The **Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece** and What It Taught Me
The Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece is a specialized optical instrument designed for serious astronomical observation. It promises an expansive 100-degree field of view and robust construction features like nitrogen purging and waterproofing. My journey to this particular eyepiece began with a desire to push the boundaries of my visual astronomy experience, specifically when observing deep-sky objects. While my existing eyepieces offered decent views, I found myself wanting that immersive, “stepping into the universe” feeling that only a truly wide field can provide. I briefly considered other high-field-of-view eyepieces from brands like Tele Vue and Meade, but the specific combination of features here, particularly the nitrogen purging, piqued my interest. My initial impression upon unboxing was one of solid engineering; it feels substantial, well-machined, and built to last.
Real-World Testing: Putting **Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece** to the Test
First Use Experience
My initial testing of this Explore Scientific optic took place under the clear, dark skies of a rural observatory site. I mounted it onto my 10-inch Dobsonian telescope, eager to see how that claimed 100-degree field of view translated into actual observing. The eyepiece felt substantial and reassuringly solid when I first inserted it into the focuser. Performance was immediately impressive, offering an incredibly immersive view of the Andromeda Galaxy, allowing me to take in its full sweep without needing to constantly pan.
Over the following weeks, I continued to test this unit in various conditions, including nights with a touch of dew and a faint breeze, where its waterproof and nitrogen-purged design were a definite plus. The 2-inch barrel fit snugly and securely in my telescope’s focuser, and the 20mm focal length provided a magnification that was perfect for many nebula and galaxy targets. The wide apparent field of view meant fewer eyepiece changes, allowing for longer, more uninterrupted observing sessions.
Extended Use & Reliability
After several months of regular use, this eyepiece has proven itself to be a reliable workhorse. It has accompanied me on numerous star parties and solo observing nights, enduring the typical wear and tear of being handled and moved. I’ve noticed no degradation in optical quality, and the internal optics remain perfectly clear, a testament to the nitrogen-purged internals preventing any moisture ingress.
Cleaning has been straightforward; a gentle blast of air and a careful wipe with a microfiber cloth are usually sufficient. The robust construction has withstood accidental bumps against my telescope’s tube without issue, and the heavy-duty housing shows no signs of significant scuffing or damage. Compared to some older, less robust eyepieces I’ve owned, this Explore Scientific model feels significantly more durable and less prone to long-term wear.
Breaking Down the Features of **Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece**
Specifications
The Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece boasts a focal length of 20mm, which, when paired with common telescope focal ratios, provides a moderate magnification ideal for wide-field viewing. Its impressive 100-degree apparent field of view is a key specification, offering an expansive vista that truly draws you into the cosmos. The eyepiece measures 156mm in length and 70mm in width, contributing to its substantial feel and the generous internal optical path.
Weighing in at 38.1oz (968g), this optic is decidedly on the heavier side, a common characteristic of high-performance, multi-element wide-field designs. Its 2.00″ barrel size ensures compatibility with modern telescope focusers, and the 14.5mm of eye relief is adequate for comfortable viewing, though perhaps not generous for those who wear eyeglasses. The field stop diameter of 34.8mm is substantial, directly correlating with the impressive 100-degree field of view it delivers.
Performance & Functionality
The primary function of this eyepiece – delivering a wide, immersive view – is executed exceptionally well. The 100-degree field of view is truly breathtaking, making objects like the Orion Nebula appear vast and detailed, with stars extending right to the edge of your vision. Optical performance is sharp and clear across the field, with minimal chromatic aberration, even on bright objects.
However, the substantial weight can be a consideration for some telescope mounts, potentially requiring counterweights. While the 14.5mm of eye relief is functional, users who require more space between their eye and the lens may find it slightly tight. The nitrogen-purged design is a significant advantage, providing peace of mind against internal fogging, especially in humid or fluctuating temperature conditions.
