Home » Spotting Scopes » Maven S.3A 20-40X67 Spotting Scope Review – Hands-On Field Test!

Maven S.3A 20-40X67 Spotting Scope Review – Hands-On Field Test!

This article contains affiliate links. We may earn a small commission if you purchase via these links.

The day has come.

Maven has entered the interchangeable eyepiece spotting scope market with the S.3 in the angled (S.3A) and straight (S.3S) configurations.

And yes, an eyepiece is included.

maven s3a spotting scope
Image by Tina Fa'apoi (Own Work) for Target Tamers

From its 20-40x eyepiece, interchangeable eyepiece system, vari-speed focusing system, comparisons to the S.1 and CS.1 spotting scopes, there’s a lot to cover in my Maven S.3A spotting scope review.

Let’s get on with it!

Why Trust Me?

After hundreds of hours of hand-testing spotting scopes in the field and on the hunt, and thousands more hours researching, writing, photographing and creating videos about them, I feel I have earned the title of expert when it comes to optics!

Optics are not just my passion, but also my full-time job!

I get my hands on as many of the optics I test as possible (through buying, borrowing or begging!) and run them through their paces to make sure they will perform out in field.

Check out our optics testing process here.

Over a decade of experience birdwatching, glassing wildlife and hunting has been integral in putting together this Maven S.3 spotting scope review.

Quick Overview...

What I Like: Interchangeable eyepiece

What I Don’t Like: Heavy

Best Uses: Hunting, Wildlife Observation, Recreational Use, Scouting, Bird Watching, Stargazing, Target Shooting, Competition Shooting, Low Light

  • Magnification: 20-40x
  • Objective Diameter: 67 mm
  • Coatings: FMC
  • FOV: 141-100 ft/1000 yds
  • Eye Relief: 17-16 mm
  • Dimensions: 13 x 6.3 x 3.4”/60 oz

My Verdict: In total, the Maven S.3 is priced far below comparable spotting scopes of the same type. For the money, it has astounding value for its interchangeable eyepiece system. Its strong suits are in its core components, the optics and the focusing system.

Who is the Maven S.3A Best Suited to?

tripod mounted maven s3
Image by Tina Fa'apoi (Own Work) for Target Tamers

The Maven S.3A spotting scope is best suited to those who exclusively plan on using it on a tripod as it’s meant to be. Its 60 oz weight makes it difficult to hold steady in the hand, and you wouldn’t really get its full potential to appreciate the clarity and sharpness without a rock-solid tripod.

The 20-40x eyepiece that comes with the S.3 spotting scope is currently the only eyepiece available from Maven. To be fair, this is their first interchangeable eyepiece spotting scope, and it’s still new to the market.

To take away the emphasis on the weight aspect and smaller 67 mm objective lens in comparison to the Maven S.1 spotting scope, Maven must come out with additional eyepieces. I don’t imagine that they won’t given the investment and engineering it takes to design the separable two-piece spotting scope.

With a variety of new eyepieces available, the S.3 scope will appeal to everyone who knows that using a tripod will go hand-in-hand with this spotter.

As it stands with the 20-40x eyepiece, it’s a fantastic, multi-purpose spotting scope. I give my fullest recommendation to hunters, birders, target shooters, wildlife observers, and competition shooters. The optical performance does not disappoint.

How Does the Maven S.3A Perform?

excellent edge2edge performance maven s3
Fantastic off-axis performance! Image by Tina Fa'apoi (Own Work) for Target Tamers

In general, the Maven S.3 20-40x67 is a high-end spotting scope with crystal clear image quality. The optics with fluorite glass and a super smooth focusing system are its strong points. Though heavy, the premium features, like the interchangeable eyepiece system, more than makes up for it.

maven s3 bluebird
Image by Tina Fa'apoi (Own Work) for Target Tamers

Over the entire Winter, I’ve had the Maven S.3 spotting scope cover hundreds of miles with me. Its first excursion out was a late season antlerless elk (cow) hunt in December. It was a HAM hunt in AZ, and we found the herd just before first legal light about 1600 yards off thanks to the S.3A. Unfortunately, so did every other hunter that had a tag for the same hunt. Once legal light came, those who had dibs started to close in.

I was also able to digiscope my first set of decent pics (finally!) of wild turkeys with the Maven S.3 deep in the woods. Believe it or not, these pics were taken free-hand – no camera adapter to attach it to the scope, and no tripod for the scope! I was in a rush… turkeys don’t stay still.

The Maven S.3 has been a worthy companion during my Winter adventures. Its weight has been a bit of a sore point lugging it around everywhere, but when I’m able to dial in for the resolution I was getting, all thought of its heft disappeared.

