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EXPLORE SCIENTIFIC 52° LER Eyepiece 20mm Ar

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Guides & Tips

FAQ - Frequently Asked Questions

That is normal. Finder scopes are only used to make objects easy to locate. The image orientation does not matter for observation.

  • Alt-azimuth: easy to use, moves horizontally and vertically
  • Equatorial: enables precise tracking of objects with only one axis – ideal for high magnifications and astrophotography

  • Moon: from 30 mm
  • Planets: from 100 mm
  • Deep sky: from 150 mm
Are you a member of an astronomy club? Find out here what your benefits are.
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Product and safety instructions


Manufacturer: 
Bresser GmbH, Gutenbergstraße 2, 46414 Rhede

Contact: 
www.bresser.de


Warning notes
  • General safety instructions DANGER Risk of eye injuries! Never look directly at the sun or near the sun through this device. There is a risk of blindness! Children should only use the device under supervision. Keep packaging materials (plastic bags, rubber bands, etc.) away from children! There is a risk of suffocation! FIRE HAZARD! Do not expose the device especially the lenses to direct sunlight! The light concentration could cause fires. RISK of material damage! Do not dismantle the device! In case of a defect, please contact your dealer. They will contact the service center and may send the device in for repair. Do not expose the device to temperatures above 60°C!
  • Never look at the sun through an eyepiece/telescope without a certified protection filter. A moon filter can never be used for solar observation. The moon filter is only suitable for moon observation. The solar filter must be mounted in front of the telescope opening, not at the eyepiece. Otherwise, the concentrated light beam through the optics will immediately destroy the filter foil, leading to severe eye damage, including permanent blindness.
  • Never leave the optics unattended. Children and inexperienced adults could point the telescope at the sun without proper precautions and lose their eyesight.
  • Do not expose the device to high temperatures.
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Accessories

EXPLORE SCIENTIFIC Filter Set 1 Moon & Planets from 50mm (2'')
Filter Set 1 is recommended for Moon & Planets from 50mm (2'') Aperture Set 1 includes the following filters: Explore Scientific Filter 1.25" Light Yellow No.8 - 0310268 Watching the Moon surface through the filter, the contrasts will enormously increase. Same with planet Mars. On the huge planet Jupiter, when using the filter, you can even see the contrasts between the cloud-bands and a lot more details. Starting with a telescope diameter of 8“ and a clear sight, you even get to see various details of Saturn. Explore Scientific Filter 1.25" Orange No.21 - 0310273 This one really supports the detection of the dark areas on the planet Mars. The details of the clouds of Saturn and Jupiter are also so much more visible through the Filter. Explore Scientific Filter 1.25" Blue No.80A - 0310264 The color of light blue really supports watching the high clouds on Mars. The contrast increases. The dark red structures will be shown even darker, so this is the perfect filter for watching the big red Flecks on the gas planet Jupiter. The rings of Saturn will be accentuated, the structures of the Venus Atmosphere will be even finer. EXPLORE SCIENTIFIC 1.25" Filter Grey ND0.9 - 0310245 The neutral density filter transmits light uniformly across the entire visual spectrum. It serves as an excellent filter to reduce glare and irradiation when observing the Moon with any telescope 4"(10.2cm) and larger. The ND96 filter may also be employed in the splitting of close double stars where one of the binary pair significantly exceeds the other in brightness. What ist a color Filter for and do we really need it? Color Filters darken the light slightly, that reaches the eye or the sensor of the camera. This eliminates for instance stronger transitions. The result is that your picture turns out with more contrast which automatically shows more details. FEATURES Made from high-quality optical glass Filter glass is absolutely parallel All optical surfaces have anti reflex coatings Filter housing from black anodized aluminum Filter threads on both ends (female/male) Multiple filters usage is possible SCOPE OF DELIVERY 4pcs color filter 4pcs protection-case

