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LUNT Blue-Glass 20mm for B400 to B1800 blocking-filters

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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
  • Safety instructions: There are certain dangers when observing the sun, regardless of the telescope used. Lunt-Solar-Systems places great emphasis on the safety of their products during manufacture. Your safety is the highest priority, and we ask that you carefully read the telescope manual before beginning solar observation. Please never disassemble the telescope! Never use it if it has been modified or damaged in any way! Always contact our customer service if you have any questions regarding the safety of your instrument. Never look at the sun with an unprotected eye or with a telescope not intended for solar observation! Never leave your telescope unattended while it is pointed at the sun! Other people who are unfamiliar with it might attempt to replace the block filter with another prism, unaware of how critical this filter is for safety. The components of Lunt-Solar-Systems telescopes are not interchangeable with those of other manufacturers. Lunt-Solar-Systems solar telescopes contain several different optical elements that have been precisely adjusted and mounted during manufacture. These systems require no maintenance. Never disassemble the telescope. Doing so will void the warranty, potentially leading to expensive repairs, and may cause future damage to your instrument, compromising your safety! Most Lunt-Solar-Systems telescopes and filters include a very sensitive optical component called an Etalon. These Etalons are built into the system to protect them as best as possible. Countless considerations have been made to ensure the best performance of this "heart" of every system, even under the daily stresses it inevitably faces, such as shocks and vibrations during transport or regular use. Nevertheless, it should never be dropped. Improper use of the telescope can damage the Etalon (not a warranty case) and render the system unusable until repaired. The instrument should always be stored in its original packaging or in the optional transport case (item number 0554010). Like any optical precision instrument, it should be stored in a dry environment. With proper care, you will enjoy your instrument for a lifetime!
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LUNT Grease for Pressure-Tuner at MT & THa solar telescopes
Spare part for Pressure-Tuner of MT and THa series H-alpha solar telescopes from LUNT SOLAR SYSTEMSFor example, if the O-rings have been changed on a Pressure-Tuner of a Lunt Solar Systems H-alpha solar telescope, the Pressure-Tuner can be re-greased with this grease. The grease can be applied to the piston with the O-rings and to the threads of the brass cylinder on the Pressure-Tuner. It keeps the Pressure-Tuner running smoothly and seals it.Please note:Do not use too much grease inside the brass cylinder. The grease must not get into the air passage at the bottom of the brass cylinder, otherwise the Etalon could be damaged in the worst case.FEATURESLithium grease with Teflon contentVery good sealing propertiesHigh adhesion and good corrosion protectionTemperature stable from -20 to +120° CelsiusConstant viscosity during temperature fluctuationsSCOPE OF DELIVERYSpare part: Grease for Pressure-Tuner of MT and THa H-alpha solar telescopes from Lunt Solar Systems

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LUNT O-ring 32mm for Pressure-Tuner at MT & THa solar telescopes
Spare part for Pressure-Tuner of MT and THa series H-alpha solar telescopes from LUNT SOLAR SYSTEMSTwo rubber O-rings are installed into the Pressure-Tuner of Lunt Solar Systems solar telescopes to seal the air-pressure tuning system. Over time, the rubber of this O-rings can age and become porous, whereby the air-pressure can then no longer be maintained. When this happens, a old O-ring can be replaced by this spare part. The replacement is simple and can be done by the user. Installation instructions can be found here under the tab "Manuals" as a PDF file for download.Please be sure to note:Depending on the production series, the diameters of the Pressure-Tuner pistons can vary slightly. There are pistons for O-rings with 32mm inner diameter and 40mm outer diameter, and pistons for O-rings with 34mm inner diameter and 42mm outer diameter. Please check the diameter of your old O-rings, this spare part is an O-ring with 32mm inner diameter and 40mm outer diameter.If you need the larger O-ring with 34mm inner diameter and 42mm outer diameter, this is the spare part with item number 0558340.The LS50THa telescopes have Pressure-Tuners with smaller diameters, for these you will need replacement O-rings with item number 0558320.After replacing a O-ring, the piston and cylinder of the Pressure-Tuner can be re-greased with grease available under item number 0558350.FEATURESInner diameter: 32mmOuter diameter: 40mmCannot be used separately, only as a replacement part on the Pressure-Tuner of MT and THa telescopes from Lunt Solar Systems.It does not matter what blocking-filter is at the MT or THa telescope.SCOPE OF DELIVERYSpare part one O-ring with 32mm inner diameter and 40mm outer diameter for Pressure-Tuner of MT and THa H-alpha solar telescopes from Lunt Solar Systems

