With a true flat field and two high quality ED glass elements of different glass types, the new Agena StarGuider Dual ED eyepieces are characterized by a significantly high contrast image. These 1.25" fully multicoated (FMC) eyepieces give maximum detail and definition across the entire 60 degree field of view (FOV). This feature is especially useful for telescopes without tracking capability where the object drifts across the field of view during observation. A great value, these eyepieces are exceptional at nearly eliminating lateral color aberration and light scatter often associated with more expensive eyepieces that are better suited for deep space objects.
The eyepieces are parfocal, minimizing the amount of refocusing needed when switching from eyepiece to eyepiece within the series.
Agena Dual ED Eyepieces vs. More Expensive Eyepieces:
Premium (and costly!) eyepieces that have similar wide fields of view need many exotic glass elements to achieve that wide field of view - as many as 9 lenses or more. More lenses mean more cost and more glass, which attenuates the amount of light you see. That also means there are more air-to-glass surfaces that can scatter light - reducing contrast and sometimes causing multiple reflections (ghosting) when viewing very bright objects such as the Moon and planets. Extra lenses can also mean compromises in the overall design that can often lead to other issues.
One such issue of all that glass is lateral color aberration. This results when different wavelengths (colors) of light pass through the eyepieces focal plane at different points and appear as a cloud of false color around bright objects. Another issue is light scatter seen as a distracting halo or glow around bright objects. This can also reduce contrast. Light scatter and lateral color are rarely seen in very wide field eyepieces when observing faint deep sky objects, but they become very apparent when viewing lunar, planetary, and double star objects. These objects don't need an extra-wide field of view to see small details and subtle contrast differences. Our 60 degree eyepieces provide high contrast, no scattered light, and the highest possible definition.
Agena Eyepieces - Rooted in Solid Design:
Orthoscopic and Plossl eyepieces have traditionally been the designs of choice for lunar, planetary, and binary star/star cluster observations. Their low number of lenses (typically four) and air-to-glass surfaces give better contrast and definition than the more exotic extra wide field eyepieces. A high quality orthoscopic or Plossl eyepiece on a good telescope gives views of Mars, Jupiter, and Saturn that can be breathtaking. But even these designs can be improved upon for lunar and planetary use.
Long Eye Relief - Up To 20mm!
Agena's StarGuider Dual ED eyepieces are the first long eye relief eyepieces with a comfortably wide field for planetary observing that also give the sharpness, contrast, and lack of lateral color and light scatter of the best orthoscopic and Plossl designs. What they don't have is the limited eye relief and restricted fields. Our eyepiece eye relief averages around 18mm and is as much as 20mm in the 25mm focal length model. Even the 5mm eyepiece has almost 16mm of eye relief! Experienced observers will truly appreciate such generous eye relief at significant magnifications.
The nicely machined body is rubberized and scalloped grooves around the circumference at the top provide a secure grip in all conditions.
Sharpness, Great Contrast and Flat Field of View:
With up to six lens elements in this unique design, these eyepieces are fully internally baffled and all internal spacers have antireflection microbaffles on their edges with flat black anodizing to reduce reflections. The field stop also has microbaffles in its edge to reduce off-axis flaring and produce a sharply delineated field edge. Every air to glass surface is broadband multicoated for peak light transmission and outstanding contrast on subtle lunar and planetary detail. The lens edges are blackened to eliminate internal reflections.
The eyepieces have a twist-up eyecup that can be raised or lowered as much as 11mm to provide the eye relief you find most comfortable. Spherical aberration of the exit pupil is well controlled, so there are no serious blackouts or kidney-bean effects if you move your eye slightly off the axis. Dust covers are provided for both ends of each eyepiece. A groove is machined into the nose piece barrel to ensure the eyepiece is less likely to fall out of the diagonal or focuser if the capture screw becomes accidentally loose.
- Focal length: Available in focal lengths of 5mm, 8mm, 12mm, 15mm, 18mm and 25mm
- 1.25" with filter thread
- Field of view: 60°
- Fully multi-coated on each glass/air surface
Jul 17, 2018
Nice eyepiece, but better than 5mm TMB Planetary II??Pros: Cons: Comments:
After doing a lot of research, I bought this eyepiece to see if it was going to be the "one-two knockout punch" for my longtime and well-used 5mm TMB PLanetary II eyepiece.
Overall, construction of the Starguider looks and feels very solid. Weight is on par with eyepieces of a similar design and the 60 degree AFOV is helpful if your telescope isn't equipped with a tracking motor. This is the only Starguider eyepiece I own and it is not parfocal with any other eyepieces in my case, so be prepared to re-focus after inserting it into the diagonal. Lense surfaces have uniform green coatings and, while the design is very pleasing, I have to say that I'm not a fan of the "twist-up" eyecup. To each his own...