Available

£42.00*
EXPLORE SCIENTIFIC Filter Set 2 Moon & Planets from 100mm (4")
Filter Set 2 is recommended for Moon & Planets from 100mm (4") Aperture Set 2 includes the following filters: Explore Scientific Filter 1.25" Green No.56 - 0310262 The green filter is to increase the contrasts enormously between the red and the blue regions of the cloud structures on the gas planets Jupiter and Saturn. Seeing our Earth Moon through the green filter, the contrasts of each ray crater become clearly more visible. Explore Scientific Filter 1.25" Orange No.21 - 0310273 This one really supports the detection of the dark areas on the planet Mars. The details of the clouds of Saturn and Jupiter are also so much more visible through the Filter. Explore Scientific Filter 1.25" Yellow No.12 - 0310267 Watching the Moon surface through the filter, the contrasts will enormously increase. Same with planet Mars. On the huge planet Jupiter, when using the filter, you can even see the contrasts between the cloud-bands and a lot more details. Starting with a telescope diameter of 8“ and a clear sight, you even get to see various details of Saturn. Explore Scientific Filter 1.25" Blue No.80A - 0310264 The color of light blue really supports watching the high clouds on Mars. The contrast increases. The dark red structures will be shown even darker, so this is the perfect filter for watching the big red Flecks on the gas planet Jupiter. The rings of Saturn will be accentuated, the structures of the Venus Atmosphere will be even finer. What ist a color Filter for and do we really need it? Color Filters darken the light slightly, that reaches the eye or the sensor of the camera. This eliminates for instance stronger transitions. The result is that your picture turns out with more contrast which automatically shows more details. FEATURES Made from high-quality optical glass Filter glass is absolutely parallel All optical surfaces have anti reflex coatings Filter housing from black anodized aluminum Filter threads on both ends (female/male) Multiple filters usage is possible SCOPE OF DELIVERY 4pcs color filter protection-case

Available

£42.00*
EXPLORE SCIENTIFIC Filter Set 3 Moon & Planets from 150mm (6")
Filter Set 3 is recommended for Moon & Planets from 150mm (6") Aperture Set 3 includes the following filters: Explore Scientific Filter 1.25" Light Blue No.82A - 0310265 The color of light blue really supports watching the high clouds on Mars. The contrast increases. The dark red structures will be shown even darker, so this is the perfect filter for watching the big red Flecks on the gas planet Jupiter. The rings of Saturn will be accentuated, the structures of the Venus Atmosphere will be even finer. Explore Scientific Filter 1.25" Violet No.47 - 0310272 The purple filter is perfect for watching Venus. Seeing through it, the dark clouds of the Venus atmosphere become even better visible. He also clears up the structures of the rings around Saturn. Using big openings and having a clear sight this filter is also good for watching Merkur. Explore Scientific Filter 1.25" Light Red No.23A - 0310271 The blue/blue green light is totally blocked. The contrast between the card and the lighter zones will enormously increase. This is truly helpful when you watch Jupiter or Saturn. Or for mars, watching the poles. Explore Scientific Filter 1.25" Yellow-Green No.11 - 0310269 Watching the Moon surface through the filter, the contrasts will enormously increase. Same with planet Mars. On the huge planet Jupiter, when using the filter, you can even see the contrasts between the cloud-bands and a lot more details. Starting with a telescope diameter of 8“ and a clear sight, you even get to see various details of Saturn. What ist a color Filter for and do we really need it? Color Filters darken the light slightly, that reaches the eye or the sensor of the camera. This eliminates for instance stronger transitions. The result is that your picture turns out with more contrast which automatically shows more details. FEATURES Made from high-quality optical glass Filter glass is absolutely parallel All optical surfaces have anti reflex coatings Filter housing from black anodized aluminum Filter threads on both ends (female/male) Multiple filters usage is possible SCOPE OF DELIVERY 4pcs color filter 4pcs protection-case

Available

£42.00*
EXPLORE SCIENTIFIC Filter Set 4 Moon & Planets from 200mm (8")
Filter Set 4 is recommended for Moon & Planets from 200mm (8'') Aperture Set 4 includes the following filters: Explore Scientific Filter 1.25'' Green No.56 - 0310262 The green filter is to increase the contrasts enormously between the red and the blue regions of the cloud structures on the gas planets Jupiter and Saturn. Seeing our Earth Moon through the green filter, the contrasts of each ray crater become clearly more visible. Explore Scientific Filter 1.25'' Dark Blue No.38A - 0310263 The color of light blue really supports watching the high clouds on Mars. The contrast increases. The dark red structures will be shown even darker, so this is the perfect filter for watching the big red Flecks on the gas planet Jupiter. The rings of Saturn will be accentuated, the structures of the Venus Atmosphere will be even finer. Works well starting with a 10'' aperture. Explore Scientific Filter 1.25'' Orange No.21 - 0310273 This one really supports the detection of the dark areas on the planet Mars. The details of the clouds of Saturn and Jupiter are also so much more visible through the Filter. Explore Scientific Filter 1.25'' Light Yellow No.8 - 0310268 Watching the Moon surface through the filter, the contrasts will enormously increase. Same with planet Mars. On the huge planet Jupiter, when using the filter, you can even see the contrasts between the cloud-bands and a lot more details. Starting with a telescope diameter of 8'' and a clear sight, you even get to see various details of Saturn. What ist a color Filter for and do we really need it ? Color Filters darken the light slightly, that reaches the eye or the sensor of the camera. This eliminates for instance stronger transitions. The result is that your picture turns out with more contrast which automatically shows more details. FEATURES Made from high-quality optical glass Filter glass is absolutely parallel All optical surfaces have anti reflex coatings Filter housing from black anodized aluminum Filter threads on both ends (female/male) Multiple filters usage is possible SCOPE OF DELIVERY 4pcs color filter 4pcs protection-case