The optics exceeded my expectations during my months of hands-on field testing. The fluorite glass, vari-speed focusing system, and even the magnification range proved worthy of high praise over and over again in the field.

The S.3A spotting scope is a value buy that could very well be an all-purpose spotting scope, and the last spotter you may buy yet.

Features & Benefits

Interchangeable Eyepiece

maven s3 spotting scope removeable components
Detachable eyepiece & rubber eyecup - Image by Tina Fa'apoi (Own Work) for Target Tamers

Overall, the remarkable feature about the Maven S.3 spotting scope that sets it apart from Maven’s other spotting scopes is the interchangeable eyepiece system. A mid-range magnification eyepiece is included with the S.3 body.

It’s yet to be seen what other eyepieces Maven is yet to offer for this scope, though I do hope we see a 20-60x or 20-80x eyepiece in the future.

The entire ocular bell is extremely well constructed. It’s heavy in its own right with 5 groups and 7 elements in its eyepiece assembly.

It’s secured to the spotting scope with a locking/unlocking collar. It’s well-made and hasn’t once unintentionally unlocked, come loose, or popped off.

To remove the eyepiece, twist the lower ring/collar to the unlock position. Twist the ocular bell in the counterclockwise position to remove it. To put it back in, you must insert the ocular bell and twist it clockwise until it sets into the threads and does not pull out. Then you can lock the collar. It’s all rather elementary once you get your hands on it.

maven s3 removable eyecup
Removeable eyecup - Image by Tina Fa'apoi (Own Work) for Target Tamers

As is standard for Maven optics, I really like that the S.3 has a removeable rubber eyecup. Twist it off and you can clean around the eyepiece, the rubber cup, and the threading. This small maintenance step means having your spotting scope around for a long time and that it will perform at its best every single time.

S Series Optics

maven s3 min mag vs max mag
20x VS 40x - Image by Tina Fa'apoi (Own Work) for Target Tamers

The Maven S.3A is part of the S series. Other than the S.2 that has Abbe-Koenig prisms, the scopes have Schmidt-Pechan prisms complete with dielectric and phase correction coatings. Unlike the C series of scopes with ED glass, the S series has fluorite glass, and the difference is unparalleled.

With the ability to home in for maximum resolution whether I’m looking at groups at 25 yards with a 1x red dot sight or counting points on big game beyond 800 yards, I was always astounded by the clarity and sharpness.

The vari-speed focusing system is exceptional. Course adjustments are fast and easy to make and dialing in for maximum detail by taking it slow proved more than worth it. I usually have a hard time getting crisp resolution at max magnification on spotting scopes, and the S.3A did not disappoint. Other than environmental factors contributing to optical distortion, like mirage, the Maven scope’s strongest asset is the optics.

I did not see any chromatic aberration even while digiscoping. This made for an exceptional experience while birdwatching. The depth of field is actually very good even though you can see some spherical aberration from the camera in the photos. Focusing in for several hundred yards away and looking to the lower third of the FOV of close-up targets, the image is about as tack sharp as it can be.

Build Quality

Maven S3A angled spotting scope
Image by Tina Fa'apoi (Own Work) for Target Tamers

Everything about the Maven S.3A spotting scope is high end. It’s made with Japanese components and assembled in the USA. It can be deduced that quality assurance is inspected and performed right here in the United States.

The S series of spotting scopes are all made with an aluminum, polymer, and magnesium chassis. This provides a strong, lightweight, and rugged frame to withstand vibrations and shock and protect the optical elements. It’s also waterproof and has been nitroged purged for fogproof protection.

The rubber armor is about 3.175 mm thick (I measured about 2/16ths of an inch). It’s tight to the frame, is scratch-resistant, sheds water quickly, and in my experience with Maven optics, it does its job extremely well. I’ve never had an issue with the rubber armor coming loose, cracking, fading, or splitting over time.

I am sorry for one part of the build quality and that would be the finish on probably the only part of the scope that can show up any sort of scratches and wear – the rotating ring. It’s my fault.

Wear on the maven s3
Scratches on the rotating collar finish - Image by Tina Fa'apoi (Own Work) for Target Tamers

During one particular trip out, the Maven CS.1 spotting scope came along for a comparison session. I believe the tripod mount beat up this part of the S.3A spotting scope. I should have had them with the drawstring bags on (I didn’t because I like to be ready to spot and digiscope in an instant) or at least had them separated.

Lesson learned – other metal parts will not play nice with the S.3 in this one spot. Don’t do as I do, do better.

