Parallax Adjustment

[JRS]

This is really simple because you can see parallax for yourself. If you want to know if your scope requires a parallax adjustment when an elevation adjustment is made, do a test. Adjust the scope so that it has no parallax, put in any amount of elevation that you think suitable, and then check to see if you have parallax. It could not be simpler. The only tool that you need is your shooting eye.

You can't completely remove parallax, not matter what you do!

 

[BoydAllen]

Perhaps you can't, but I can. How do you adjust your scope....the whole thing from start to finish?

 

[JRS]

Perhaps you can't, but I can. How do you adjust your scope....the whole thing from start to finish?

Evidently, you know something the optical engineers and experts don't! Sharing that expertise and knowledge could prove to be quite financially rewarding, for you!

 

[XBBR Shooter]

You can't completely remove parallax, not matter what you do!

Evidently, you know something the optical engineers and experts don't! Sharing that expertise and knowledge could prove to be quite financially rewarding, for you!

You must be doing something wrong - engineers solved it in the beginning of optics.

When the image ;lane is in the same place as the reticle plane, there is no parallax. If you don't understand that, then you do not know, or understand parallax.

 

[Ggmac]

And remember , the # for range , printed on the scope , ARE FOR REFRENCE ONLY .

 

[M-61]

And remember , the # for range , printed on the scope , ARE FOR REFRENCE ONLY .

Yes. In fact the numbers (range) can tend to be misleading. If you are at 100 yards and parallax is dialed out yet the corresponding number says 70 you assume something must not be correct. It is not a range finder.

 

[majohnson]

The brown truck drop off a new scope week. Once it was zero, I went though a 20 moa up box text and never had to reset the parallax or on it. No matter how I dialed evelation or windage, all the bullets line up. It still odd, pointing at at one spot and having the bullet hit a completely different area.

I am glad my scope company does not put distances on the knob. Thanks everyone for all the imput.

 

[BoydAllen]

Evidently, you know something the optical engineers and experts don't! Sharing that expertise and knowledge could prove to be quite financially rewarding, for you!

No, it has not, because I have explained how it is done to a number of shooters who actually wanted to solve their problem, for free, just to be helpful.There is one particular post that gets linked to a lot, in discussions of parallax, that may be leading shooters astray. It is mostly correct, but leaves out one important direction, and makes a flat statement that is incorrect. Many who look to the internet for their answers seem not to be inclined to experiment, even when doing so would not damage anything. As far as optical engineers go, I will leave that discussion to others. What I can tell you is that by my own experimentation, I learned to take all of the parallax from my adjustable scopes, and have peak target sharpness at the same time....and I have shown and told others how to do the same thing. It is not difficult. All you have to do is listen (or read) and follow directions.

 

[Mr.Knowit all]

I read that the clearest picture is when your scope is at zero. No cant- just in the middle. Not sure if that helps you out.

Boyd helped me out on the subject of parallax last month. You may want to pm him.

 

[Turbulent Turtle]

I read that the clearest picture is when your scope is at zero. No cant- just in the middle. Not sure if that helps you out.

Boyd helped me out on the subject of parallax last month. You may want to pm him.

Yeah, that's called the sweet spot. The lens is ground best at the middle and does not produce any optical effects like barreling or other distortion as compared with viewing off center. The further away you are from the center of the lens the more distortions are possible.

 

[P72]

My thoughts are that scope optimum performance is obtained when the reticle is centered or close to being centered.

The focal plane of the image formed by the objective len(s) should coincide with the reticle upon making a parallax adjustment using an adjustable objective, side focus, or ocular focus (eye piece), if not a fuzzy image and target movement will be noticed upon moving your eye - mostly with scopes having more than 10X magnification. Should, for some reason moving the erector tube with enclosed reticle cause the reticle to be moved away from the image focal plane parallax might be noticed. I have not seen this but it seems sort of possible.

 

[Turbulent Turtle]

My thoughts are that scope optimum performance is obtained when the reticle is centered or close to being centered.

The focal plane of the image formed by the objective len(s) should coincide with the reticle upon making a parallax adjustment using an adjustable objective, side focus, or ocular focus (eye piece), if not a fuzzy image and target movement will be noticed upon moving your eye - mostly with scopes having more than 10X magnification. Should, for some reason moving the erector tube with enclosed reticle cause the reticle to be moved away from the image focal plane parallax might be noticed. I have not seen this but it seems sort of possible.

Let me just say that you do NOT adjust parallax with the eyepiece focus. That should be set while taking quick peeks at clouds or a blank wall until the reticle appears sharp and crisp and it should be locked down at that point only to be changed if your eye changes.

