KOWA Prominar TSN-99 & TE-80XW Eyepiece Review

KOWA Prominar TSN-99 & TE-80XW Eyepiece Review

In early September 2021 I was very fortunate to get my hands on the brand new Kowa Prominar TSN-99A and the much awaited TE-80XW eyepiece just prior to an action packed, two week hunting expedition with elk hunts in Wyoming and Idaho sprinkled in with a bit of spot and stalk antelope action.  I glassed elk, mule deer, mountain goats, antelope, and coyotes in about every conceivable lighting condition with the new Kowa spotter and even snuck in a few days hunting mule deer in Idaho.

Kowa Prominar TSN-99A & TE-80XW Eyepiece

Kowa’s new TSN-99 spotting scope is the crown jewel of their renowned line-up.

The new TSN-99A supplants the TSN 883/884 as the flagship model in Kowa’s renowned line-up of spotting scopes.  It’s crowned with a massive 99 mm fluorite crystal objective lens, second in size to only the mighty 115 mm Swarovski among mainstream sport optics offerings. 

TSN-99 vs Swarovski 115

The Kowa TSN-99 is second in size only to the Swarovski 115 Objective as seen mounted to a BTX next to the Kowa TSN-99 here.

The TSN-99 is available in Angled (A) and Straight body (S) versions to suit both the hunting and birding markets.  The body is constructed of thixomolded magnesium alloy machined to exacting tolerances.  The exterior is familiar and in-line with previous non-armored Prominar models with a few minor cosmetic updates to blend the rotating scope collar with the main body.  The TSN-99A or 99S body retails for $3,999.00.

TSN-99A awesome in low lightThe TSN-99’s sculpted magnesium body is sleekly designed while still rugged and easily recognizable as a Kowa.

The TSN-99 is compatible with the venerable TE-11WZ zoom eyepiece.  On the TSN-99 the TE11WZ provides 30 – 70x magnification and a field of view (FOV) of 105 feet at 1000 yards at 30x and 60 feet at 70x.  The current TE-11WZ eyepiece is not yet marked to show the power range accurately on the TSN-99 since it bumps up from 25 – 60x on the legacy TSN 88 and 77 series scopes, but Kowa has promised new TE-11WZ eyepieces with updated laser markings for the TSN-99 that will be shipping soon.


New laser marks are being added to the new “TE-11WZ II” eyepiece so it will accurately show magnification on the TSN-99 as well as the TSN-88’s and 77’s.  It should be available by November 2021.

TE-80XW – Wider is Better!

As exciting as the TSN-99 is, the new, eXtreme Wide angle eyepiece, dubbed the TE-80XW, might deserve equal or more attention for its revolutionary optics.  It’s a fixed power eyepiece with an incredibly wide field of view for 40x magnification (117 feet at 1000 yards!).  That’s 12’ more viewing at 40x than you get with the TE-11WZ at 30x.  Side by side with a Swarovski ATX 95, I had to turn the Swarovski down to 30X to see about the same FOV.  That’s a wide advantage!  The TE-80XW retails for $699.00 – the same price as the TE-11WZ.

TSN-99 vs. TSN-88The TE-80XW is equally at home on the Kowa TSN-99 (left) at 40X or on the TSN-88 (right) for 35X magnification.

Mounted on the TSN-88, it’s even wider because the magnification is reduced to 35x.  Although specs were not available to quantify the FOV on the TSN-88 at the time of this writing, I suspect FOV is in the 135’ range.

Glass them up with a Kowa TSN-99A with TE-80XWHoyt President, Zak Kurtzhals got a chance to use the TSN-99 while elk hunting with me in Wyoming and Idaho.

Sharpness of the TSN-99 with the TE-80XW is exceptional.  Colors render very naturally albeit ever so slightly biased toward warmer hues.  Chromatic aberrations are never an issue and can only be detected when your eye is well off center in the eyepiece while viewing high contrast objects.  Contrast is excellent and I found looking deep into shadows was better in the TE-80XW eyepiece compared to the TE-11WZ and I could more easily make out details in those dark areas. 