Available

£42.00*
EXPLORE SCIENTIFIC 1.25" Variable Polarizing Filter
Universally usable variable polarizing filter with a  1.25" filter thread.This variable polarizing filter allows for a continuous adjustment of the image brightness. This is very helpful to level strong differences in contrast of different observation objects individually. Particularly for lunar and planetary observations but also for solar observations this filter prevents an outshining of details.Solar observations ONLY together with an adequate solar filter !!! Particularly when a Herschel wedge is used and with large objective lens apertures the use of the variable polarizing filter can reduce the brightness of the observation object to a confortable level. The large adjustment range of 40% to 1% light transmission and the neutral grey filter effect create a comfortable and unadulterated image.The handling is very simple. The desired filtering level is set by turning the two sides of the housing against each other.A 1.25" filter thread on both sides (female/male) allow for the simultaneous use of additional colour filters.FEATURESvariable polarizing filterindividually adjustable image brightnessmade from high-quality optical glassblack anodized aluminium housing1.25" filter thread on both sidesSCOPE OF DELIVERYpolarizing filterprotective box

Available

£58.00*
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EXPLORE SCIENTIFIC 52° LER Eyepiece 4,5mm Ar
High power eyepieces (e.g. 3mm to 10mm) are used not only for obvious observations of planets and double stars, but can be employed for bright, compact deep sky objects. Not only will the scale of an object like a planetary nebula or globular cluster be impressive as it fills the eyepiece FOV, but the background sky will be very dark as the contrast effect increases with added magnification, provided that the atmospheric seeing conditions are favorable enough to reveal a sharp image. The 4.5mm is a popular choice for a wide variety of telescopes, producing some of the highest magnification views that most astronomers will observe at.Comfort, Quality, Value. The Explore Scientific 52° LER Series Most short focal length eyepieces are excellent flat-field multi-element oculars that can transform your visual astronomy experience. With an apparent field of view of 52 degrees, these eyepieces offer incredible value in a very nice eyepiece. Expect exceptional quality and value versus a comparably priced Plossl.  These eyepieces are the choice for observers wearing glasses - with excellent performance and durability. The rubber inlet and the foldable eyecups make handling and using in the field easy. The patented EMD"-coating produces high contrast images and prevents reflexes and ghosting. The argon purging effectively prevents internal fogging, and you don´t have to deal with dirt, fungus or cleansing fluids getting between the lenses. The eyepieces are sealed - this makes sure you will be able to enjoy these eyepieces for many years to come.SPECIFICATIONSLarge eye distance, large field and great image sharpnessExcellent viewing position for people with glassesExcellent field sharpness even with fast optics52° apparent field of viewArgon-purging prevents internal fogging, the sealing facilitates cleaningPatented EMD"-coating to maximize contrastBlackened lens edges to avoid reflexesAll eyepieces of this series are parfocalStainless steel barrel with conical security cutoffDust covers and protective bag includedSCOPE OF DELIVERY52° EyepieceDust coversProtective bag

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EXPLORE SCIENTIFIC 52° LER Eyepiece 10mm Ar
Mid-range high power eyepieces like the 10 mm are instrumental when transitioning through magnifications to observe an object until it is best seen. There are several aspects that have to come together when observing at high powers: good-to-perfect atmospheric seeing conditions; telescope optics that are collimated; a telescope that is acclimated to the ambient temperature; brightness and size of the object being observed are just a few aspects to consider. The observing challenges are high, but the rewards of observing at high power with razor sharp views are unforgettable. Comfort, Quality, Value. The Explore Scientific 52° LER Series Most short focal length eyepieces are excellent flat-field multi-element oculars that can transform your visual astronomy experience. With an apparent field of view of 52 degrees, these eyepieces offer incredible value in a very nice eyepiece. Expect exceptional quality and value versus a comparably priced Plössl. These eyepieces are the choice for observers wearing glasses - with excellent performance and durability. The rubber inlet and the foldable eyecups make handling and using in the field easy. The patented EMD-coating produces high contrast images and prevents reflexes and ghosting. The argon purging effectively prevents internal fogging, and you don't have to deal with dirt, fungus or cleansing fluids getting between the lenses. The eyepieces are sealed - this makes sure you will be able to enjoy these eyepieces for many years to come.SPECIFICATIONSLarge eye distance, large field and great image sharpness Excellent viewing position for people with glassesExcellent field sharpness even with fast optics52° apparent field of viewArgon-purging prevents internal fogging, the sealing facilitates cleaningPatented EMD-coating to maximize contrastBlackened lens edges to avoid reflexesAll eyepieces of this series are parfocalStainless steel barrel with conical security cutoffDust covers and protective bag includedSCOPE OF DELIVERY52° EyepieceDust coversProtective bag

