A lens has to be ground to a curve in order to get magnification. So once it is curved, the magnification power is determined by the distance away from the ocular lens (the one near the eye.)
But once you grind a lens to a convex curve, it is impossible for it to ever render a true 1X again, as it will always be magnifying slightly. And it would have to get very close to the ocular lens to get close to 1x.
"The frost on the ground probably envies the frost on the trees."
Posts: 8282 | Location: Marietta, GA | Registered: February 10, 2009
It all has to do with magnification range and marketing. People who buy low power scopes have their reasons for wanting a 1X or close to bottom magnification. Manufacturers try to show a great range in these scopes to make them more desirable.
If you start with a 1X scope and you have a 3X zoom, the standard range, your scope will be a 1-3X32, let's say. On the other hand, if you start with a 1.5X base, your scope can then be marketed as a 1.5-5X32. It's still a 3X zoom, and the top end is really not 5X, it's 4.5X but nobody will argue with you as it's really difficult to see the difference between 4.5X and 5X.
Now if your zoom ratio is 4X, you have a 1.5-6X32 and people think it's a 6X zoom, because no one cares about the difference between 1X and 1.5X.
If your zoom ratio is 5X, your 1.5X now becomes a 1.5-8X32. Wow, that's like an 8X zoom ratio.
See how that works?This message has been edited. Last edited by: NikonUser,
Posts: 2739 | Location: Texas | Registered: June 20, 2012
Man, I still don't get it. They could have said "1-5 Power" and it would have at least made sense. Seems like an idea somebody came up with to make it sound more precise. Seriously, it's like my eye doctor appt last week when the doctor said "what's clearer, number 1 or number 2?" and you don't really see a difference or cannot decide…
Like so many things, the devil is in the details. For the hunter shooting large game, there may be no apparent difference between 1× (really, truly no magnification of the sight image) and 1.5×. But if, for example, a sight is being used for something like clearing a building or other close distances with scanning, it matters a lot. Or at least it does to some of us. Other people claim that they can use 3 or even 4-power sights for such purposes without any distraction or handicap, but it took only a couple of experiences with a nominal 1.5-5× scope for me to ditch it in favor of one with no magnification.
As already mentioned, getting a true zero magnification setting in a variable magnification optical sight is/was evidently difficult because it took a long time for it to show up at all, and as far as I know, they’re still fairly expensive.
I have a Leupold Mark 6 1-6×20mm sight that has as close to zero magnification at the 1× setting as I can detect, and it cost far more than the rifle it’s mounted on. Plus it’s still an optical device with lenses to look through. That introduces a small amount of image distortion at the edges when scanning, but as I say, I can’t detect any magnification at the lowest setting.
“I can’t give you brains, but I can give you a diploma.” — The Wizard of Oz
Posts: 37876 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002
I have read many hunting stories by professional hunters that used scopes preferred 1.5 power because it offered the widest field of vision with some clarity for dangerous game that was in very close. In my world I often hunt in thick cover and like 1.5x because I can get on target quicker. With any thing higher power it can be impossible to find your target.
Posts: 1584 | Location: owosso,Mi. USA | Registered: August 18, 2002