope. That's it.

 

[makaug]

OP, I'm sure Ilya will chime in, but I don't believe you've described his methodology. He focuses the reticle at the lowest magnification he can easily make out the fine lines of the reticle, then VERIFIES it at his most commonly used magnification settings. The reason being that the thicker the reticle is, the wider the diopter range the reticle will still appear focused (his video goes into the details why), and the harder it is to find the center of that range.

At least, that's how I understood his videos.

 

[Alabusa]

I set the mag to highest power and parallax to infinity.

 

[Glassaholic]

OP, I'm sure Ilya will chime in, but I don't believe you've described his methodology. He focuses the reticle at the lowest magnification he can easily make out the fine lines of the reticle, then VERIFIES it at his most commonly used magnification settings. The reason being that the thicker the reticle is, the wider the diopter range the reticle will still appear focused (his video goes into the details why), and the harder it is to find the center of that range.

At least, that's how I understood his videos.

I'm not the OP but I think you're referring to my post above, I mention that I use a "hybrid" methodology between mfr, hk dave and ILya's method, this is what I've found works best for my eyes, as using the mfr recommended method alone does not get me close to where the diopter needs to be for the utmost clarity (that a particular scope can provide) and a parallax free image. One of the most difficult scopes to set the diopter on was the Vortex PST II 5-25x50, initially I was a bit disappointed in IQ, but that is when I began to use hk dave's method and found that with fine tuning the scope performed much better. I often wonder how many shooters sell scopes because they are frustrated with the performance but in the end it might have been they just had not adjusted the diopter properly. Years ago this happened to me with the T5Xi, I was sorely disappointed with it's performance and sent it back to the dealer only to have him contact me and say "your diopter was way off", I was embarrassed but it was a good lesson that sometimes the issue is not with the equipment but the idiot behind the equipment

 

[makaug]

I'm not the OP but I think you're referring to my post above, I mention that I use a "hybrid" methodology between mfr, hk dave and ILya's method, this is what I've found works best for my eyes, as using the mfr recommended method alone does not get me close to where the diopter needs to be for the utmost clarity (that a particular scope can provide) and a parallax free image. One of the most difficult scopes to set the diopter on was the Vortex PST II 5-25x50, initially I was a bit disappointed in IQ, but that is when I began to use hk dave's method and found that with fine tuning the scope performed much better. I often wonder how many shooters sell scopes because they are frustrated with the performance but in the end it might have been they just had not adjusted the diopter properly. Years ago this happened to me with the T5Xi, I was sorely disappointed with it's performance and sent it back to the dealer only to have him contact me and say "your diopter was way off", I was embarrassed but it was a good lesson that sometimes the issue is not with the equipment but the idiot behind the equipment

Not only people selling scopes, but I wonder how much of the IQ feedback we read about on forums is affected by sub-optimal diopter settings. Thankfully grains of salt are easy to stock in quantity until you can get your own eyeball behind a piece of glass.

Here is the statement about the video made by the OP I was referring to in my previous post:

The gist of it, adjust the focus of the reticle at the magnification you most commonly intend to use the optic.

 

[koshkin]

OP, I'm sure Ilya will chime in, but I don't believe you've described his methodology. He focuses the reticle at the lowest magnification he can easily make out the fine lines of the reticle, then VERIFIES it at his most commonly used magnification settings. The reason being that the thicker the reticle is, the wider the diopter range the reticle will still appear focused (his video goes into the details why), and the harder it is to find the center of that range.

At least, that's how I understood his videos.

That's correct (for FFP scopes).

ILya