Focus & Magnification Components

I’ve already spoken on the performance of the vari-speed focusing system, but I also want to mention how smoothly it moves. There were times I accidently nudged the focus when I didn’t mean to. Its location is ergonomically strategic as my hand naturally lays there during use. I found myself making fine adjustments with my third and fourth fingers which felt like a very natural experience.

I like that the focus and magnification rings are large – there’s no guessing or having to ‘feel’ your way to them while you’re using the spotting scope. There are no stiff spots or any slop/play in either ring. The magnification is a little stiffer than the focus ring which is perfectly acceptable. I haven’t detected any tunneling throughout the entire magnification range.

Moving Components

Maven s3 extendable sunshade
Image by Tina Fa'apoi (Own Work) for Target Tamers

I like the extendable sunshade on the objective end of the scope. It extends out about an inch providing almost a 2” depth to the objective lens. I didn’t really need to use it in the field, but this will be very nice to have when the conditions call for it.

The rotating knob is especially convenient for angled spotting scopes. I found myself using this while duck watching at the ponds. Between sitting, standing, and trying to avoid craning my neck, being able to rotate an angled spotter is invaluable for comfort.

rotating collar knob on maven s3
Image by Tina Fa'apoi (Own Work) for Target Tamers

It will be indispensable to get the best viewing angle regardless of an awkward position you may be in, say in a blind, around a bush, and when looking at targets at an angle of depression (below your horizontal line), etc.

Providing for use with glasses or without, the Maven S.3A spotting offers up 17-16 mm of eye relief. I want to say it’s a little more than that. Though my glasses are against the eyepiece of the scope, I don’t need to force or push my face into it to get the entire FOV. It’s actually quite comfortable, and I want to say it’s more like 19 mm with the eyecup retracted all the way down.

Multi position eyecup maven s3
Retracted eyecup (left) VS extended eyecup (right) - Image by Tina Fa'apoi (Own Work) for Target Tamers

The eyebox does get a little bit tight at max magnification. I’ve experienced much worse, and the eyebox at 40x isn’t all that bad honestly. I can observe just fine with minimal movement from touching the eyecup and the focus ring, and I’m not digging my eyeball into the eyepiece to get an aberration-free FOV. It’s actually very good, and with the kind of resolution provided at max power, I don’t actually have any real complaints about the eye relief.

Even so, I have a neat trick to share.

I’ll crank up the power and fine focus for the target. Then I retract the eyecup all the way in and that way I can cleanly and nicely observe at max 40x power. This eliminates any vibrations that are coming from me either from focusing or my face against the eyecup. This is a trick I used during lunar observation.

Shooting Range Performance

maven s3 spotting groups at 25 yds
.22LR holes at 25 yds 20x (left) VS 40x (right) - Image by Tina Fa'apoi (Own Work) for Target Tamers

Overall, the fantastic optical quality of the Maven S.3A spotting scope is the reason why it’s excellent for seeing bullet holes at the range. It clearly has the magnification and resolution to see .22LR holes on paper to 100 yards and beyond.

context pic for shooting range
Context pic - red 25 yds, white 100 yds - Image by Tina Fa'apoi (Own Work) for Target Tamers

I took a target out with an M&P 15/22 outfitted with the Swampfox Raider 1x20 Micro Prism red dot sight. The goal was to just punch some holes in the target for the purpose of testing out the S.3A scope’s ability to spot groupings and reduce trips walking downrange.

Though it doesn't seem like it from the images (digiscoping, website formatting, resolution loss, etc.), I could clearly see the bullet holes in person.

maven s3 spotting groups at 100 yds
.22LR holes at 100 yds 20x (left) VS 40x (right) - Image by Tina Fa'apoi (Own Work) for Target Tamers

The results? The Maven S.3A is the best scope for spotting groups that I’ve ever had the pleasure of using. I have absolutely no doubt that you can take the S.3A further than 100 yards for spotting bullet holes on paper targets. Shoot ‘n see targets would definitely help to push that distance.

Lowlight Performance

maven s3 moon
S.3 tripod mounted but digiscoping free-hand. Crystal clear clarity through scope - Image by Tina Fa'apoi (Own Work) for Target Tamers

The lowlight performance of the Maven S.3 spotting scope is exactly what I expected. The S.3 was still going strong after last legal light. The resolution is exceptional, and even though the digiscoping doesn’t show it, I have a full FOV with outstanding detail for the conditions.

Technically, it’s the early part of twilight when the sun has gone down below the horizon and I’m observing a small shed about 157 yards away.