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EXPLORE SCIENTIFIC 52° LER Eyepiece 15mm Ar
Solidly in the mid-magnification range for most amateur telescopes, the 15mm is a true workhorse for visual observers. If you love deep sky observing, eyepieces in this focal length range not only give healthy increases in magnification, but the contrast enhancement of giving a darker background sky can make all the difference of how galaxies and nebulae appear under suburban skies.Comfort, Quality, Value. The Explore Scientific 52° LER Series mid-range focal length eyepieces are excellent flat-field multi-element oculars that can transform your visual astronomy experience. With an apparent field of view of 52 degrees, these eyepieces offer incredible value in a very nice eyepiece. Expect exceptional quality and value versus a comparably priced Plossl.  These eyepieces are the choice for observers wearing glasses - with excellent performance and durability. The rubber inlet and the foldable eyecups make handling and using in the field easy. The patented EMD"-coating produces high contrast images and prevents reflexes and ghosting. The argon purging effectively prevents internal fogging, and you don´t have to deal with dirt, fungus or cleansing fluids getting between the lenses. The eyepieces are sealed - this makes sure you will be able to enjoy these eyepieces for many years to come.SPECIFICATIONSLarge eye distance, large field and great image sharpnessExcellent viewing position for people with glassesExcellent field sharpness even with fast optics52° apparent field of viewArgon-purging prevents internal fogging, the sealing facilitates cleaningPatented EMD-coating to maximize contrastBlackened lens edges to avoid reflexesAll eyepieces of this series are parfocalStainless steel barrel with conical security cutoffDust covers and protective bag includedSCOPE OF DELIVERY52° EyepieceDust coversProtective bag

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EXPLORE SCIENTIFIC 2" O-III Nebula Filter
blocking the annoying  lightEXPLORE SCIENTIFIC O-III filteremission nebulaeEXPLORE SCIENTIFIC O-III nebula filter only the two  lines of the oxygen can pass the filterEXPLORE SCIENTIFIC nebula filters FEATURESenables the observation of so called emission nebulaeblocks almost the entire artificial lightonly the two emission lines of ionised oxygen passes the filterWHAT'S INCLUDED1x 2" O-III nebula filter

