Nikon Aculon A211 10x50 vs Nikon Action EX 8x40
Quick take: The Nikon Aculon A211 10x50 costs $20 less; the Nikon Aculon A211 10x50 reaches farther (10x vs 8x); the Nikon Action EX 8x40 has a wider field of view (430 vs 341 ft @ 1000 yds).
Field of view, to scale
Top-down view · drawn to true scale — no exaggeration
Which one to buy
Rain is the first question. The Nikon Action EX 8x40 is waterproof, fogproof and nitrogen purged; the Nikon Aculon A211 10x50 is none of those, and its owners say a soaking or a cold-to-warm transition can end its day. For $20 more, the Action EX also brings 17.2mm of eye relief against the Aculon's tight 11.8mm, so eyeglass wearers see the whole field instead of losing a big chunk of it. Both are discontinued, so new stock of either may be hard to find.
The two share a bright 5mm exit pupil and Porro prisms with the depth owners love, and both are heavy, at 31.7 oz and 30.1 oz. The Action EX's 430 ft field is very wide, and owners who have tried both say its eyepieces give a larger, clearer sweet spot with less color fringing than the Aculon line. Its weaknesses are stars blurring in roughly the outer 20% of the field, boxy bulk, and the Porro risk of collimation being knocked out by a hard drop.
The Aculon 10x50's case is cheap aperture for the night sky. Astronomy owners recommend it as a first stargazing binocular and pair it with a tripod, because 10x at 31.7 oz shows hand shake. Its field edges go soft, the moon and streetlights show color fringing, and there is no tripod adapter in the box.
For nearly everyone, the Action EX 8x40 is the better buy: weatherproof, glasses-friendly and easier to hold. The Aculon 10x50 only makes sense for a budget stargazer who observes from a dry backyard without glasses and wants the extra reach on a tripod.
Nikon Aculon A211 10x50
For a dry-backyard stargazer on a strict budget who will add a tripod and doesn't wear glasses, it's cheap aperture; it is discontinued.
Nikon Action EX 8x40
Worth the extra $20 for anyone who goes outside in weather or wears glasses, while stock lasts; it is discontinued.
| Spec | Nikon Aculon A211 10x50 | Nikon Action EX 8x40 |
|---|---|---|
| Approx. price | ~$140 | ~$160 |
| Use case | General Purpose | General Purpose |
| Magnification | 10x | 8x |
| Objective | 50mm | 40mm |
| Exit pupil | 5.0mm | 5.0mm |
| Field of view | 341 ft @ 1000 yds | 430 ft @ 1000 yds |
| Eye relief | 11.8mm | 17.2mm |
| Close focus | 23 ft | 16.4 ft |
| Prism | Porro | Porro |
| Glass | Eco-Glass | Eco-Glass |
| Coating | Multi-Coated | Fully Multi-Coated |
| Weight | 31.7 oz | 30.1 oz |
| Dimensions | 7.0 x 7.8 in | 5.4 x 7.4 in |
| Warranty | Limited Lifetime | Limited Lifetime |
Feature comparison
Nikon Aculon A211 10x50
- ✗ED Glass
- ✗Phase-Corrected
- ✗Dielectric Coating
- ✗Waterproof
- ✗Fogproof
- ✗Image Stabilized
- ✓Tripod Adaptable
- ✗Magnesium Body
- ✗Locking Diopter
Nikon Action EX 8x40
- ✗ED Glass
- ✗Phase-Corrected
- ✗Dielectric Coating
- ✓Waterproof
- ✓Fogproof
- ✗Image Stabilized
- ✓Tripod Adaptable
- ✗Magnesium Body
- ✗Locking Diopter
What birders say
Nikon Aculon A211 10x50
- ✓Outstanding optics per dollar - astronomy forum members recommend it as a first pair and say it would make a good investment for an astronomy club outfitting beginners
- ✓Big 50mm objectives and a 5mm exit pupil deliver genuinely bright images for stargazing and dusk wildlife at a budget price
- ✓BaK-4 Porro prisms give the image a depth and 3D quality that budget roof-prism binoculars can't match
- ✓Aspherical multilayer-coated eyepiece lenses keep the center of the field sharp and distortion low
- ✓374 ft field of view is wide for a 10x50 at this price
- ✓Reviewers describe the frame as sleek, solid, and well made - it doesn't feel like a $140 binocular in the hand
