The eyepiece is half the optics - and every telescope is only as good as its weakest link. That is why Baader Planetarium not only offers high-quality star diagonal mirrors and prisms (which we present in this PDF), but also several series of eyepieces. Each has its own special features, which we would like to present to you briefly here. Besides, they are firmly integrated into the Baader accessories programme and offer interesting solutions for eyepiece projection and binocular observation.
The series at a glance
||6 / 10 / 18 / 32||31 / 36||5 / 8 / 10 / 13 / 17 / 21 / 24||8-24 (with Barlow 3,6-10,7)||4,5 / 6,5 / 9 / 12,5 / 14 / 17,5|
|Nosepiece||1,25"||1,25"+ 2"||1,25"+ 2"||various threads1,25" + 2"||25" + 2"|
The most favourable - or better, most inexpensive - eyepiece series are the Classic Ortho/Plössl eyepieces, which are available individually or in a set with an eyepiece turret and a Barlow lens. This complete set was deliberately created as an alternative to the usual eyepiece cases, so that beginners also receive a high-quality and well thought-out set right from the start. There are no pointless accessories here that drive up the price and yet are hardly used.
The series consists of a
- Classic Plössl 32mm, 1¼" Eyepiece (HT-mc) - w.aux spacer tube and winged rubber eyecup (#2954132 , € 68,-) ,
- three orthoscopic eyepieces:
- as well as a Baader Q-Barlow 1.3x/ 2.25x (#2956185 , € 55,-) (extension factor varies depending on configuration).
The eyepiece set thus covers all magnifications that are useful on telescopes with 1.25" eyepiece clamps:
- The 32mm Plössl offers the largest possible true field of view that fits into a 1.25" eyepiece clamps. Longer focal lengths would provide a brighter image, but not a larger field of view - but instead the famous, unpleasant "tunnel vision". The 50° of the 32mm Plössl allows comfortable observation.
- Orthoscopic eyepieces are still the first choice of planetary observers today, as they achieve the highest sharpness in the centre of the image. The small number of lenses together with modern coating ensures a bright, high-contrast image even at the highest magnification.
- The barlow lens provides two magnification factors: 2.25x in the standard configuration, and alternatively 1.3x when the barlow element is screwed directly into the eyepiece just like a filter. This makes it suitable not only for many modern planetary cameras, but also for the Q-Turret eyepiece revolver, on which it again delivers 2.25x.
- The Baader Q-Turret Eyepiece Set (eyepiece revolver, 3x Classic Ortho, 1x Classic Plössl, 1x Q-Barlow 2.25x) (#2957000, € 280,-) practically turns the eyepiece set into a zoom eyepiece with the uncompromising optical quality of fixed focal length eyepieces. It works on Schmidt-Cassegrains and refractors as well as Newtonian telescopes with around 40mm backfocus - which often corresponds roughly to the light path that the extension tube of many Newtons has for visual operation, and which is otherwise only removed for DSLR photography.
The eyepiece design is tried and tested, but not outdated: Since only a few lenses are used, a very bright, clear image is possible. Contemporary adaptations increase observing comfort: with the Plössl, with its large interpupillary distance, a removable extension helps to find and hold the view - whether with glasses or without. The foldable rubber eyecup protects against stray light as well as scratches on the glasses, and the conical upper end of the orthoscopic eyepieces allows a comfortable view. As a special feature, the orthos have an unusually large field of view of 52° for this design - significantly more than classic orthos, so they are also fun for deep-sky observing!
The Classic eyepieces are the ideal choice for quality-conscious beginners and price-conscious professionals alike, for whom image quality is more important than a huge field of view! They offer the sharpness and contrast that are important for planetary observation, along with a larger field of view than usual.
Technical data on the Classic Orthos can be found here: PDF with technical data
The eye lens of the Orthos is "free" so that the eye can be placed close to the eyepiece and at the same time there is enough space for the eyelashes.
The Hyperion® eyepieces
The Hyperion® eyepieces are the all-rounders among our eyepieces: With a field of view of around 68°, the edge of the image field is no longer a problem with these wide-angle eyepieces. They also offer more configuration options than typical wide-angle eyepieces - up to and including focal length fine-tuning and photography.