TSN-99 Pros/Cons

The tripod foot has unfortunately not been updated to an integrated QD base like the Swarovski scope foot with its deliberate ARCA compatible base.  We’re stuck with the hassle of the never-tight-enough adapter plate on the new TSN-99.  It would have been such an easy feature to implement to eliminate one of the most frustrating aspects of using a large spotting scope.  Thus, it’s probably my single biggest complaint about the new Kowa TSN-99.  On numerous occasions I had to unmount the scope and re-tighten the (expletive) adapter plate screw.  Yes, I’m aware there are adapter plates designed to eliminate the issue with ledges and set screws, but who wants to have to buy a specialty plate to fix a problem that shouldn’t be a problem? 

Kowa Prominar TSN-99AThere’s not much to complain about with Kowa’s TSN-99, but I would like to see the tripod foot molded to fit ARCA tripods and a rubber armored body.

It’s a great looking scope, but I would prefer a rubber armor coating to absorb some of the abuse a scope sees in the field.  Rubber armoring adds some weight, but it just makes a scope feel more rugged and the added grip and insulation against the cold are nice too.  I found myself being extra careful with the Kowa even though I drug a metal bodied Swarovski AT-80 around the hills for almost 15 years without issue.

The TE-XW 80’s eyepiece ocular lens is so big it can feel a bit unnatural at first having to look so far from center to see the edges of the massive field of view.  I don’t mean to say that’s a bad thing, but it is different at first.

TSN-99 is precisely built with exacting tolerances and beautiful fit and finish.  Merely sliding the sun-shade out is evidence of this.  It moves smoothly as if it’s gliding on an air hockey table and then locks into place at full extension with a perfectly audible and satisfying click.  The rotating tripod collar is also very precisely fit to the body.  Even with the locking screw loose, there’s no apparent slop that would cause movement of the scope should the wind pick up.  The detent clicks for the rotating collar could be a little more positive to confirm the scope is in the upright or 90 degree orientation, but you can feel them if you’re paying attention.

Size Comparison TSN-99Here you can see the TSN-99 (2nd from the right) next to a Swarovski ATX-95  (far right), and TSN’s 88, 77, and 55 on the left in descending order.

The rubber dust ring around the eyepiece fits snugly and keeps dust out of the mating surfaces between the scope body and eyepiece which is important if you happen to have both eyepieces and switch them back and forth.  This ring can also be unthreaded to allow cleaning the mating surface.  Removing the dust ring is required to install the TSN-PA7 digi-scoping adapter for DSLR or mirrorless cameras.   

Kowa TE-80XWThe rubber dust ring trim around the eyepiece keeps dust and debris away from the eyepiece to scope body mating surface.  The markings on the rubber eyepiece are from the lens cap.

I appreciate the dual focusing mechanism with coarse (fast) and fine focus capabilities.  If anything could be improved here, I’d ask Kowa to please make the fine focus even finer!  With a scope this sharp it seems like I wanted to focus it more often, knowing there was always a bit more detail I could tune in with the focus knob. 

Coarse and fine focus knobsDual focus knobs allow for quick and precise focusing, although I’d prefer if the fine focus was geared even lower – Granny focus for me please!

Which Eyepiece Should You Buy for the Kowa TSN-88 or TSN-99?

That may be the most difficult question to answer with this scope.  You’re going to get a little more sharpness and a much wider view at 35x on a TSN88 or 40x with the 80XW on a TSN-99 compared to the 11WZ.  However, you sacrifice the ability to zoom.  There is a trade-off, regardless of which you pick.  It’s the same debate photographers wrestle with when deciding whether to purchase a set of premium prime lenses for their camera or go with a high quality zoom lens for convenience. 

