It's possible already in ARMA 3... just go into a land vehicle with mounted weapons you'd find the zoom is gradual, so it's an existing feature... I do agree, very little scopes actually "clicks" between magnification, the only one that I know of is the Elcan spectre, but others are usually dials that does it gradually.

The stepped zoom results from the sight having two different opticsview models that allow the mildot reticle to be correctly scaled against targets at both zoom levels (each dot is one mil apart, i.e they measure a length of 1 meter at a distance of 1000 meters). One model has the mil-dots scaled correctly for opticsZoom = 0.04 (nominally 10x zoom) and the other model has the mil-dots scaled for opticsZoom = 0.01 (nominally 85x zoom).

Allowing the mil-dots to scale with zoom is an important feature for range estimation:

http://www.mil-dot.com/articles/how-to-get-the-most-out-of-your-mil-dot-reticle

This is why most real-world sniper optics have the reticle in the First Focal Plane.

Currently it's not possible to scale reticles based on sight zoom levels using the continuous zoom feature of Arma 3, as continuous zoom only uses one opticsview model. This means the mil-dots would only work for one exact zoom value.

The continuous zoom feature can only be used on sights that are intended to represent scopes with the reticle in the Second Focal Plane.

BIS could try and approximate a more smooth transition between the minimum and maximum zoom levels by having more 'steps' in the modelOptics array, which requires making more models for the optics view with appropriately scaled reticle textures for each model.

For example I have made a scope addon for Arma 3 that has 5 discrete zoom levels (5x, 10x, 15x, 20x and 25x) using 5 separate optics view models with the reticle scaled correctly in each model. I can assure you it's quite a lot of work to make lots of different models for each zoom level :D

da12thMonkey: ACE 2 had a front focal plane sight on one of the sniper rifles with variable (gradual) zoom. It was buggy, but it worked. http://wiki.ace-mod.net/sys_reticles

What I meant was you can't do it with the current implementation BIS are using for sight models, in the context of this being ticketed as a bug.

The ACE system was a separate FSM-based scripted solution to provide an overlay on top of the weapon optics IIRC. It didn't use any of default core modeloptics mechanics other than the FOV settings. Adding something like that would need ticketing as a feature request, not a bug-fix.

There is already a ticket to add it as a feature:

http://feedback.arma3.com/view.php?id=8446

Not entirely sure how well the old ACE method would work now either, since the sights are now being modelled without the black shroud around the edges which occluded the parts of the reticle that were scaling outside the field-of-view through the scope.

Thanks da12thMonkey, that's perfect explanationof this. This is not a bug, it's our feature. We have functional mildot system with two zoom values for this sight. We can try look at it after our priorities gone and maybe findout some solution to make it better. Now it's duplicated feature request. Thanks a lot for feedback... You can watch this there 0008446