Maven S.3A Spotting Scope

Back in 2013, Brendon Weaver, Mike Lilygren, and Cade Maestas founded a new optics company in Wyoming.  The goal was to provide optics that didn’t compromise on quality but cut out the middleman with a direct-to-consumer business model.  They further differentiated themselves by allowing the consumer to customize their optic to suit their preference.

Since then, they have steadily increased their catalog with high-value performance optics, specifically designed for hunters.

Maven S.3A Spotting Scope

The new Maven S.3A spotting scope expands that catalog in a few notable ways.  In order to see just how many ways, I took it out into the mountains of Montana deer and elk hunting in 2023. See it here.


A New Mid-Size Maven

Maven identifies their premium line of spotting scopes with the “S” designation.  The S.3 series is the newest scope after the full size S.1 85mm scopes and the ultracompact 56mm S.2 scope. The S.3 meets in the middle with a 67mm objective.  It is marked “Made in Japan.” The S.3 shares a lot of design cues with the S.1, but also has a few notable differences.

Removable Eyepiece

Besides the obvious objective size difference, the S.3 also is the first spotting scope from Maven with a removable eyepiece.  The included 20-40 wide angle zoom eyepiece features bayonet-style attachment, but isn’t secured by the usual push-button release of many of its competitors.  Rather, the bayonet mount locks with a rotating ring marked by “locked” and “unlocked” picture icons. The new features don’t end there however, as the tripod foot comes cut with an Arca-Swiss compatible dovetail already cut in the rotating collar.

Build Quality

Given the wide array of customizing choices provided by Maven like camouflage rubber armoring and custom color highlights, Maven still maintains a consistent build quality and feel among their optics.

Made In Japan

The S.3 is right in line here, with quality textured rubber armoring, machined aluminum focus wheel, and quality anodization throughout.  Everything feels dense and sturdy while adjustments are smooth and damped.

Flourite Containing Glass

Maven includes fluorite-containing glass in the design to help control color fringing from chromatic aberration.  Quality AR coatings and interior blackening prevent light loss while a quality hydro/oleo phobic coating on exterior lenses shed water and aid in cleaning.

Flourite Containing Glass

Other goodies include a rotating collar with eight detents every 45 degrees, and an extending integral sunshade with aiming device.

While the build quality is excellent, this does come with a weight penalty.  The Maven S.3A is rather short and compact at just under 12 inches long, but tips the scale at a plump 3 pounds 11.2 ounces. That is about 1/4 pound heavier than the Kowa 66A.

Optical Performance

The S.3A looks and feels the part, but how does it really perform?  To check it out, I put it up against the best 65mm spotter available:  the Kowa Prominar 66A.

I understand this isn’t a real “apples to apples” comparison. With a retail price of $1800, the Maven S.3A is a full $1100 less expensive than the Prominar’s $2900 retail price.  That is significant savings, but with my prior experience of Maven products outperforming their price point, I was anxious to see how big the performance gap between the scopes really was.

Maven S.3A

Resolution Testing

Following the norm in my spotting scope reviews, the first thing I did was evaluate close distance resolution of the optic.  With both spotters set to 40x (the max magnification of the Maven), both spotters resolved the same element on my Air Force 1954 Resolution chart at 35 yards.  Notably, the Kowa seemed to have a little more contrast, however.  I was able to resolve two smaller elements on the chart with the Kowa turned all the way up to 60x.  There is a real advantage to having the higher magnification available.

At long distance I set up an 8X11 eye chart at 530 yards.  Under overcast conditions with very little mirage, I was again able to resolve the same line of letters on the chart with both spotters at 40x.  This time though, the Kowa did show that line with a little more ease, likely due to the increased contrast.  Once again, the ability of the Kowa to go to 60x provided two additional resolved lines on the chart.

Low light testing once again showed the Kowa with a small edge on brightness at similar magnifications, but the Maven did well in this testing, hanging within a few minutes of the Kowa.  The Maven’s ability to go all the way down to 20x was a benefit in low light, as the additional exit pupil stretched low light performance into the darkest minutes of twilight.


The Maven is well corrected for distortion.  Only a small amount of “mustache” distortion is visible at the lowest power when tested against my garage door rectangles.  Turning the eyepiece up to the max 40x increases the visible distortion slightly, but again it is really mild.

