The Swan eyepieces are super wide angle designs with a 72° apparent field of view. They use simple but sophisticated five-lens optical systems for generally higher contrast than the more complicated optical designs used in some other super wide angle eyepieces that use up to eight lenses. All lenses are fully multicoated for high light transmission. Lens edges and internal field stops are blackened to reduce internal reflections and improve contrast. The eyepiece rubber grip ring is useful for safer handling of the heavier 2" eyepieces in cold weather when wearing gloves. The eyepieces have soft roll down rubber eyecups for eyeglass use. They can be used for all types of observing, with all telescope types, but they are recommended for use with focal ratios up to f/6 and above. Dust caps are provided for both ends of each eyepiece. A soft protective drawstring-equipped velvet storage bag is standard equipment with each.
This 5-element super-wide angle 25mm SWAN EP's panoramic views at 72 deg. FOV will leave you speechless! A premium eyepiece at a fraction of the cost its worth!
Super Wide FOV
Outstanding super-wide field of view: 72 deg. FOV
Fully Multicoated lenses for excellent transmittance.
Reduced chromatic aberration.
Improved contrast compared to similar EPs.
Internally fully blackened (lens edges and internal spacers).
No flaring or ghosting on high-contrast objects.
Light and Easy
Soft rubber eyecup.
Very Long eye-relief: 21mm.
No internal reflections, kidney beaning or other distracting distortions.
Terrific Fit and Finish
High-resistance anodized black barrel.
Smooth design for no hook up in your focuser.
Threaded for use with 2" filters.
Mar 11, 2016
Perfect complement to 40mm eyepiecePros:
Strong Construction,Crisp,Wide Angle,Quality LensesCons: Comments:
I bought the 25mm a few months after my purchase of the Swan 40mm, 2 inch eyepiece. These two eyepieces are my two favorites. I use them while observing deep space objects.
This review was provided courtesy of AgenaAstro.com
Nick Salt New Member
- Skill Level
- Time with Product
Jan 27, 2015
- User Notes:
- Review by Nick of Ontario, Canada.
No problemsPros: Cons: Comments:
I use this on my 10" f/4.7 dobsonian. I find you don't notice the coma unless you are specifically looking for it. Excellent views and one of my most useful eyepieces in my collection. Would definitely recommend to the amateur astronomer on a budget. I'm sure there are better options but for the price you cannot beat it.
This review was provided courtesy of AgenaAstro.comSort by
Apparent Field of View 72° Barrel Size 2" (50.8mm) Bolt Case Included Yes - Free Agena Eyepiece Container Bolt Case Size Agena 65x80mm Coatings Fully Multi-Coated End Caps 2 Eye Relief by Design 21mm Filter Threads Standard 2" Filter Thread (M48 x 0.75) Focal Length 25mm Lens Elements 5 Lens Groups 3 Parfocal Yes Blackened Lens Edges Yes Manufacturer William Optics Eyepiece Focal Length 20.1mm - 30mm Eyepiece Field of View 71 - 80 degrees Eyepiece Series William Optics SWAN Barrel Type Tapered barrel Eyepiece Weight 11.64oz (330g)