You adjust for parallax ONLY with the AO or the side focus. If you're also twiddling the eyepiece focus, you are hopelessly lost and need to read the preceding paragraph again.

 

[XBBR Shooter]

My thoughts are that scope optimum performance is obtained when the reticle is centered or close to being centered.

This is a very popular, but untrue myth. The reticle is ALWAYS centered - it is mounted in a metal ring and fixed in place - it does NOT move.

The focal plane of the image formed by the objective len(s) should coincide with the reticle upon making a parallax adjustment using an adjustable objective, side focus, or ocular focus (eye piece)...

You CANNOT make any parallax adjustment with the eyepiece. The eye piece should be adjusted when you first mount the scope, and then left alone.

Should, for some reason moving the erector tube with enclosed reticle cause the reticle to be moved away from the image focal plane parallax might be noticed. I have not seen this but it seems sort of possible.

This is impossible because the reticle is NOT... NEVER EVER, mounted in the erector cell. The erector cell is mounted at a stage before the reticle plane, normally, right in front of the reticle plane.

http://www.snipercountry.com/Articles/Parallax.asp

.

 

[P72]

Check out the SWFA Super Sniper scopes that have a rear mounted parallax adjustment - go on line and see the SWFA site.

Next read:www.accurateshooter.com/optics/parallax-in-rifle-scope/ from U.S Optics

The statement is made that to the effect that if the reticle moves even a small amount parallax will occur. The reticle is intended to be fixed and not move.

Then look at the link where parallax adjustment methods are discussed - yes - there is such a thing as a rear mounted ocular parallax adjust. Referred to as "2nd focal plane adjustment" not the reticle focus. The ocular term meaning the back of the scope where your eye is as opposed to the front or objective end.

The reticle might not move but the elevation and windage adjustments push against the erector tube that contains the reticle moving the tube and associated lenses suspended by spring compression.

 

[XBBR Shooter]

Check out the SWFA Super Sniper scopes that have a rear mounted parallax adjustment - go on line and see the SWFA site.

Next read:www.accurateshooter.com/optics/parallax-in-rifle-scope/

Then look at the link where parallax adjustment methods are discussed - yes - there is such a thing as a rear mounted near ocular parallax adjust. Referred to as "2nd focal plane adjustment"

The reticle might not move but the elevation and windage adjustments push against the tube that contains the reticle moving the tube and associated lenses suspended by spring compression.

Sorry, but you are wrong.

This is NOT the eyepiece adjusting parallax.
That ring is in FRONT of the eyepiece and has nothing to do with focusing the eyepiece...
i own one of those scopes (the B&L 10x Tac).

You are misunderstanding the terms being used.

The elevation adjustments do NOT push against the tube holding the reticle - the reticle is NOT mounted in a tube. It is mounted in the body of the scope. Nothing is connected to the reticle mount, and the mount does NOT move the reticle - the reticle never moves.

Elevation and windage is done by either moving (tipping) one end of the erector cell, or moving an intermediate field lens to sweep the prime image across the reticle plane.

You do not understand optics, or how these things work.

I was a consultant to Premier Reticles, when the father (Dick Thomas) ran the company. I did patent work for them (against US Optics).

The diagrams on the US Optics link are kindergarten grade stuff.

 

[BoydAllen]

The whole focus the eyepiece, lock it down and never touch it thing is in error for the following reason. Even if the shooter follows the correct procedure, the eyepiece may be focused ever so slightly out of the plane of the reticle. I have helped numerous shooters at the range with a specific problem that this approach does not address or solve, that is when the target is at its sharpest, there is still some small amount of parallax, perhaps as little as the width of the cross hair, or only slightly more. The other way of saying this is that when parallax has been adjusted so that it is completely gone the target is not at peak sharpness. Personally, I do not care to argue about scope theory, because I have a technique that I can use to solve the problem. It involves making very small adjustments of the eyepiece while at the range and with a target down range. A small move is made at the eyepiece, the target image refocused to peak sharpness, and the setup tested for parallax. If it is worse, the adjustment was made in the wrong direction, and after putting things back as they were, a very small move should be made in the other direction, the target image refocused, and parallax checked. Eventually you should arrive at an eyepiece adjustment that has the target at its sharpest and no parallax. For those that insist that eyepieces have nothing to do with parallax, if your scope is in perfect adjustment so that there is absolutely no parallax, and your target image is as sharp as your scope's' optics are capable of, move your eyepiece adjustment just a little, but not so much that the cross hairs are not sharp and black, and the test for parallax. The change that you made will refocus the eyepiece slightly out of the plane of the reticle, and there will be a small amount of parallax. All of this presupposes a second focal plane reticle. I have no experience with FFP scopes. Summing up, someone can be 99% right and only 1% wrong, but when the 1% is about the problem under discussion, it can lead people seriously astray. The funny thing is that these days people seem to be overly concerned with following advice that comes to them via the internet, from people that they do not know, and they seem to be afraid to use their own intellect and do some experimenting, even when no harm could result. I realize that my advice is just more from someone that you do not know, on the internet, and the only qualification that I have is that others have followed the directions that I have provided and solved their problem. Don't take my word for this, try it. If you do it correctly, I think that your results will speak for themselves. Good luck and good shooting.
Boyd Allen (not a screen name)