Kowa did a nice job making the fixed power lens exceptionally wide, so the trade off in FOV is minimized. So, when you’re trying to find game in the scope the wider FOV allows you to cover the same amount of country as a 30X scope at the higher 40X power.  They also chose a good midpoint in the typical range of usable power.  I could argue that 30/35x would have been better for general glassing, but I think you’d be left wanting more power to zoom in to analyze antlers at long distance. 

TE-XW80 EyepieceI couldn’t figure out why I was getting confused about the name until I realized Kowa calls it the TE-80XW in their literature, but the eyepiece I had is laser marked TE-XW80.

Personally, I’m going to stick with the new TE-80XW because I lean toward the highest quality image possible.  I use 12 or 15x binoculars on a tripod for most of the glassing work and use the spotter to pick apart particularly dense areas and brushy draws.  I am confident I’ll be able to judge antlers good enough to make a go or no-go decision at 40x. 

With that in mind, I still think the TE-11WZ will be a more popular choice for most sportsmen who appreciate the ability to zoom out to glass and zoom in to analyze those pesky stump deer and put the mental tape on every inch of those far-away antlers.

The best way to know for sure is to RENT both eyepieces with the scope body of your choice and try them out side-by-side, on a hunt.  Rent Outdoor Gear has affordable rental rates on premium optics and they offer a fantastic Keeper Program that allows you to apply up to 7 days of the rental cost toward a purchase.  So, whether you need to rent a premium optic for a once in a lifetime hunt, or you’re looking to make the right buying decision on new glass to last a lifetime, you should consider using our service.

Wondering which is better – Kowa TSN-99 vs. Swarovski ATX 95 or STX 95?

I’d say you’re all so predictable, but of course, answering that question was at the top of my list too… Who doesn’t love a great fight?  Predictably, there’s no straight answer to that question; they both have their strengths and weaknesses.  In a straight-up, head-to-head comparison, you would be hard pressed to pick a winner between the ATX95 and the TSN99 equipped with the TE-11WZ eyepiece.  They’re so close it’s not worth debating under most glassing conditions.  There are a few characteristics of the Kowa’s image that are more pleasing to my eye, but I wouldn’t go as far as saying everyone would agree.

Kowa TSN-99 vs Swarovski ATX-95There are no losers here; both scopes will be the envy of hunting partners everywhere.

With the 80XW on the TSN99 (40x) and the ATX-95 zoomed to 40x, the Kowa wins easily because of its significant FOV advantage, but it’s also brighter and clearer edge to edge.  However, the ATX can mitigate the FOV and narrow brightness advantage with a quick turn of the power ring down to 30X or crank up to 70X for a much closer look at anything you might question at a lower power.

The TSN-99 edges out the Swarovski ATX-95 looking toward the sun at certain angles where I picked up more sun flair in the ATX-95.  It wasn’t significant, but it was noticeable.  This may be due in-part to the simpler design of a fixed power eyepiece with presumably fewer glass elements to refract light.  The Swarovski also has a protective glass element over its massive fluorite front objective lens to protect it.  This protective layer comes at a slight cost of light transmission.  That minor loss in light transmission and fidelity might save you a much more expensive lens repair if you happen to damage it, whereas the Kowa’s fluorite front objective element is exposed letting more light in and keeping the overall image as pristine as possible. 

Big Objective SpottersThe Swarovski 95 on the right has a protective glass layer over the objective to prevent scratching the expensive fluorite lens, while the Kowa’s 99 objective is exposed maximizing brightness and image quality

The Swarovski ATX renders colors slightly cooler than the Kowa TSN-99.  To my eye the Kowa produces slightly more natural color that matched what I see with the naked eye better.  The warmer tone of the Kowa contributes to its brighter appearance whether using the TE-11WZ or 80XW eyepiece.

The Swarovski ATX/STX/BTX system, with its vast range of objectives, still is at the top of the heap in terms of flexibility and its ability to be whatever scope you need for any type of hunt, assuming you can afford to add the necessary accompaniments.