The 5mm has good eye relief and a fairly dark background. Scatter is kept to a minimum, focus is very good when using a prism diagonal, and images stay sharp across the entire field. When seeing becomes steady, Jupiters's northern and southern equatorial bands become crisp and well-defined, as do the darker polar regions. There is no detectable false color when viewing Jupiter or the Moon.
All in all, the Starguider is a very capable planetary eyepiece, but is it better than the 5mm TMB Planetary II? Based on my own tests and observations, I would have to say the answer is "No". While the Starguider has a much sleeker design, optical quality is a draw between the two eyepieces. In my honest opinion, both eyepieces are equally strong and capable for planetary work.
That being said, if you're looking for your first hi-power planetary eyepiece, that won't break the bank and provides you with nice views, give the Starguider a try. I doubt that you'll be disappointed. Clear Skies!!
This review was provided courtesy of AgenaAstro.comJan 24, 2018
Really like these!Pros: Cons: Comments:
I bought this to go with my Christmas scope, a 102mm f/7. It gives me around x142 and that's about the max for my red zone seeing. It has given me great views of Jupiter and split a couple of cools doubles.
I am no eyepiece expert, but this is my second Duel ED and I am very happy with it in my new APO.
This review was provided courtesy of AgenaAstro.com
Ronald Zincone New Member
- Skill Level
- Time with Product
Jan 5, 2017
- User Notes:
- Review by Ronnie Z.
Crazy good for the pricePros: Cons: Comments:
I purchased this and the 3.5 mm version to use with a 71mm f5.6 refractor that I use as a rich field finder on my Dob and as a grab and go planetary scope. They are absurdly good for the price. I see no false color on the moon and Venus and they are sharp across the 60 degree field. I see no field curvature with these as I had with Naglers.
This review was provided courtesy of AgenaAstro.comNov 11, 2016
Best Eyepieces Series for the MoneyPros:
Accurate,Compact,Quality Lenses,Strong Construction,Easy to UseCons: Comments:
The 5mm Agena 1.25" Starguider Dual ED Eyepiece is one of three of the Starguider line I have. I find the performance of this eyepiece to be amazing, especially considering the price. It's sharp across the field and shows no noticeable aberrations. The field of view is not the largest available in eyepieces, but I find it to be just right, wide, but not overly so. Eye relief is excellent in all focal lengths, including the 5mm and eye position isn't super critical, resulting in a very comfortable viewing experience. Scatter is very low, compared to some higher end eyepieces. What really sets this eyepiece apart from others is the exceptional color dynamic seen on planets, especially Jupiter. Colors are not harsh and not faded. The dual ED elements are evidentially making a difference compared to other brands I've used. In my opinion, especially considering the price, they are outstanding eyepieces.
This review was provided courtesy of AgenaAstro.comSep 29, 2016
Easy to Use,Quality Lenses,Strong ConstructionCons: Comments:
I bought this for my wife's telescope, which I got her for Christmas last year. This really helped us be able to see the stars and planets better. I got some great pictures of Mars and the moon. Thanks so much!
This review was provided courtesy of AgenaAstro.comMay 13, 2015
Quality Lenses,Strong ConstructionCons: Comments:
I like this eyepiece. It gets really close to Jupiter. The field looks in focus from edge to edge. That's important to me because at 240x with an unguided scope, it only takes about 45 seconds for an object to cross! I have only had this out one night so far. Could see Great Red Spot and 4 bands on Jupe. I have a 8mm TeleVue that will get a lot LESS use now that I have this. Eye relief is important! (8inch f6 Skywatcher collapsible Dob)
This review was provided courtesy of AgenaAstro.comSort by
Apparent Field of View 60° Barrel Size 1.25" (31.7mm) Bolt Case Included Yes - Free Agena Eyepiece Container Bolt Case Size Agena 52x80mm Coatings Fully Multi-Coated End Caps 2 Eye Relief by Design 15.8mm Filter Threads Standard 1.25" Filter Thread (M28.5 x 0.6) Focal Length 5mm Lens Elements 5 Lens Groups 3 Rubber Eye Guard Yes (Twist-Up Eyecup) Blackened Lens Edges Yes Manufacturer Agena AstroProducts Eyepiece Focal Length 5mm and Under Eyepiece Field of View 51 - 60 degrees Eyepiece Series Agena Dual ED Barrel Type With safety undercut Eyepiece Weight 6.80oz (192.78g)