Is parallax ajustment really important?

[hack3rpt]

So I bought a Leapers 3-9x40 (will arrive in 3 days) and it doesn't have AO. It has a fixed parallax at 35 yards, and for the most part, I plan to shoot at 30 meters so it's close enough, but if I want to shoot closer, let's say at 15 meters, at the minimum magnification, does parallax have a big effect? I think I can keep my eye centered to deal with the crosshair moving a bit, but will it be too much out of focus, or will it still have great quality?

Thanks in advance.

[Black Beard]

Should be fine at 15 yards. Check it before you attach it to the scope rings (which might mark it) just in case you are not happy. Don't forget to adjust the eye piece to focus the reticule before you check (granny, sucking eggs, I know).

[hack3rpt]

Should be fine at 15 yards. Check it before you attach it to the scope rings (which might mark it) just in case you are not happy. Don't forget to adjust the eye piece to focus the reticule before you check (granny, sucking eggs, I know).

Thanks for the help!

[BTDT]

Maximum POI shift in any direction

O x (P-R) / 2P

Where:

O = Objective lens radius

P = Parallax focus range

R = Target range

Therefore, a 40mm objective focused at 35 yards will give a maximum POI shift at 15 yards of

20 x (35-15) / 70

Or 5.71mm.

You'd only get that sort of shift if you deliberately tried to look through the scope as far from its axis as possible; in practice, shift will be nearer a quarter, or ~1.4mm.

No big deal.

[hack3rpt]

Maximum POI shift in any direction

O x (P-R) / 2P

Where:

O = Objective lens radius

P = Parallax focus range

R = Target range

Therefore, a 40mm objective focused at 35 yards will give a maximum POI shift at 15 yards of

20 x (35-15) / 70

Or 5.71mm.

You'd only get that sort of shift if you deliberately tried to look through the scope as far from its axis as possible; in practice, shift will be nearer a quarter, o1 ~1.4mm.

No big deal.

Thanks for the really elaborate answer! Might use this to calculate some other distances later.

[Portzy]

I have posted this a few times but you may find it useful.

https://www.lelandwest.com/parallax-...6272596b1b5e1f

[flintlock50]

Maximum POI shift in any direction

O x (P-R) / 2P

Where:

O = Objective lens radius

P = Parallax focus range

R = Target range

Therefore, a 40mm objective focused at 35 yards will give a maximum POI shift at 15 yards of

20 x (35-15) / 70

Or 5.71mm.

You'd only get that sort of shift if you deliberately tried to look through the scope as far from its axis as possible; in practice, shift will be nearer a quarter, or ~1.4mm.

No big deal.

Thanks for that Jim.