Digi-scoping with the TSN-99 and TE-80XW

Unfortunately, I grabbed the wrong Phoneskope adapter ring for my initial two week outing, so I didn’t get nearly as many photos through the scope as I would have liked.  The correct Phoneskope adapter is the C3-26A and it works on both the TE-11WZ and the TE-80XW eyepieces.  Luckily, I also brought along the appropriate Kowa TSN-PA7 digi-scoping adapter for my Nikon DSLR camera.

I did manage to shoot some photos with my DSLR, but compared to a Phoneskope, mounting a big camera to the scope is a lot more cumbersome and time consuming.  The TSN-PA7 adapter is awesome if you’re dedicated to taking great photos or documenting your birding adventures and you’re less concerned with finding game than I am. 

I have a much harder time locating and tracking a subject watching the camera screen – which isn’t as bright or easy to view as an iPhone.  Furthermore, my DSLR is big and heavy and has a mechanical shutter.  Lightweight hunting tripods and a 2000 mm effective focal length lenses don’t go together that well.  They’re especially finicky with a heavy camera cantilevered on them with a shutter that sets off a small vibration every time it fires.  Not the best scenario for tack sharp images, but I got a few decent shots, but they don’t do justice to what the eye sees through the scope.

Digiscoping with a TSN-99 and TSN-PA7 adapter With a DSLR you can get some great photos using the TSN-PA7 adapter with the Kowa TSN-99.  All these were shot with the TE-80XW between about 40 yards (rock with lichen) out to about 4 miles (hikers on the summit).

If you really want to shoot great photos through the scope, you’ll want a lighter camera with an electronic (digital) shutter, in camera image stabilization, and a rock steady tripod like an RRS TFCT-34 that PRS shooters use for competition.  Aside from that, a camera with excellent high ISO performance (low noise), so you can utilize a fast shutter speed is going to help optimize image quality.  A balance rail would also help stabilize the whole rig.  Kowa sells the TSN-DA3 which is designed to stabilize digiscoping setups.  It’s designed for straight bodied scopes, but I think it would provide some much needed support and balance when mounting any type of camera to a straight or angled scope.

Manually focusing is required when mating a DSLR with the Kowa TSN-PA7 adapter.  This is tedious because touching the scope causes the image on the screen to shake when you’re making fine focus adjustments.  You also need to zoom-in on the camera’s image using live-view and make small adjustments checking focus again after the camera settles.  Blame my lack of patience and greater desire to find game for the lack of digi-scoping photos.  Video through the scope is a better bet with an old school DSLR like my Nikon D750. 

The typical hunter is going to get excellent results using a Phoneskope with this rig, so it’s probably not worth the effort and expense of building a pro digi-scoping rig unless you’re trying to achieve magazine quality shots – and even then, with a newer iPhone/Phoneskope combo, you can get stunning results with far less effort since your phone will auto-focus even if the image is not perfectly focused for your eye.

Shooting Straight

There’s a lot to consider in making a premium optics decision, but for simplicity’s sake I will distill it down to this… If you’re a one scope kind of person, then a Kowa TSN-99 is going to be a fantastic option to consider, fitted with your choice of the variable magnification TE-11WZ or the fixed power TE-80XW.

If you’re a guy that needs an angled 65mm spotter for a backpacking trip one week and a BTX-95 for the next, then only a Swarovski A/S/B/TX has that flexibility.  If you’re still unsure which scope and eyepiece is right for you, I personally guarantee you’ll save time, and money and eliminate buyer’s remorse by renting and trying them out in the field on your next outing.  Don’t forget, 7 days of your rental can be applied to a purchase of rented gear with the Keeper Program.

Kowa TSN-99 ObjectiveWhile the choice isn’t as immediately clear as the TSN-99 objective lens, renting a scope and trying it out in the field will certainly help you make a sound buying decision.

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