Design & Ergonomics
The build quality of this Explore Scientific eyepiece is immediately apparent. The anodized aluminum housing feels incredibly robust, with a fine, matte finish that resists fingerprints and glare. The rubberized eyecup is adjustable and provides a comfortable resting point for the eye, though its firmness might be a point of contention for some.
Ergonomically, the sheer size and weight mean it’s not an eyepiece you’ll forget is there, but the large 2-inch barrel offers a good purchase for insertion and removal. The focus travel required to bring objects into sharp view is smooth and consistent, with no hint of looseness or grinding. Its overall design speaks to a product built for serious, long-term use in demanding observing environments.
Durability & Maintenance
Given its waterproof and nitrogen-purged construction, this eyepiece is designed for longevity. The sealed internals are a significant boon, protecting the delicate optical coatings from moisture and dust that can degrade performance over time. I’ve experienced no issues with fogging or internal dust accumulation, even when moving from a warm room to a cool night sky.
Maintenance is straightforward; regular cleaning with appropriate optical cleaning tools will keep the external surfaces pristine. The robust build suggests it can withstand the occasional minor drop or bump, although extreme impacts should naturally be avoided. There are no obvious weak points; it feels like a solid, well-engineered piece of equipment designed to last for many years.
Accessories and Customization Options
The Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece comes with essential accessories to protect it during storage and transit. It includes a sturdy, padded carrying case that provides excellent protection against bumps and scratches. Also included are protective lens caps for both the eyepiece end and the barrel end, ensuring the optics are shielded when not in use.
While there are no direct customization options for the eyepiece itself, its 2-inch barrel allows for compatibility with various filter systems. Astronomers can readily attach 2-inch astronomical filters such as nebula filters or light pollution filters to enhance specific observing targets. This compatibility with standard accessories is a significant advantage, allowing users to tailor their viewing experience.
Pros and Cons of **Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece**
Pros
- Breathtaking 100-degree apparent field of view provides unparalleled immersion.
- Nitrogen-purged internals and waterproof construction ensure longevity and prevent fogging.
- Excellent optical performance with sharp, clear views and minimal aberrations.
- Robust, heavy-duty construction feels built to withstand rigorous use.
- Wide 2-inch barrel offers compatibility with standard filters and focusers.
Cons
- Significant weight (38.1oz / 968g) can be a burden for smaller or less robust mounts.
- 14.5mm of eye relief may be insufficient for eyeglass wearers or those preferring more distance.
- The premium price point places it out of reach for budget-conscious beginners.
Who Should Buy **Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece**?
This particular eyepiece is ideally suited for experienced amateur astronomers who are serious about deep-sky observing. It’s a fantastic choice for those who own larger aperture telescopes (8 inches and above) and are looking to maximize their viewing experience with an expansive, high-quality field of view. Visual observers who prioritize immersion and detail in nebulae, galaxies, and star clusters will find this optic highly rewarding.
Conversely, beginners or those with smaller, less stable mounts might want to consider lighter, less wide-field options. Individuals who wear eyeglasses or require substantial eye relief might also want to look elsewhere for a more forgiving design. If you’re on a tight budget or prioritize portability above all else, this high-performance unit might not be the best fit. A good 2-inch filter set would be a highly recommended complementary purchase to enhance its capabilities.
Conclusion on **Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece**
The Explore Scientific 20mm 100 Degree Series Nitrogen-Purged Waterproof Eyepiece is a premium instrument that delivers an exceptional visual astronomy experience. Its massive field of view and excellent optical quality make it a standout performer for observing deep-sky objects. The robust build, combined with waterproof and nitrogen-purged features, ensures it’s a durable and reliable tool for years to come.
While its substantial price tag and considerable weight are notable factors, the performance and features justify the investment for dedicated enthusiasts. For the serious visual astronomer seeking the ultimate immersive view of the cosmos, this eyepiece is an easy recommendation. If your telescope can handle its weight and you crave that expansive, detailed vista of the universe, it’s an addition that will not disappoint.