Distortion at 20x

Distortion at 40x
The 20-40 wide angle zoom eyepiece is well corrected for distortion with just a small amount of mustache-shaped pincushion distortion.
Chromatic Aberration

The Maven S.3A is well corrected for chromatic aberration, where color fringing on high-contrast targets is invisible in the center of the field and only grows to a small amount near the edge.  This performance puts it near the top of options in the Maven S.3 price range.  Still, the near-perfect CA control of the Kowa Prominar is just a small bit better when it comes to the edge of the field.


The 20-40 zoom eyepiece is the only eyepiece currently available for the S.3.  As we see above, the 20-40 is a solid performer at this price point, but the 2X zoom is a little limited in magnification range.  The FOV is quite wide and similar to the Kowa’s Wide Angle Zoom in the overlapping magnification range.

20-40 zoom eyepiece

Certainly Maven didn’t equip the S.3 with a removable eyepiece just to have the one zoom, though.  If I had my way,  I would like to see an ultrawide zoom, a higher magnification zoom, and an eyepiece with a reticle. Fixed would be fine, but a zoom with a first focal reticle would be amazing.

I can imagine a reticle eyepiece being pretty helpful for determining if an Alaskan moose is 50 inch legal or a black bear across the canyon is big enough too punch a tag.


The wide field of view combined with suitable eye relief make for good digiscoping capabilities.  I was able to get good photos and video through the Maven S.3A with little vignetting.

The Maven S.3 with 20-40 wide angle zoom eyepiece is well suited to digiscoping.
The Maven S.3 with 20-40 wide angle zoom eyepiece is well suited to digiscoping.
Field Performance

I had a deer permit in Montana in a district that had some really thick cover intersected by occasional steep meadows and some burns.  I spent hours behind the Maven S.3A picking through acres upon acres of the district. What I really noticed was just how similar the S.3A felt compared to the top shelf spotters I’ve used.  It is just a quality optic.

That performance paid off when I was able to use the S.3 to observe some early rutting activity in a drainage a few miles from where I had been concentrating my efforts. Eventually monitoring that new area paid off when I came upon the nicest buck I saw in months of scouting and hunting the district.  At the check station, the biologist estimated the buck was 10.5 years old, based on the fact his molars were worn down to the gums.

Mule Deer Buck


Maven’s hunter-centered approach to sport optics is apparent in the new S.3A spotting scope.  A high performance 67mm objective spotter at a reasonable cost, combined with convenient touches like an Arca-Swiss compatible foot and tactile detents for rotating the scope, make for a scope worthy of space in the hunting pack.

While the Maven S.3 may be a bit chunky and have a somewhat limited magnification range, its optical performance in that range is competitive with even the much more expensive elite spotting scopes on the market. The Maven S.3A hits a sweet spot for many hunters trying to maximize their investment in glass.  I look forward to what future eyepieces and and accessories Maven releases for this quality spotting scope platform. Available here.

Comment or ask Matt questions here.

*Note that Maven is a Rokslide advertiser.

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Matt Cashell
Matt Cashell is a Montana hunter. Matt has traveled to all corners of his home state chasing whatever game he can. Matt has been lucky to take great trophies in Montana’s classic game species: Rocky Mountain Elk, Mule Deer, and Pronghorn. When he isn’t out chasing big game, he might be pointing a shotgun at flushing roosters, casting flies for Montana’s monster trout, or working on shooting precision long range rifles. Matt has spent more time outdoors than in through his formative years, and has deep roots in family hunting traditions garnered from years of following his father and uncle in Montana’s wild places. Family is important to Matt as he works to pass on those traditions to his five kids in the Bitterroot Valley of Western Montana, with the help of his loving wife, Heather.A self-proclaimed gear geek, Matt continues to pursue the ragged edge of hunting technology, and any small advantage or comfort that can increase his chances of backcountry success. Particularly an optics addict, Matt is always trying to see better, and find those wiley critters before they find him. It doesn’t matter what weapon is used, the hunt and wild places draw him to the woods, time after time. Going in deeper, and hunting harder is always the goal with Matt, and the pursuit of that goal never ends.