The moon is out, so I focus on that for a little bit while the sky continues to darken. Given that I don’t have a moon filter for the objective, it’s difficult to show the exquisite detail I see in person due to the brightness of the moon and the camera’s limitations. The 40x of the S.3 spotter really brought to attention the Tycho Crater and its ejecta rays.

I also couldn’t see what I think was Jupiter at the time with the naked eye and didn’t even know it was there until I put the spotting scope to the skies.

Once it was definitely deeper into the twilight hours I focused on some storage sheds about 2000 yards away. What I could see in person was impressive given how dark it already was.

Maven S.3 VS S.1

Maven s1
Maven S.1A in action - Image Credit: Maven

The Maven S.3A 20-40x67 spotting scope is bigger than the S.2 12-27x56 but smaller than the S.1 25-50x80. Honestly, the dimension and weight differences between the S3 and the S1 are almost a wash even though the S1 is about 2” longer than the S3.

Optically, they’re made the same but due to the different configurations, the S3 spotting scope provides a few more advantages at the cost of magnification and a smaller objective.

The S3 has a wider field of view of 141-100 ft at 1000 yards versus the 115-84 ft of the S1. As far as brightness goes, you could call it even as you won’t be able to notice a difference between the two in this regard in daylight conditions.

s1 vs s3
S.1A (left) - Image Credit: Maven. S.3A (right) - Image by Tina Fa'apoi (Own Work) for Target Tamers

The real telling will be in lowlight and is where the S1 has an advantage. Though some eyes might not be able to tell a difference between the two, the S1 can discern more resolution in lowlight. For most, you will see an improvement in those last legal light minutes and twilight conditions to squeeze out a little more detail.

Since the S3 is still just as heavy and almost as big as the S1, I’d recommend disregarding comparing size altogether. The real benefits of the S3 over the S1 is the generous FOV and of course the interchangeable eyepiece. Though excellent for hunting, wildlife observation, and the target range, I think it will be great as an all-purpose spotting scope for a wide variety of applications.

maven s1 spotting scope
Maven S.1A in action - Image Credit: Maven

For a small difference in cost, you get 10x more magnification, a larger objective lens, and better lowlight performance. It’s worth spending the small increase if you’re after bigger performance especially if you’re considering a spotting scope for a specific purpose. Of course it will work for other applications too, and it will be a workhorse for the trophy hunter.

Maven S.3 VS CS.1

maven s3 vs cs1
S.3 in the back. CS.1 in the front - Image by Tina Fa'apoi (Own Work) for Target Tamers

The Maven CS.1 15-45x65 spotting scope is a trooper. It’s one of the best spotting scopes under $1000 that’s worth it. It’s unfair to compare it to the Maven S3 20-40x67 spotting scope, but I highlight the traits and limitations of both.  

In the field, the CS.1 performed very admirably at 40x magnification next to the S3. I often took it to 45x (max mag) but the optics are maxed out at this point and environmental factors contributed to a degraded image. It’s no surprise that even though the S.3 was maxed out at 40x, it still performed significantly better at max mag than the 45x max of the CS.1.

Though the chromatic aberration is pronounced at 45x in the CS.1 spotter, most of this was due to digiscoping. I’d say less than a third of that was actually present. Still, the S3 did not display any noticeable chromatic aberration even at max magnification.

The focusing mechanism can’t be compared between the two. The S3 has far better focusing that allows for fine adjustments. I was left wanting with the CS.1, and part of the resolution difficulties at max mag is also due to the fact that it only has ED elements but does not have fluorite glass like the S3 does.

s3 vs cs1 marker sign 377 yards
S.3 20x (left) 40x (middle) VS CS.1 45x (right). "17" marker sign at 377 yds - Image by Tina Fa'apoi (Own Work) for Target Tamers

When it came to handling, it should be obvious that the CS.1 is far easier to work with as a handheld monocular. Side by side, I found myself going for the CS.1 just because it’s lighter, I could grab it in an instant with ease, and the lower 15x magnification provides for a huge 174 ft FOV.

The S3 is not only bigger than the CS.1, it’s significantly heavier weighing 20 oz more. On the tripod, weight and size becomes less of an issue. The CS.1 is obviously nicer on your back when you’re scouting and creeping in the brush during a hunt, but the extra weight of the S3 is worth it for the noticeable improvement in optical performance.

The final comparison of note is the cost difference. The CS.1 is a mid-tier spotting scope that’s priced competitively with comparable spotters. If you’re looking for a travel spotting scope or something that you’ll be using as a handheld about 20-40% of the time for a variety of applications, the Maven CS.1 has earned my hard-won recommendation.

