@steve123 Don’t take any of this personally. I appreciate your calm tone.
TL;DR
On a 1-10x or similar the zoom ring
acts like a focusing apparatus because target type/size/distance usually corresponds to a magnification which has an appropriate apparent DOF for the task.
In other words, “appears in focus” is good enough for what these scopes are designed for.
I know that “focus” and “parallax” are not quite the same thing.
@koshkin, I believe, mentions that the parallax knob is more accurately called a focus knob. See this video of his:
Know that in this post when I say parallax or focus, I mean the same thing: the image appears in focus to your eye…even though technically they are not the same thing.
Back to your scenarios: It does seem like you are moving the goalposts quite a bit here.
For me it's as much as having a perfectly focused image as having the parallax dialed out.
This is sorta what I’m getting at when I give people crap about
acting (vs. being) autistic about this stuff. Yeah, I like a perfectly focused image too.
But we’re talking about snapshot hunting and DMR roles here (people shooting back). Not sniper stuff.
Concerning the adjustable parallax one specific application I am thinking of personally is using that Athlon for Pistol Field Target matches on 12x. We use the focus to determine distance so if one doesn't know the distance, well, you won't do well in this sport.
See hunting/DMR roles. Of course I’m not saying a 1-10x or 2-10x scope should never be designed for the likes of you, just that for Pistol Field Target…well, if that isn’t a super-super niche then I don’t know what is?
Then in an Ultimate FT rifle match which is out to 100Y with air rifles on kill zones which are a bit difficult in size. I got a 2nd place using this same scope.
Again, super-super niche. Not hunting/DMR.
And there are the rimfire applications for a crossover scope. I can imagine walking through the junipers and shooting a rabbit while it’s running away on 2x, or crossing over to shooting long range jacks or prairie dogs at whatever distance.
You’re not adjusting parallax after you see a rabbit, right? You’ve pre-set it, and guess what? It’s almost certainly going to be off. Odds are the rabbit will not appear exactly where are you preset your focus.
With a non-adjustable parallax scope, you just pre-set the zoom at 1x or 2x.
The zoom functionally acts like your parallax/focus!
In other words, because it’s on such a low mag
everything is going to appear in focus already. Wide angle lenses (ex. 1x) have greater
apparent DOF, even though, just like a 600mm telephoto, technically only one distance is actually in perfect focus.
You just won’t be able to visually determine that perfect focal point when looking at photo taken with a wide angle lens or while looking through a riflescope at 1x mag*. Or you’ll have great, great difficulty figuring out that exact plane of perfect focus and would need to take significant time to study the image carefully in order to do so.
Meanwhile the rabbit has escaped!
To be crystal clear, I am
not saying the zoom is mechanically identical to your parallax/focus knob, only that the practical result in the rabbit situation is the same.
And if you want to take a longer shot, the parallax is fixed on 150yds. But stuff past 150yds is going to look in focus and the parallax error will not be enough to matter for the situations the scope was designed for (shooting coyotes or larger…or people…out to what? 400, 600, 800 yds?).
For stuff up close the lower zoom settings sort of forgive less-than “perfect” parallax/focus settings.
You get what I’m saying?
Or general hunting for a centerfire. Good up close and okay far away.
See the “using the zoom to negate out of focus game” when it is close to you. You’re not shooting a deer at 25yds at 10x, you’re going to be at 1x or 2x, and at that range the deer is going to look in focus.
For example, at 1x with my Razor 1-10x stuff in my house at 3/4yds looks like it’s in focus. Heck, even closer. That’s what I’m trying to get at here.
A 1-10x or 2-10x in general is about speed-to-target. Zoom functionally works like your focus and that corresponds to how far your target is away from you.
Target is close? Zoom out and it looks like it’s in focus.
Target is far? It’s going to look like it’s in focus at any zoom setting.
It’s the difference between knowing that, technically, only one distance can be in perfect focus at any one time but that, depending on zoom setting, there can be a very wide range of acceptable focus that
gets the job done.
In short, the fixed parallax 1-10x/2-10x scope is telling you to…
And I think this is what drives some people wild.
Of course I’m not saying you don’t get to have preferences and that some options on some scopes aren’t super helpful to you in your competitions. It’s just these situations are extremely niche.
I’m just describing, broadly, what this sort of scope is typically used
and designed for.
If you have an edge case, just state that preference (like you did) and hope that a manufacturer is listening or write to them. Looks like you luckily found the perfect scope for your application.
Some people (not you) just spazzzzz out and are offended by the
mere idea that a scope has a fixed parallax. They throw out a bunch of hypotheticals that don’t hold water. Then they go
Reeeeee!
Those people are acting autistic.
The same people also usually want an extremely light scope…but adding adjustable parallax adds weight
Reeeeee!
*I’m ignoring f-stop. Hopefully you get the drift.