Focus and/or parallax

[Jarhead]

Hi All!

I am hoping again to tap into the 1000's of years of experience & distributed wisdom on this forum.

I am doing pretty well at tightening the groups on my Tikka T3.

I did notice yesterday at Hilltop a small problem that needs solving. I was shooting at 100 meters, so I preset the side mount parallax (Athlon ARES 6-24 x 50 BTR mil) to about 110 yards. 109 yards= 100 meters. The target was in focus and the reticle was no giving me an eyestrain headache so no problems there. However, bobbing my head over the stock showed that parallax was not aligned. I adjusted the parallax until the reticle and target were rock solid. The target was then out of focus. I was closer to 140yards on the parallax dial.

Is this a problem with the scope, my 49 year old eyes, my contacts, or something else altogether? I am near sighted requiring glasses or contacts to see far, and in the past 4 years, if I am wearing contacts, I need reading glasses to see close. Sigh……

[marksman]

is your ocular adjusted properly?

Turn your parallax to infinity and your zoom to max. Look at the sky and adjust your ocular until the reticle is crisp.

dont look at numbers

let us know how you get on

[No1_49er]

is your ocular adjusted properly?

Turn your parallax to infinity and your zoom to max. Look at the sky and adjust your ocular until the reticle is crisp.

dont look at numbers

let us know how you get on

Marksman, I believe you are almost correct with that description.
It is important when looking through the scope at the sky (but not necessarily the sky, cloud is also OK, so long as your eye does not have a background to focus on) that it is not much more than a passing glance. If you linger too long when looking into the blank background the brain automatically ensures that the eye adjusts its focus to see something sharp, i.e. the reticle. The process requires that you glance through the scope repetitively, and on each occasion adjust the ocular, a little at a time, until the reticle appears to be sharp against the blank background. It may require a "brutal" adjustment of, say, 1 or 2 turns in either direction to determine whether or not you are going in the right direction. It's a matter of fine-tuning from there.

[Larry]

Dont worry what markings are on the dial, some scopes are spot o with this others are way out. You did exactly the right thing moving your head slightly up and down and adjusting the parallax to stop any apparent movement on the target. yes it can sometimes be out of focus this you have to live with. It will give you the best results on the target.
As for adjusting the ocular think of it as different strengths of reading glasses. Its adjustment is purely for making the reticle easy to see. it is much more apparent if you do need reading glasses like 2* or 3* if you wind it all the way in the reticle will appear to fine to read. As you wind it out it is like increasing the strength of you reading glasses and become clear to read.

As No1 said dont look down the scope for too long as your eyes / brain will try to make adjustments. When you dont wear your reading glasses the muscles in your eyes try as hard as they can to adjust your lense in your eye. This will give you a head ache if it can make the adjustment as your eyes get worse the muscles can no longer adjust the lense and you cant read the text without glasses. The ocular adjustment is the replacement of reading glasses.

[Jarhead]

Thanks All,

I adjusted the ocular- I think you nailed it marksman! I did this aiming at a well lit piece of paper (not at the sky, I have great neighbours mostly, except for one who can not be described as being "cool with it"). I had to move it about 1/2 a turn. Now the parallax seems to be lined up with good focus, and the distance on the parallax has changed to 100 yards. I am doing this aiming at my favourite 100 M tree stump (everybody needs one of these!) , which I can just see from the back corner of my darkened garage so as to not freak out Mr. Not Cool With It. I will try again at Hilltop and see if I get the similar result there.