If you want the best of the best and are willing to pay for it, upgrade to the Maven S.3.

Limitations of the Maven S.3A


weighing the maven s3a spotting socpe
Weigh-in: 59 oz - Image by Tina Fa'apoi (Own Work) for Target Tamers

In total, the Maven S.3 spotting scope is heavy at 60 oz. It’s been mentioned more than once throughout my field test review. Many critics will complain that it’s just as heavy as the larger S.1. That is true. However, the S.1 doesn’t have an interchangeable eyepiece feature.

The optical specifications will change with the eyepiece. So even though the 20-40x eyepiece that is currently offered with the S3 is limited to 40x magnification, there could be yet a higher-powered eyepiece in store.

The objective isn’t as large, and you might suspect that this should have saved some weight. But it appears that the S3 uses the same prisms and internals as the higher powered S1. This must account for a good portion of its weight.

Put the S3 on a tripod like how it and the S1 are supposed to be used. Revel in the fact that you can change out the eyepiece in the future without buying a whole new scope. Problem solved.

YouTube video

Popular Questions About the Maven S.3A

How Much does the Maven S.3 Spotting Scope Cost?

The Maven S.3A and S3.S spotting scopes are priced under $2000. Though still expensive for a spotting scope, the best often are. However, it’s still cheaper than competitive high-end spotting scopes and especially so with those that have the interchangeable eyepiece system.

Is the Maven S.3 Good for Back Country Hunting?

Personally, I think the Maven S.3 is excellent for backcountry. It’s not the lightest spotting scope especially considering that you need to haul a tripod too. However, its optical performance covers mid to long-range distances with ease with the resolution needed to make the pack-out worth it.

Can You Use the Maven S.3A Without a Tripod?

In general, to get maximum performance out of the Maven S.3A spotting scope, you should tripod mount it. This provides the most stable viewing platform to see as much detail and resolution as possible.
However, I’ve used it as a handheld usually while leaning on a front end of a truck or kneeling with my elbows on my knees for support. It’s better at the low powers but much harder to maintain a vibration-free image at the higher powers.

Can the Eyepiece Accidentally Get Lost?

The eyepiece is held secure on the Maven S.3 body complete with a locking mechanism. It’s highly unlikely that it will get lost or become loose even with it being in the unlocked position. The locking mechanism is a 2-part system that has not once failed during months of field testing.
You must first disengage the lock to ‘unlock’ and then physically twist the entire ocular bell off the scope body. It’s decently stiff to twist it off, so I can safely say that it won’t accidentally come off or get lost during use.

Is the Maven S.3 Covered by a Warranty?

The Maven S.3 spotting scope along with all of Maven’s optics are covered by their lifetime warranty. It’s an unconditional warranty, so you don’t need to provide a receipt or proof of where you purchased it from.
It’s an awesome warranty and is up there with the industry-best warranties that you can find in the optics market. If there’s an issue, Maven will repair or replace it. They also have a demo program if you’re interested in testing it out before you commit to buying it.

Getting Personal with the Maven S3

maven s3 in the morning
Image by Tina Fa'apoi (Own Work) for Target Tamers

The S3 is for those who want premium performance from a premium scope. It’s big, heavy, and you could say expensive, but for all that it offers along with the prospect of additional eyepieces in the future, the S3 has the value factor.

Complete with stellar optical performance, the Maven S.3A 20-40x67 spotting scope will be a one-time purchase – there’s no need to seek out another for a long time to come.

I’ll be sorry to see this spotting scope returned because it is one of the best spotting scopes I’ve had the pleasure of personally field testing. We’ve had ‘a first’ together, spent many months together, and hunted together. What the S.3A and I have, it’s a friendship at this point. I can bet you’ll feel the same way too when you rack on miles with this high-end spotter.

maven s3a 20-40x67 spotting scope
Image by Tina Fa'apoi (Own Work) for Target Tamers

Many thanks to Maven for sending me this spotting scope to field test. Please note, even though this product was loaned by the manufacturer, all opinions expressed are my own and are not in any way influenced by the manufacturer.

Further Reading

Photo of author

Tina Fa'apoi - Expert Optics Tester

Tina is a renowned expert in optics, having written hundreds of articles for Target Tamers over the past eight years and owning an extensive collection of optic's including binoculars, rifle scopes, red dots, spotting scopes and rangefinders. With years of experience in creating instructional videos and field-testing various optics, Tina brings a wealth of practical and theoretical knowledge to the field.

Never Miss a Thing!

Get Our Latest Guides & Field Tests Straight to Your Inbox

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

As Featured Footer Image