Scope focus???!!!

[Farlsincharge]

Okay, I'm confused, here's the deal. Basically every scope I have is a higher power unit with side adjust parallax. I notice that the parallax adjustment affects the focus as well. I have been told that this is not right and focus should be set at the eyepiece.
Which brings me to my next confusing point. Every time I mount a new scope I fiddle with the eyepiece and it never seems to make a difference. The cross hairs always look good no matter where I set the eyepiece. When adjusting the eyepiece I am looking at the sky, but I am not sure where the parallax setting should be while doing this, or if it makes any difference.
I do notice sometimes while shooting that the crosshairs do seem to fade away. I always attributed it to the angle of the sun or a busy target area, is there something that may remedy this?

Please somebody tell me what is going on and what is the proper procedure for focusing a scope.

 

[Grizzlypeg]

The adjustment at the eyepiece for the reticle sharpness can be confusing. Its used to set the reticle into focus while looking at objects at a distance through the scope. So to set it correctly, you should aim the scope off at infinity, the sky, the clouds, look off at infinity and then look through the scope. Don't focus on the reticle, keep looking off at a distance. If the reticle focus is set right, the reticle will be immediately in focus. If you simply stare through the scope at the reticle, your eye will make its own adjustments and attemp to put the reticle into focus. This is wrong, and will make for eye strain.

The side parallax adjustment is to put the object at a distance into focus and minimize or eliminate parallax. Off the bench, play around with it by focusing it until the target is sharp, then moving your eye off centre off the scope. The crosshairs / reticle should not move in relation to the object when you move your eye, when it is set correctly for that target distance.

 

[Shooter ----/]

Yup. What Grizzlypeg said.

 

[Mystic Precision]

I think of it this way.

The eye/objective focus dials in the reticle AND has slight influence on the image focus.

The side focus is the image focus just like a SLR camera. When a scope is up properly, the image will come into focus and the reticle will be sharp.

Both images coincede on the same focal plane in your scope. Parallax is also eliminated concurrently.

Now, Sometimes when you dial a variable scope through its mag range and/or elevation adjustments, the objective focus can change slightly because of the movement in the internal lenses. The reticle is still in focus (really wide range of useable focus) but the image isn't quite as sharp as it was.

for some scopes, this is something that cannot be resolved except to return the lenses to a more central location in the tube.

for others, a slight adjustment of the objective can bring the clarity and resolution back inline.

I like to look at a street sign or license plate about 700 to 800yds away when setting up my scopes. It is very hard to read script that far away if the scope doesn't have great glass.

The more off center you sight in your scope ie full down for LR shooting, the more likely you will find you need a bit of tweaking to keep image quality at its best. Why, centering for windage mechanically is a great thing.

A number of high travel scopes simple will not keep the image in focus at extremes of travel.

The Sightron SIII's do a wonderful job of keeping the image crystal clear and sharp through most of its working range but at the extremes, you will need to tweak the focus knobs - but they will work.

Jerry

 

[PSE]

I have a Leupold 3X9 with adjustable objective on the objective lens not on the side. I've played around with it but cannot notice a difference in image focus. I usually end up putting it on the yardage hash mark that I'm shooting at. Not sure if this is exactly the right way to do it but like I say I can't notice a big difference in image quality.