Three eyepiece types belong to this series:
- The 72° Baader 31mm Hyperion Aspheric 2" Eyepiece (#2454631 , € 195,- € 156,-) and Baader 36mm Hyperion Aspheric 2" Eyepiece (#2454636 , € 205,- € 164,-)
- The modular 68° Hyperion® eyeoieces with focal lengths from 5-24 mm
- The Baader Hyperion Universal Zoom Mark IV, 8-24mm eyepiece (1¼" / 2") (#2454826 , € 275,- € 220,-)
All Hyperion® eyepieces have the good-natured viewing characteristica and the possibility of camera adaptation in common.
Photography enthusiasts can adapt a camera body to the eyepiece light-proof and without tilting.
The two 31mm and 36mm Aspheric eyepieces (
Baader 31mm Hyperion Aspheric 2" Eyepiece (#2454631, € 195,-)
Baader 36mm Hyperion Aspheric 2" Eyepiece (#2454636, € 205,-)
) are lightweight and compact 2" eyepieces for lower magnifications and large fields of view that eliminate many of the aberrations of simpler wide-angle eyepieces at once with their aspheric lens design: Sharpness is achieved over the entire field of view and distortion is reduced to a minimum.
Although these are true 2" eyepieces, as a special feature the 2" nose piece can be replaced by a 1.25" nose piece. This way, the eyepiece can also be used on smaller telescopes and offers a larger field of view than usually possible, as the field stop is far behind the bottleneck of the 1.25" socket. This trick was also used with the Eudiascopic eyepieces from Baader. But be careful: Inexpensive telescopes often come with Amici prisms that have even less free aperture - with a Hyperion® you can only see how much power these undersized prisms swallow up!
Wide angle on a binocular: The Aspheric eyepieces also fit on a bino-viewer with the 1.25" nose piece.
The modular 68°-Hyperion® eyepieces have a dual body: they can be used as 1.25" as well as 2" eyepieces. There is no change in optical performance, you have the free choice - at these focal lengths, 2" are optically unnecessary, but offer better hold and may save you an adapter. As a bonus, the inexpensive 1.25" filters are sufficient; if you have 2" filters, simply use the 2" filter thread, which most reducers to 1.25" have anyway.
An interesting feature of the modular Hyperion® eyepieces (from 5 to 21 mm) is their separable housing: the 1.25" nosepiece with the optical element integrated in it can be removed. You can then either use only the upper half and have an eyepiece with around 30 mm focal length (depending on the model - although a real 30 mm eyepiece will provide a better image) - or you can insert a Hyperion® Finetuning Ring or a 2" filter cell (with or without filter) before reattaching the 1.25" nosepiece: This way you shorten the focal length (similar to a zoom eyepiece) and can bring the eyepiece to the focal length you still lack. For example, if you are looking for a very short focal length wide-angle eyepiece with 2.6 mm focal length, you can combine the 5 mm Hyperion® with the 14 mm and the 28 mm finetuning ring. The comfortable viewing of the eyepiece and its imaging properties are maintained! Only in the case of the 24 mm eyepiece (as with the two Aspheric) there is no optic in the 1.25" nosepiece, here it serves only as a purely mechanical 1.25" adaption - all other eyepieces can be adapted.
The Baader Hyperion Universal Zoom Mark IV, 8-24mm eyepiece (1¼" / 2") (#2454826, € 275,-) covers the focal length range of 8-24 mm. Especially important: Unlike many other zoom eyepieces, the field of view is also largest at the highest magnification, instead of getting smaller and smaller. So you don't just see a small section of the image at the highest magnification! At the same time, it is our most versatile eyepiece: Not only does it fit any telescope, but also many spotting scopes from Celestron, Kowa, Zeiss and many other manufacturers, even those with screw threads!
Common to all Hyperion® eyepieces is their suitability for eyepiece projection or digiscoping - via the integrated M43 and SP-54 threads you can connect cameras with or without lenses and thus take photographs through the eyepiece. We have summarised more about this in a separate article: the camera at the eyepiece, as well as in this PDF: Digiscoping - camera adaptations for afocal photography and eyepiece projection.
Conclusion: The Hyperion are ideal for anyone looking for good all-round eyepieces with good value for money. The gain in field of view and observing comfort compared to standard accessory eyepieces is impressive.
