Explore Scientific 14mm 100º Eyepiece - 2"

Explore Scientific 14mm 100º Eyepiece - 2"
Item # ES-EPWP10014-01
  • The Explore Scientific 14mm 100 Eyepiece has been getting lots of thumbs up from seasoned amateur astronomers and now you can have one of your very own for a great price!
  • The eyepiece is waterproof and Argon-purged, and it comes with a replaceable soft, folding eyecup.
  • Eye relief on the Explore Scientific 14mm 100 Eyepiece is 14.5mm, the barrel is 2" and accepts 2" filters.


Explore Scientific 14mm 100º Eyepiece

The development of the Explore Scientific 14mm 100° Series Argon-Purged Waterproof Eyepiece was a collaborative effort of astronomers and engineers who tested our prototypes again and again, in the field and in the factory to make refinements to produce the final production eyepiece.

Inspiration for ultra-wide field eyepiece designs came from several designers. Wright H. Scidmore patented important ultra-wide angle eyepiece designs (one with long eye-relief) in the ‘60s for the U.S. government. His influence can be seen in many eyepiece designs on the market today with eyepieces of 68 to 80 degrees apparent field and more. Carl Zeiss made eyepieces of 110 and 120 degrees apparent field for use in U-boat periscopes before World War II. These are but two notable designers who developed ultra-wide field eyepieces over the decades.

Like all Explore Scientific eyepieces, the lens elements of the 100° eyepiece are meticulously cleaned and aligned before being installed in their precision machined lens barrels.

Each lens and lens grouping have EMD (Enhanced Multilayer Deposition) Coatings and are edge-blackened to eliminate light scatter and maintain image contrast.

Contrast is further enhanced with baffles that mask and deflect unwanted stray light.

These eyepieces with their huge apparent field of view not only gave the observer a panoramic visual experience, but they relax the eye so the observer could pay attention to subtle details for extended periods. These ultra-wide angle eyepieces played a critical role in the military for aiming at targets, and their long eye-relief counterparts helped reduce eye injury from recoil.

To make sure, every 100° eyepiece is tested by submerging them down to 1 meter of water for 30 minutes.

Years later such eyepiece designs transformed the visual experience for amateur astronomers, as they started using military surplus cannon sight eyepieces on their backyard telescopes. Al Nagler with his company Tele Vue introduced his Nagler 82 Degree eyepieces (and later introduced the 100 degree Ethos eyepieces), and then other commercial telescope companies such as Meade Instruments, Pentax, Celestron, and others made ultra-wide field eyepieces specifically for use in amateur telescopes. Since extreme performance eyepieces are expensive to make, they come with a relatively high price tag over standard eyepieces.

After announcing Explore Scientific’s line of telescopes at the Astronomical League Conference in the summer of 2008, we decided to focus on extreme performance, ultra-wide angle eyepiece designs as well. We wanted to offer ultra-wide angle designs in popular formats at lower prices. Now more astronomers could experience the benefits of the amazing panoramic views these eyepieces provide.

Each and every Explore Scientific eyepiece is inspected both at the factory and again at our USA facility in California.

Here we are making final visual and cosmetic inspections where we check for assembly integrity, cleanliness, and optical performance (including a test for visual image edge consistency) before shipping them to our customers.

Developing our new eyepieces we wanted to take a fresh perspective and address several points. Our goal was to produce an ultra-wide angle design that provides pride of ownership at a great value:

Focus on Value - We invite direct comparison to any eyepieces on the market in their category.

Protection from the Outdoors - By making the eyepiece body Argon-purged and waterproof eyepiece internal elements will remain as pristine as the day they were assembled. The sealed, dry environment is impervious to internal fogging and contaminants such as fungus growing in between the lens elements. Our waterproof eyepiece is easier to clean, and there is no risk of cleaning solution migrating from the top of the lens and seeping around edges to be trapped in between elements. To insure a perfect seal we test every eyepiece in one meter of water for 30 minutes.

Creating an Identity - We look at purchasing fine optical equipment as an investment, and it should be treated as such. With a unique serial number on each eyepiece we can track when a product was made, and the owner can document their equipment for insurance and warranty purposes.

