Founder Optics 1.25" ALIEN Long Eye-Relief Eyepiece - 5mm
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- ALIEN series eyepieces feature a generous 55° FOV and comfortable 20 mm long eye-relief.
- Bright images, low color aberration, superb sharp, crystal clear and impressive true image.
- 5 mm focal length for tight details of the Moon, planets and compact deep-sky targets.
- Parfocal type, minimal refocus required with other ALIEN eyepiece magnifications.
- Threaded for visual filters, and rubber eye guards for a more comfortable and enhanced experience.
Founder Optics ALIEN Eyepieces: Long Eye-Relief for All Occasions!
The Founder Optics ALIEN eyepiece series packs serious observing power into a sleek, easy-to-use design. With the wide range of eyepiece magnifications, you can guarantee there’s one to suit every visual need—whether the Moon, planets, or tight deep-sky targets. These 7-element eyepieces deliver a noticeably flat and wide 55° field of view (FOV), perfect for soaking up every detail.
Looking for something for high-magnification views of lunar craters, planets or compact deep-sky objects? The ALIEN 5 mm eyepiece boasts a generous 20 mm eye relief. This means you can enjoy the view without pressing your face into the eyepiece. Fully multi-coated, edge-blackened optics serve up max light transmission and knockout contrast, while the pop-down rubber eyeguard shields your eyes from stray light for truly immersive viewing.
Standout Features:
- 5 mm focal length for high-magnification details.
- Putting comfort first with a long eye-relief, generous FOV, and rubber eye guard.
- Parafocal with other magnifications in the ALIEN series.
- Thoughtful features like blackened edges, multi-coatings, tapered barrel, and filter threading.
A Series Packed with Thoughtful Features
Built to last, the CNC-machined body features a secure rubber grip and a tapered nosepiece that helps keep the eyepiece in place, even if the thumbscrew isn’t fully tightened. Weighing just 6.5 oz (184 g) and standing about 4.33 in (110 mm) tall, with the eye guard extended. Compact, comfortable, and ready for any adventure! Plus, the 1.25-inch barrel is threaded for M28.5x0.6 filters, giving you even more ways to enhance your views.
Parfocal Performance
Designed with a parfocal-type lineup, these eyepieces let you effortlessly switch between all six available magnifications with minimal refocusing. Say goodbye to the frustration of constant adjustments—whether you want to zoom in for a closer look or pull back for a wider view, these eyepieces make it effortless. Perfect for fast-paced observing sessions, they let you capture every detail.
Other Information
- Country of Manufacture: Taiwan
Founder Optics ALIEN Eyepieces: Long Eye-Relief for All Occasions!
The Founder Optics ALIEN eyepiece series packs serious observing power into a sleek, easy-to-use design. With the wide range of eyepiece magnifications, you can guarantee there’s one to suit every visual need—whether the Moon, planets, or tight deep-sky targets. These 7-element eyepieces deliver a noticeably flat and wide 55° field of view (FOV), perfect for soaking up every detail.
Looking for something for high-magnification views of lunar craters, planets or compact deep-sky objects? The ALIEN 5 mm eyepiece boasts a generous 20 mm eye relief. This means you can enjoy the view without pressing your face into the eyepiece. Fully multi-coated, edge-blackened optics serve up max light transmission and knockout contrast, while the pop-down rubber eyeguard shields your eyes from stray light for truly immersive viewing.
Standout Features:
- 5 mm focal length for high-magnification details.
- Putting comfort first with a long eye-relief, generous FOV, and rubber eye guard.
- Parafocal with other magnifications in the ALIEN series.
- Thoughtful features like blackened edges, multi-coatings, tapered barrel, and filter threading.
A Series Packed with Thoughtful Features
Built to last, the CNC-machined body features a secure rubber grip and a tapered nosepiece that helps keep the eyepiece in place, even if the thumbscrew isn’t fully tightened. Weighing just 6.5 oz (184 g) and standing about 4.33 in (110 mm) tall, with the eye guard extended. Compact, comfortable, and ready for any adventure! Plus, the 1.25-inch barrel is threaded for M28.5x0.6 filters, giving you even more ways to enhance your views.