Technical data on the Hyperion® eyepieces can be found here: PDF with technical data
Morpheus® – uncompromising wide-angle quality
The latest addition to the Baader eyepieces are the Morpheus, whose optical design incorporates the latest experience and developments. The spacewalk feeling - the feeling of diving into the universe without being constricted by the edge of the field of view - is achieved by the generous eye relief of around 20mm, the large eye lens and the 76° field of view. Instead of artificially inflating the field of view to 100° or more, emphasis was placed on an extremely sharp field of view without noticeable distortion. For planetary observation in the centre of the image, the Morpheus® rivals our best ever Zeiss Abbe Ortho (ZAO) I and II eyepieces in sharpness and contrast, but offers a much larger field of view. When a "crisp" Jupiter hovers among the stars at high magnification, it's an impressive sight - and even more so in bino-viewer! The Morpheus® combine the imaging qualities of planetary eyepieces with the observing feel of wide-angle eyepieces. A dream of an eyepiece!
Thanks to the large eye lenses, the image is easy to find even for beginners - this is not only important for public observations, e.g. at public observatories, but also guarantees a relaxed view for experienced observers. A new approach has been taken with the foldable eyecup, which has been improved once again compared to the first production series. The round, soft eyecup hugs the eye and can be folded down for spectacle wearers; those who want it more stable can screw in the supplied M43 metal extension. And especially for use with a bino-viewer, a winged eyecup is included that provides effective protection from stray light. So you can adapt the eyepiece to your needs!
While the inner values are convincing at first glance, understatement reigns when it comes to the body: instead of making an impression with sheer size, a body as slim as possible and yet as stable as possible was created from hard aluminium. It is light and slim, ideal for use with a bino-viewer. A rubber coating ensures a good grip, and the combined 1.25"/2" nosepiece is fitted with safety kerfs. These many small grooves provide a better grip in the focuser. The classic safety groove has fallen out of favour with many observers, and rightly so, because it is often designed too deep or positioned so awkwardly that the clamping mechanism of the focuser causes it to tilt. The safety kerfs circumvent this problem and ensure a secure hold, even when a camera is connected via the M43 connection thread. Cameras with M43 threads (e.g. Panasonic and Sony) can be connected directly via the M43 extension provided, without the lenses of the objective and eyepiece touching each other. An adapter to the T-2 system ( Hyperion / Morpheus® T-Adapter M43i/T-2a (M42x0.75) (#2958080 , € 19,-) ) can also be connected for eyepiece projection.
The image plane is directly at the transition to the 1.25" nosepiece. This makes the eyepieces suitable for all devices with a tight focus position - for spotting scopes with 1.25" connection as well as for long-building H-alpha filters. Only with the 17.5 mm eyepiece is the field stop slightly lower in the housing, but it still works perfectly on most spotting scopes.
The Morpheus® eyepieces are also the eyepieces with the most comprehensive accessories. The pouches, which also function as belt holsters, were born out of practical experience: This way you always have the eyepieces at hand if there is no storage space available, and you have them protected from the wind under your jacket on your warm body - a good remedy against dew! A small clip can also be attached to the belt holster so that you can blindly feel which eyepiece is in the bag. If the eyepieces have been in the light for some time, the labelling will glow for a longer period of time so that you can see which focal length you have in front of you without a torch.
The Morpheus® eyepieces rival our best Zeiss-Ortho eyepieces for planetary viewing. At the same time, they offer the longed-for spacewalk feeling without distorting the image. In price, they are only slightly above simpler wide-angle eyepieces - in image, far above.
Technical data on the Morpheus® eyepieces can be found here: PDF with technical data
Accessories for eyepieces
Of course, the eyepieces from Baader Planetarium are ready for immediate use. However, depending on the intended use, there are interesting accessories that should be briefly mentioned here.
The right eyecup is very important for observing comfort. This is especially true for observers without glasses, as it keeps the eye in the correct position and distance above the eyepiece. In binocular observation, a winged eyecup protects against stray light from the side - these eyecups are also available for other eyepiece diameters. Observers with glasses can simply fold down the eyecup and thus protect the expensive lenses from scratches by the metal housing of the eyepiece.
Various eyecups can be attached to the M43 thread of the Hyperion® and Morpheus® eyepieces. The Rubber/Metal foldable Morpheus® eyecup (M43-threaded) (#2454655 , € 16,-) (which comes as standard with the Morpheus® eyepieces) even has a thread for screwing onto the Hyperion® and Morpheus® eyepieces - so it cannot get lost. With the Hyperion / Morpheus® M43 extension (#2954250 , € 20,-) (which is also included with the Morpheus®), there is a robust metal sleeve that can be screwed between the eyepiece and eyecup to allow for a longer eye relief.
