Is glass quality in scopes actually a factor?

[PathFinder]

On the extreme end it can be a deal breaker. I've had several experiences with a SWFA 12x where an animal could not be discerned from its surroundings with the scope when it was plainly obvious in good binoculars of the same magnification. Those were all deer in thick brush/trees/quakies where they were difficult to see even in top shelf glass (Swaro NL & STS 65), but in those conditions the glass quality of the rifle scope made it nearly impossible or completely impossible to shoot because the target could not be identified.
In similar/identical conditions with the SWFA 3-9 and 5-20, that hasn't been an issue. The 5-20 glass isn't amazing, but is adequate for identifying a deer even in really tough visual conditions.
Zero retention is still a higher priority though.

 

[RockAndSage]

Other than what's already been said, for big game, the only thing I can add is that in some extremely high-contrast situations, while looking into very deep, dark shadow, good scope glass can matter. Think, noon-day September Nevada sunlight, looking deep into brush. That's a situation where the glass in observation optics absolutely does matter, regularly, in finding mule deer in those conditions - but not enough to matter in a rifle scope to make any tradeoff with things like durability, reliability, reticle, etc. Wait long enough, that buck will move enough to be shootable.

 

[streamerfish]

For me its pretty much, is it good enough, ok then moving on.

I'm more worried about eye box/eye relief, reticle, and how functional the turrets, turning the magnification dial etc is.

IDK, I guess I'm just not a glass geek. Obviously I will take better glass everything else being relatively equal, but not high on priority list. But I'm not shooting at animals past a few hundred yards (until my skills improve), and i have never had a situation where glass cost me a shot at game at first/last light.

 

[180ls1]

Hard to say. I almost lost a great buck in part to a "poor" glass quality scope. I have had other scenarios where I may not have harvested if I had lesser glass but we are talking 2, maybe 3 in 25 years of hunting.

At the fringes it can make a difference but those are rare. They may also be the scarce opportunities at the giants who are smart and nocturnal where every second counts.

 

[Wrench]

What kind of surgery did you have? My astigmatism is a real problem and I’d love to get that corrected.

I had lasik. I hear they've come a long way since.

 

[nm.otter]

in some extremely high-contrast situations, while looking into very deep, dark shadow, good scope glass can matter. Think, noon-day September Nevada sunlight, looking deep into brush.

Right.

Also low angle, near-axis light (sun going/coming over a ridge/hill, target just below that same hill).

 

[North of 60]

I had lasik. I hear they've come a long way since.

LASIK is some of the best money i ever spent.

Another thing i'd toss in here is have a large enough objective for deep dark woods/timber if you hunt in that vegetation in low light.