Explore Scientific 14mm 100º Eyepiece Specifications


  • AFOV: 100 degrees
  • Eye Relief: 14.5mm
  • Waterproof: Submersible to 1 meter for 30 minutes
  • Coatings: All lens-to-air surfaces are full multi-coated
  • Barrel: 2.0" diameter, tapered barrel-style, accepts 2.0" diameter standard filters
  • Eyecup: Soft rubber folding style; Replaceable
  • Weight: 1lb. 14oz.
  • Explore Scientific Product Number: EP10014

    Additional Information

    Additional Information

    SKU ES-EPWP10014-01
    UPC Code 812257014668
    Manufacturer Explore Scientific
    Optical Design Wide Angle
    Barrel Size 2"
    Warranty Lifetime Warranty
    Eyepiece Field of View - Apparent 100º
    Eyepiece Focal Length 14mm
    Eyepiece Eye Relief 14.5mm
    Eyepiece Manufacturer Series Explore Scientific 100º Waterproof
    Eyepiece Weight 1 lb. 14 oz.
    Field Stop Not supplied by manufacturer
    Number of Lens Elements & Groups Not supplied by manufacturer
    Special Feature None
    Comes with Dust Caps? Yes
    Comes with Eye Guard? Yes

    Customer Reviews 6 item(s)

    A great eyepiece for the money
    I don't have a ton of eyepieces but I have observed with some of the best mass production eyepieces there are. This was my first step into the world of $100+ eyepieces and it was a great choice. The FoV, eye relief and edge to edge sharpness is fantastic. Many in my astronomy club have complimented it as well. I'm going to get the 20mm next, this eyepiece has sold me on sticking with Explore Scientific.
    1= Houston, We Have a Problem & 5= It's Out of This World
    Review by matthew / (Posted on 5/25/2013)
    Great Eyepiece
    It really is comparable to the Ethos line. The only downside is the weight of the EP. It is significantly heavier. Under challenging conditions for an EP (F4.5 and lower) it performs as well as the Ethos. Using a coma corrector, the 14mm ES 100 is very sharp at the edge of field in my 16" F4.5 Dob. It may even be better than my astronomy club's Ethos 13mm. Without a coma corrector it is ok at the edge.
    1= Houston, We Have a Problem & 5= It's Out of This World
    Review by Nate / (Posted on 5/3/2013)
    This eyepiece is a real winner. Excellent sharpness & contrast. Comfortable to use. Edge performance is very good in my f/4.5 Newts (without a coma corrector. The 100 deg field, while not quite perfect at the very edge, really makes you feel like you're there. I'm hooked, and will be getting the 9mm ES 100 deg as soon as I can get the funding in place. There are exactly 4 potential downsides that I can see to this eyepiece: 1 price (which is actually relatively low compared to a similar Ethos, 2 size/weight, 3 eyeglass compatibility (I would only see ~75 degrees with my glasses on, but fortunately my astigmatism is mild enough that I don't need to wear them with the 14mm like I do with my 30mm eyepieces, and 4 after using these, your 80 degree eyepieces that used to seem so amazingly wide will now seem claustrophobic by comparison.
    1= Houston, We Have a Problem & 5= It's Out of This World
    Review by Brett / (Posted on 2/23/2011)
    I love this eyepiece
    I started with the 14mm eyepiece, and love the 9mm too. With my next pay check I will complete the set (20mm. Observing is great when three eyepieces cover 90% of your needs. The view through my 16 Dob is awesome.
    1= Houston, We Have a Problem & 5= It's Out of This World
    Review by Grant / (Posted on 9/1/2010)
    Outstanding Value
    The contrast is excellent, the eye relief comfortable, and the field of view is so wide I instantly fell in love with this EP. With my telescope I only star hop, and after getting used to the wide, high contrast view delivered by this EP I have found that I don’t need to go to my longer focal length EP nearly as often to find things. Stars are bright, sharp, and round all the way to the edge of the field of view (M5 really shows this EP off. In my opinion, this EP is an outstanding value!
    1= Houston, We Have a Problem & 5= It's Out of This World
    Review by Sam / (Posted on 6/3/2010)
    very high cost performance
    we compared this eyepiece with ethos 13mm. Maybe many people are interested in this point. we could not find any big difference from this ES14 in comparing. sharpness is enough in full sight. not dull around the edge. we can recommend this strongly.
    1= Houston, We Have a Problem & 5= It's Out of This World
    Review by totoro / (Posted on 9/19/2009)
    Included Items

    Included Items

    • Explore Scientific 14mm 100º Eyepiece
    Questions & Answers

    Product Questions

    What are the actual dimensions of the eyepiece, i.e., height and width?  Also, how is the eye relief measured?  I have a nice 24mm ES 82 deg. ep. that I believe is marketed as having 18mm of eye relief but the lens is recessed quite far.  Thanks.  
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