- Rubber/Metal foldable Morpheus® eyecup (M43-threaded) (#2454655 , € 16,-)
- Baader Classic W Rubber Eyecap with folding wing (#2454652 , € 10,-)
- Baader Rubber Eyeshield II for Diameter 33.5 - 34 mm (#2402020 , € 13,-)
- Baader Rubber Eyeshield IV (smooth inside) for Diameter 40,5 – 41,5 mm (#2402030A , € 15,-)
- Baader winged rubber-eyecup 42/43 (Hyperion 68°) (#2454653 , € 14,-)
- Baader winged rubber-eyecup 43/44 (for all Hyperion Zoom eyepieces) (#2454654 , € 14,-)
- Baader Hyperion M43 rubber thread cover and eyeshield (#2454651 , € 8,-)
Nosepiece extensions and adjusting rings
The eyepiece nosepieces can be extended if necessary. This allows you to make all your eyepieces parfocal and saves you refocusing when you switch between different eyepiece designs.
Especially with eyepieces with a combined 1.25" and 2" nosepiece, the focus position differs significantly depending on the adapter used. It can be more convenient here to use the 1.25" nosepiece - or to expand it to 2" with the Baader Pushfix Reducer 2" to 1¼" (T-2 part #15a) (#2408151, € 52,-) as well. The Pushfix has its own stop on its top edge. If necessary, you can also set the eyepiece stop with the Baader Hyperion 2" Finetuning Stopring with brass clamping ring & 2 thumb screws (#2958027 , € 24,-) .
The 2" adjustment ring is also helpful if you are using a 2" prism and need to make sure that the eyepiece (or screwed-on filters) do not hit the prism under any circumstances. This risk does not exist with mirrors and 1.25" prisms.
Homofocality is only convenient for visual observation, for photography it is almost essential: planetary cameras have a small field of view and usually a different focus position than your eyepieces. If the image is too blurred, the planet is often not even visible on the camera image after switching from eyepiece to camera, and it is hard to find. If you set a simple eyepiece to the identical focus position as the camera, centring the planet on the camera becomes child's play. To do this, you need the Stop Ring 1¼" (T-2 part #30) (#1905131 , € 29,-) and probably the Baader 1¼" - 31.8mm nosepiece extension with 1¼" filter thread on both sides (T-2 part #05) (#1905130 , € 19,-) , which is simply screwed into the filter thread of the eyepiece.
When choosing eyepieces for fast telescopes (like f/4), people often ask how well an eyepiece works with them. The question is not actually how well the eyepiece works, but whether it compensates for the errors of a simple mirror such as coma and field curvature. To do this, an eyepiece would have to have a built-in coma corrector - which would introduce new image errors on telescopes without comas such as refractors and Schmidt-Cassegrains or slow Newtons. Moreover, this corrector would then have to be built into every eyepiece, which would unnecessarily drive up the price.
It therefore makes much more sense to leave the coma corrector in the focuser and equip it with an eyepiece clamp. This is the way to go with the 2" MPCC V-1 Mark III Newton Coma Correktor - SET: Visual and Photographic Version (#2458403, € 225,-) . It is just as suitable for cameras as for eyepieces; practically all 1.25" eyepieces can be used at the correct distance via the adapters supplied. Small differences can be corrected via the focusable eyepiece clamp. Many 2" eyepieces can also be used; then the MPCC is screwed into the filter thread of the eyepiece. The correct distances for the Baader eyepieces can be found in the MPCC manual.
The special suitability for photography through the eyepiece is a feature of Baader eyepieces. You can find more on this extensive topic in a separate blog: The camera at the eyepieces
About the author: Alexander Kerste
Alex is a studied biologist and works as a freelancer as an author, consultant and translator. After his studies and the publication of the Kosmos Starchart-Set in 2004, he was a regular freelancer for Astronomie Heute and the yearbook Der Himmel for the Spektrum-Verlag in Heidelberg. He is in charge of the Beginner courses on www.Astronomie.de and is a voluntary active member in the Robert-Mayer-Observatory since 1993. Since then, he has published a number of books on Celestron-Telescopes as well as Digiscoping and Astrophotography. One of his books on Astronomy with binoculars is also freely available at freebook.fernglasastronomie.de. In addition he supervises the Northern lights and star tours from Hurtigrute – these were also published in a travel guide, further articles can also be found on his blog kerste.de.