 

[P72]

What did I say -- "near ocular parallax adjust " would not that parallax adjust ring be near the ocular end of the scope? "not the reticle focus" or "second focal plane adjust"

the attached link shows the inner working of a scope that would probably be the same as most scopes - a second focal plane scope with reticle

and should the reticle move - a defect, parallax would occur since the focal plane not coincide with the reticle

the referenced diagram might be sort of simplistic but it shows the fundamental principles

got to admit that reticle sort of looks like it is fixed to the scope not the erector tube but give me credit for "the reticle might not move"

www.gameandfishmag.com/gear-accessories/look-inside-riflescope/

 

[XBBR Shooter]

What did I say -- "near ocular parallax adjust " would not that parallax adjust ring be near the ocular end of the scope? "not the reticle focus" or "second focal plane adjust"

the attached link shows the inner working of a scope that would probably be the same as most scopes - a second focal plane scope with reticle

and should the reticle move - a defect, parallax would occur since the focal plane not coincide with the reticle

the referenced diagram might be sort of simplistic but it shows the fundamental principles

got to admit that reticle sort of looks like it is fixed to the scope not the erector tube but give me credit for "the reticle might not move"

www.gameandfishmag.com/gear-accessories/look-inside-riflescope/

Nope - no credit - bad article.

 

[Nude nut]

The whole focus the eyepiece, lock it down and never touch it thing is in error for the following reason. Even if the shooter follows the correct procedure, the eyepiece may be focused ever so slightly out of the plane of the reticle. I have helped numerous shooters at the range with a specific problem that this approach does not address or solve, that is when the target is at its sharpest, there is still some small amount of parallax, perhaps as little as the width of the cross hair, or only slightly more. The other way of saying this is that when parallax has been adjusted so that it is completely gone the target is not at peak sharpness. Personally, I do not care to argue about scope theory, because I have a technique that I can use to solve the problem. It involves making very small adjustments of the eyepiece while at the range and with a target down range. A small move is made at the eyepiece, the target image refocused to peak sharpness, and the setup tested for parallax. If it is worse, the adjustment was made in the wrong direction, and after putting things back as they were, a very small move should be made in the other direction, the target image refocused, and parallax checked. Eventually you should arrive at an eyepiece adjustment that has the target at its sharpest and no parallax. For those that insist that eyepieces have nothing to do with parallax, if your scope is in perfect adjustment so that there is absolutely no parallax, and your target image is as sharp as your scope's' optics are capable of, move your eyepiece adjustment just a little, but not so much that the cross hairs are not sharp and black, and the test for parallax. The change that you made will refocus the eyepiece slightly out of the plane of the reticle, and there will be a small amount of parallax. All of this presupposes a second focal plane reticle. I have no experience with FFP scopes. Summing up, someone can be 99% right and only 1% wrong, but when the 1% is about the problem under discussion, it can lead people seriously astray. The funny thing is that these days people seem to be overly concerned with following advice that comes to them via the internet, from people that they do not know, and they seem to be afraid to use their own intellect and do some experimenting, even when no harm could result. I realize that my advice is just more from someone that you do not know, on the internet, and the only qualification that I have is that others have followed the directions that I have provided and solved their problem. Don't take my word for this, try it. If you do it correctly, I think that your results will speak for themselves. Good luck and good shooting.
Boyd Allen (not a screen name)

Boyd,
Will this method help with horizontal parallax my vertical is fine just cant get rid of horizontal its only slight but it there.

Cheers Trev.

 

[XBBR Shooter]

Boyd,
Will this method help with horizontal parallax my vertical is fine just cant get rid of horizontal its only slight but it there.

Cheers Trev.

That comes from astigmatism... it is in your eyes, or a problem with your glasses.