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£87.00* £109.00* (20.18% saved)
BRESSER BinoViewer Deluxe 1.25''
You see better with two eyesThe BRESSER BinoViewer Deluxe makes it possible to observe astronomical objects in a relaxed way with both eyes and with considerably more detail than using one eye. The images created of the moon, planets and globular clusters are particularly impressive. But also with deep-sky objects such as the Orion Nebula the detection of details is much easier. At the same time this binoviewer is very easy to handle. Thanks to the newly patented optical system you can get into focus with any telescope. All you need is a pair of identical eyepieces to enjoy this dramatic and immersive viewing experience.How to use the BinoViewer? Since the BRESSER BinoViewer Deluxe does not require an additional light path (back focus), it can be used with any telescope - including Newtonians and short focus refracting telescopes, which traditionally suffered when using standard binoviewers. No light path corrector or similar accessory is necessary. If a standard 1.25'' eyepiece can be focused, the binoviewer will also work. The eyepiece focal length and field of view size of the eyepieces used are fully retained. As with binoculars one eyepiece is focused first using the telescope focuser. Then the second eyepiece can be brought into focus using the helical focuser on the binoviewer. The required interpupillary distance is then elegantly adjusted to a range of 58–74mm with the help of a linear sliding mechanism, with graduated marker, to help you find your ideal interocular setting quickly.  Self-centring helical eyepiece grips, rather than side-mounted thumbscrew eyepiece retainers are used, decreasing the chance of offsetting collimation of both eyepiece to each other.  The fact that this design of binoviewer uses a well-engineered linear slide mechanism to adjust interpupillary distance, rather than a cheaper-to-produce traditional hinged design also helps retention of collimation.Which objects can be observed with this accessory?Actually, all objects that were previously observed with the telescope in question, but only monocularly with one eye. Because there is no magnification factor at the binoviewer, even low magnifications can be achieved. This makes not only the moon, planets and globular clusters, but also the brighter deep-sky objects very interesting observation targets. The use of two eyes leads to a more relaxed view than using one eye alone.  Although true depth of field viewing at infinity is a little beyond most telescopes and binoviewers, users will note how the human brain attempts to impose depth of field ("3d-like") effects on stereo views through binoviewers.  The biggest difference that most observers comment upon when comparing views through binoviewers like these, as opposed to single monocular eyepiece views, is the extra detail that can be seen in most observable targets.  Relaxed viewing and extra detail in objects are the two main benefits of binoviewing, which the BRESSER Bino Viewer Deluxe 1.25'' delivers in abundance.Also ideal as an accessory for solar telescopesA very special application is the use of the BRESSER BinoViewer Deluxe in combination with all solar telescopes. The spherical shape of the sun with all its surface details is shown very impressively.  The depth of field effects of seeing filaments silhouetted against the solar surface are particularly enjoyable to observe.Important note: Do not use the BRESSER Binoviwer Deluxe without a suitable solar telescope or a safe solar filter in front of the telescopes objective lens . Otherwise, there is an acute risk of going blind.High-quality mechanics and materialsThe entire BRESSER BinoViewer Deluxe is made of high-quality materials. Except for the outer plastic covers all components are made of anodised aluminium. Particularly remarkable are the low-backlash sliding mechanism for adjusting the interpupillary distance and the precise rotary clamping of both eyepiece adapters. The wide clamping surface holds the eyepieces in place securely and also centres them automatically on the optical axis. The one-sided dioptric adjustment has a backlash-free helical drive and enables the finest corrections. For safe transport a high-quality hard-shell transport case is included in the scope of delivery.Which eyepieces can be used?All eyepieces with a 1.25'' barrel and a field stop of up to 22mm. Depending on the interpupillary distance the outer diameter of the eyepiece housing should not exceed a value of approximately 50 mm.Filter thread 1.25'' availableNo 2nd filter sets are necessary to operate the BRESSER Binocular Approach Deluxe. The desired colour or nebula filter can be screwed directly into the 1.25'' nosepiece. in this configuration, when changing the eyepieces to affect a change in magnification, no swapping of filters is necessary.  Unique mirror-lens system with Ohara (Japan) lanthanum glass material The BRESSER Binocular Viewer Deluxe is equipped with a unique mirror-lens system. This has the advantage of higher light transmission and less color aberration. The resulting image is simply brighter and sharper. To achieve this the exclusive Ohara (Japan) lanthanum glass material has been used and in addition all optical surfaces are equipped with a full multi-layer broadband coating. Finally the beam-splitting mirror has a 99% dielectric coating and completes the excellent optical design.FEATURESEnables binocular observations with all telescopesRelaxed and comfortable viewingThree-dimensional viewing experienceSuitable for all telescopes with 1.25'' eyepiece connectionNo additional light path requiredNo magnification factor at the binocular attachmentEven low magnifications with large fields of view are achievableFor observing moon, planets and deep sky objectsPrecise and robust mechanicsSliding mechanism to adjust the interpupillary distanceDioptric compensation via fine helical driveWide eyepiece rotation clamp with automatic centeringFilter thread 1.25'' (M28.5 x 0.6mm) availableLens and mirror design made of finest Ohara (Japan) lanthanum glass materialAdvanced broadband multilayer coating on all optical surfaces99 % dielectric-coated beam-splitting mirrorHigh-quality hard-shell carrying case includedWHAT'S INCLUDEDBino Viewer DeluxeDust capsCarrying case 

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EXPLORE SCIENTIFIC Precision AZ Adjuster for iEXOS-100 Mount
The Azimuth Adjuster Adapter is designed for use on the iEXOS-100 tripod, but requires slightly modification of the tripod base. See the manual for details of the required modification. This device allows iEXOS-100 users to make fine azimuth adjustments for precise polar alignment. Customer comment: I tried it out for the first time last night. It's now even easier to get polar aligned (using Sharpcap).... It's an easy installation with the newly included parts to install the post and the clear instruction manual. Thanks ES! - Jay Sanchez (USA) FEATURES Allows iEXOS-100 users to make fine azimuth adjustments Quick and comfortable adustment for polar alignment Full aluminum design - no plastic Only slightly modification necessary (one hole to be drilled) SCOPE OF DELIEVERY Precision AZ Adjuster Installation manual

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