Parfocal Performance
Designed with a parfocal-type lineup, these eyepieces let you effortlessly switch between all six available magnifications with minimal refocusing. Say goodbye to the frustration of constant adjustments—whether you want to zoom in for a closer look or pull back for a wider view, these eyepieces make it effortless. Perfect for fast-paced observing sessions, they let you capture every detail.
| Manufacturer | Founder Optics |
|---|---|
| Eyepiece Series | Alien Series |
| Focal Length | 5 mm |
| Barrel Size | 1.25 in |
| Apparent Field of View (Mfg Specified) | 55° |
| Eye Relief (Designed) | 20 mm |
| Filter Threads | M28.5x0.6 |
| Coatings | Fully Multi-coated |
| Lens Elements | 7 |
| Lens Groups | 4 |
| Blackened Lens Edges | Yes |
| Barrel Type | With safety undercut |
| Protective Storage Container Included | No |
| Protective Plastic Storage Container Size (Sold Separately) | Agena 52x80mm |
| Optical Design | Long Eye-Relief |
| Height (With Eyeguard Extended) | 4.33 in (110 mm) |
| Maximum Width | 1.73 in (44 mm) |
| End Caps | 2 |
| Eye Lens Diameter | 0.79 in (20 mm) |
| Parfocal | Yes |
| Rubber Eye Guard | Yes |
| Weight | 0.41 lb (184 g) |
| Country of Manufacture | Taiwan |
- ALIEN 5 mm eyepiece
- x2 dust caps
- ALIEN series eyepieces feature a generous 55° FOV and comfortable 20 mm long eye-relief.
- Bright images, low color aberration, superb sharp, crystal clear and impressive true image.
- 5 mm focal length for tight details of the Moon, planets and compact deep-sky targets.
- Parfocal type, minimal refocus required with other ALIEN eyepiece magnifications.
- Threaded for visual filters, and rubber eye guards for a more comfortable and enhanced experience.
Founder Optics ALIEN Eyepieces: Long Eye-Relief for All Occasions!
The Founder Optics ALIEN eyepiece series packs serious observing power into a sleek, easy-to-use design. With the wide range of eyepiece magnifications, you can guarantee there’s one to suit every visual need—whether the Moon, planets, or tight deep-sky targets. These 7-element eyepieces deliver a noticeably flat and wide 55° field of view (FOV), perfect for soaking up every detail.
Looking for something for high-magnification views of lunar craters, planets or compact deep-sky objects? The ALIEN 5 mm eyepiece boasts a generous 20 mm eye relief. This means you can enjoy the view without pressing your face into the eyepiece. Fully multi-coated, edge-blackened optics serve up max light transmission and knockout contrast, while the pop-down rubber eyeguard shields your eyes from stray light for truly immersive viewing.
Standout Features:
- 5 mm focal length for high-magnification details.
- Putting comfort first with a long eye-relief, generous FOV, and rubber eye guard.
- Parafocal with other magnifications in the ALIEN series.
- Thoughtful features like blackened edges, multi-coatings, tapered barrel, and filter threading.
A Series Packed with Thoughtful Features
Built to last, the CNC-machined body features a secure rubber grip and a tapered nosepiece that helps keep the eyepiece in place, even if the thumbscrew isn’t fully tightened. Weighing just 6.5 oz (184 g) and standing about 4.33 in (110 mm) tall, with the eye guard extended. Compact, comfortable, and ready for any adventure! Plus, the 1.25-inch barrel is threaded for M28.5x0.6 filters, giving you even more ways to enhance your views.
Parfocal Performance
Designed with a parfocal-type lineup, these eyepieces let you effortlessly switch between all six available magnifications with minimal refocusing. Say goodbye to the frustration of constant adjustments—whether you want to zoom in for a closer look or pull back for a wider view, these eyepieces make it effortless. Perfect for fast-paced observing sessions, they let you capture every detail.
Other Information
- Country of Manufacture: Taiwan
| Manufacturer | Founder Optics |
|---|---|
| Eyepiece Series | Alien Series |
| Focal Length | 5 mm |
| Barrel Size | 1.25 in |
| Apparent Field of View (Mfg Specified) | 55° |
| Eye Relief (Designed) | 20 mm |
| Filter Threads | M28.5x0.6 |
| Coatings | Fully Multi-coated |
| Lens Elements | 7 |
| Lens Groups | 4 |
| Blackened Lens Edges | Yes |
| Barrel Type | With safety undercut |
| Protective Storage Container Included | No |
| Protective Plastic Storage Container Size (Sold Separately) | Agena 52x80mm |
| Optical Design | Long Eye-Relief |
| Height (With Eyeguard Extended) | 4.33 in (110 mm) |
| Maximum Width | 1.73 in (44 mm) |
| End Caps | 2 |
| Eye Lens Diameter | 0.79 in (20 mm) |
| Parfocal | Yes |
| Rubber Eye Guard | Yes |
| Weight | 0.41 lb (184 g) |
| Country of Manufacture | Taiwan |
- ALIEN 5 mm eyepiece
- x2 dust caps
Founder Optics 1.25" ALIEN Long Eye-Relief Eyepiece - 5mm