- ✓Tripod adaptable, which matters because that's how it performs best on the night sky
- ✓Stargazers who've compared it have preferred it over pricier alternatives for casual astronomy
- ✗Not waterproof or fogproof - a soaking or a cold-to-warm transition can end its day, which rules it out as serious field glass
- ✗Tight 11.8mm eye relief is the most common complaint - eyeglass wearers lose a big chunk of the field of view
- ✗Heavy at 31.7 oz, and reviewers note it lacks any pretense of portability
- ✗10x magnification in a 2 lb body is genuinely hard to hold steady - owners consistently say handheld shake is noticeable, as with all 10x50s
- ✗Edges of the field go soft - star fields blur noticeably away from center
- ✗Chromatic aberration shows on bright, high-contrast targets like the moon and streetlights
- ✗Turn-and-slide rubber eyecups are less precise than click-stop twist-up designs
- ✗No tripod adapter in the box - it's a separate purchase you'll probably want
Nikon Action EX 8x40
- ✓Exceptionally wide 430 ft (8.2 degree) field of view - forum users describe the view as extra wide with extremely bright colors
- ✓17.2mm eye relief is outstanding at this price and lets eyeglass wearers see the whole field
- ✓Fully waterproof, fogproof, and nitrogen purged - real weather sealing that the cheaper Aculon line lacks
- ✓Owners who have both lines prefer the Action EX over the Aculon: improved eyepieces, a larger and clearer sweet spot, and less chromatic aberration
- ✓BaK-4 Porro prisms deliver the bright, deep, 3D image quality that makes porros beloved at budget prices
- ✓Reviewers call it an outstanding entry-level binocular - optically good and robustly weather resistant for the money
- ✓Rugged rubber-armored body that shrugs off field abuse
- ✓Tripod adaptable, and the bright wide field makes it a pleasant casual astronomy glass too
- ✗Edge sharpness is the known trade-off - astronomy users report stars blurring in roughly the outer 20% of that huge field
- ✗Heavy for an 8x40 at 30.1 oz - over half a pound more than typical 42mm roof binoculars
- ✗Classic Porro bulk: wide, boxy, and not remotely pocketable or compact around the neck
- ✗Porro prisms are more susceptible to going out of collimation if dropped or knocked - owners advise checking alignment on arrival
- ✗Optics are good but not high-end - no ED glass, so some color fringing appears on high-contrast subjects
- ✗Newer Chinese-made ED roof binoculars at similar prices have eroded its once-unbeatable value position
- ✗16.4 ft close focus is poor for butterflies, dragonflies, or feeder-distance birding
- ✗An aging design in a Nikon lineup that keeps shuffling, so availability and pricing fluctuate
Nikon Aculon A211 10x50 vs Nikon Action EX 8x40: common questions
Is the Nikon Aculon A211 10x50 better than the Action EX 8x40 for stargazing?▾
It has more reach and owners recommend it as a first astronomy binocular, but it needs a tripod because 10x at 31.7 oz shakes. The Action EX's wide field frames big star fields well, though owners report stars blurring in the outer 20% of the view.
Can I use the Nikon Aculon A211 10x50 in the rain like the Action EX 8x40?▾
No. The Aculon is not waterproof or fogproof, and owners warn that rain or a cold-to-warm transition can fog it internally. The Action EX is waterproof and nitrogen purged, which owners cite as the main reason to choose it.
Which is better with glasses, the Nikon Aculon A211 10x50 or the Action EX 8x40?▾
The Action EX by a wide margin. Its 17.2mm of eye relief lets glasses wearers see the full field, while owners call the Aculon's 11.8mm the most common complaint, with a large part of the view lost in glasses.