3. Parallax increases with short distances and high magnification ??

Parallax increases with short distances and high magnification ??

  • K

    The last paragraph of the parallax section of the wikipedia article on rifle scopes ... reads ...

    [quote] ... The reason why telescopic sights intended for short range use are often equipped with parallax compensation is that at short range (and at high magnification) parallax errors become proportionally more noticeable. A typical telescopic sight objective lens has a focal length of 100 millimetres (3.9 in). An optically ideal 10× scope in this example has been perfectly parallax corrected at 1,000 metres (1,094 yd) and functions flawlessly at that distance. If the same scope is used at 100 metres (109 yd) the target picture would be projected (1000 m / 100 m) / 100 mm = 0.1 mm behind the reticle plane. At 10× magnification the error would be 10 × 0.1 mm = 1 mm at the ocular. If the same telescopic sight was used at 10 metres (11 yd) the target picture would be (1000 m / 10 m) / 100 mm = 1 mm projected behind the reticle plane. When 10× magnified the error would be 10 × 1 mm = 10 mm at the ocular ... [/quote]

    I had not heard that before !!!

    Any thoughts ?? Is this valid ??

    ==
    In looking at the rest of the whole article I find some things that seem valid ... but others .. like the section on SFP versus FFP saying

    [quote] ... the majority of modern variable-power scopes are SFP ... [/quote]

    Restated, some of the info in the article seems relatively current ... other parts of the article seem like they were written 10+ years ago ...

    Just not sure about the parallax section, hence asking here in the "answer shop" !! :)

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  • While I'm not going to check the math... what they are saying rings true absolutely.

    Anyone that's tried smallbore benchrest at 50yds knows that is true. High magnification carries with it significant parallax penalties. High end scopes manage it well, while cheaper scopes tend to not.

    If you are at 25x magnification and parallax free at 50yds and try engaging targets at 30yds... you will see MASSIVE parallax error. I'm talking about as much as 3/4" or more of linear reticle movement error. Severe, by any measure.

    The part about majority of scopes being SFP is also correct. It's stupid, but it's a fact. Most optics are still SFP. Fudd's don't care, because they don't know. They don't know, and they'll argue against FFP and call it stupid and the people that choose it stupid. Only the popularity of field precision matches has made people aware of FFP. Heck, even I didn't run FFP until about 2006 or somewhere in there. People still argue with me when I suggest FFP. If you searched, you'd likely find dozens of threads where dumbasses were arguing against me when I suggested FFP. I finally just gave up. It's like arguing with a flat-earther.

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  • F

    @orkan said in Parallax increases with short distances and high magnification ??:

    While I'm not going to check the math... what they are saying rings true absolutely.

    Anyone that's tried smallbore benchrest at 50yds knows that is true. High magnification carries with it significant parallax penalties. High end scopes manage it well, while cheaper scopes tend to not.

    If you are at 25x magnification and parallax free at 50yds and try engaging targets at 30yds... you will see MASSIVE parallax error. I'm talking about as much as 3/4" or more of linear reticle movement error. Severe, by any measure.

    The part about majority of scopes being SFP is also correct. It's stupid, but it's a fact. Most optics are still SFP. Fudd's don't care, because they don't know. They don't know, and they'll argue against FFP and call it stupid and the people that choose it stupid. Only the popularity of field precision matches has made people aware of FFP. Heck, even I didn't run FFP until about 2006 or somewhere in there. People still argue with me when I suggest FFP. If you searched, you'd likely find dozens of threads where dumbasses were arguing against me when I suggested FFP. I finally just gave up. It's like arguing with a flat-earther.

    I have never seen a dumbass argue with you. Not once. Ever.

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  • K

    [quote] ... I have never seen a dumbass argue with you. Not once. Ever ... [/quote]

    haha ... you must mean you haven't seen it IN PERSON .. i.e. in the flesh ... well I haven't seen that either ... but I have certainly seen it 100 times on forums ... hecque, I've even been one of the dumbasses myself ... I think it was 2014 when I bought my L&S mk6-18x scope ... I was touting the advantages of SFP. Not really saying SFP was better ... but Greg was definitely pushing FFP. But to an observer, I'm sure part of the back and forth would've qualified as an "argument" if only from the logical perspective ... as in a "debate" ...
    I did buy an FFP .. and I've never bought a scope since that was SFP with a magnification of over 6x ...
    But back on the olde SC site at least a few years ago when most of us were still there ... I doubt a month went by when there wasn't an SFP versus FFP thread ... hecque we just had another one on Hide in the last few days. I'm just tired of pitching in myself ... after 100 times there is no point. The universe can make hard heads faster than we can educate them :)

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