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LUNT O-ring 34mm for Pressure-Tuner at MT & THa solar telescopes
Spare part for Pressure-Tuner of MT and THa series H-alpha solar telescopes from LUNT SOLAR SYSTEMSTwo rubber O-rings are installed into the Pressure-Tuner of Lunt Solar Systems solar telescopes to seal the air-pressure tuning system. Over time, the rubber of this O-rings can age and become porous, whereby the air-pressure can then no longer be maintained. When this happens, a old O-ring can be replaced by this spare part. The replacement is simple and can be done by the user. Installation instructions can be found here under the tab "Manuals" as a PDF file for download.Please be sure to note:Depending on the production series, the diameters of the Pressure-Tuner pistons can vary slightly. There are pistons for O-rings with 32mm inner diameter and 40mm outer diameter, and pistons for O-rings with 34mm inner diameter and 42mm outer diameter. Please check the diameter of your old O-rings, this spare part is an O-ring with 34mm inner diameter and 42mm outer diameter.If you need the smaller O-ring with 32mm inner diameter and 40mm outer diameter, this is the spare part with item number 0558330.The LS50THa telescopes have Pressure-Tuners with smaller diameters, for these you will need replacement O-rings with item number 0558320.After replacing a O-ring, the piston and cylinder of the Pressure-Tuner can be re-greased with grease available under item number 0558350.FEATURESInner diameter: 34mmOuter diameter: 42mmCannot be used separately, only as a replacement part on the Pressure-Tuner of MT and THa telescopes from Lunt Solar Systems.It does not matter what blocking-filter is at the MT or THa telescope.SCOPE OF DELIVERYSpare part one O-ring with 34mm inner diameter and 42mm outer diameter for Pressure-Tuner of MT and THa H-alpha solar telescopes from Lunt Solar Systems

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LUNT O-ring for Pressure-Tuner at LS50THa solar telescopes
​Spare part for Pressure-Tuner of LS50THa H-alpha solar telescopes from LUNT SOLAR SYSTEMSA rubber O-ring is installed into the Pressure-Tuner of Lunt Solar Systems LS50THa solar telescopes to seal the air-pressure tuning system. Over time, the rubber of this O-ring can age and become porous, whereby the air-pressure can then no longer be maintained. When this happens, the old O-ring can be replaced by this spare part. The replacement is simple and can be done by the user. Installation instructions can be found here under the tab "Manuals" as a PDF for download.After replacing the O-ring, the piston and cylinder of the Pressure-Tuner can be re-greased with grease available under part number 0558350.Please note that this spare part can only be used on the Lunt Solar Systems LS50THa H-alpha solar telescopes. If the problem occurs on the larger THa or MT series telescopes, the larger O-rings with part numbers 0558330 or 0558340 must be used there.FEATURESInner-diameter: 31mmOuter-diameter: 39mmCannot be used separately, only as a replacement part on the Pressure-Tuner of the LS50THa telescopes from Lunt Solar Systems.It does not matter what blocking filter is at the LS50THaSCOPE OF DELIVERYSpare part one O-ring for pressure tuner of LS50THa

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Adapter T2 to 2", for 2" eyepieces to blocking filter
Adapter T2 to 2", takes for example 2" eyepieces to Lunt Solar Systems blocking-filters.This adapter offers a T2 female thread at the telescope-side, and a 2" connection at the eyepiece-side.For example you want to use your 2" eyepieces at Lunt Solar Systems telescopes or filters? All you need is this adapter. Simply remove the 1.25" eyepiece tube from your blocking-filter, and thread on this 2" adapter. It takes T2 threading to a 2" eyepiece tube.You can use 2" eyepieces with this adapter at:• LUNT H-alpha telescopes (not at LS35THa!)• the blocking-filters of LUNT H-alpha filter systems• LUNT Ca-K modules• all telescopes/adapter with T2 male threadTechnical data:• Thread at telescope-side: T2 female thread• Eyepiece connection: 2"Delivered by order:• Adapter T2 to 2"(Blocking Filter not included)

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LUNT O-ring for Pressure-Tuner at LS50THa solar telescopes
​Spare part for Pressure-Tuner of LS50THa H-alpha solar telescopes from LUNT SOLAR SYSTEMSA rubber O-ring is installed into the Pressure-Tuner of Lunt Solar Systems LS50THa solar telescopes to seal the air-pressure tuning system. Over time, the rubber of this O-ring can age and become porous, whereby the air-pressure can then no longer be maintained. When this happens, the old O-ring can be replaced by this spare part. The replacement is simple and can be done by the user. Installation instructions can be found here under the tab "Manuals" as a PDF for download.After replacing the O-ring, the piston and cylinder of the Pressure-Tuner can be re-greased with grease available under part number 0558350.Please note that this spare part can only be used on the Lunt Solar Systems LS50THa H-alpha solar telescopes. If the problem occurs on the larger THa or MT series telescopes, the larger O-rings with part numbers 0558330 or 0558340 must be used there.FEATURESInner-diameter: 31mmOuter-diameter: 39mmCannot be used separately, only as a replacement part on the Pressure-Tuner of the LS50THa telescopes from Lunt Solar Systems.It does not matter what blocking filter is at the LS50THaSCOPE OF DELIVERYSpare part one O-ring for pressure tuner of LS50THa

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LUNT Grease for Pressure-Tuner at MT & THa solar telescopes
Spare part for Pressure-Tuner of MT and THa series H-alpha solar telescopes from LUNT SOLAR SYSTEMSFor example, if the O-rings have been changed on a Pressure-Tuner of a Lunt Solar Systems H-alpha solar telescope, the Pressure-Tuner can be re-greased with this grease. The grease can be applied to the piston with the O-rings and to the threads of the brass cylinder on the Pressure-Tuner. It keeps the Pressure-Tuner running smoothly and seals it.Please note:Do not use too much grease inside the brass cylinder. The grease must not get into the air passage at the bottom of the brass cylinder, otherwise the Etalon could be damaged in the worst case.FEATURESLithium grease with Teflon contentVery good sealing propertiesHigh adhesion and good corrosion protectionTemperature stable from -20 to +120° CelsiusConstant viscosity during temperature fluctuationsSCOPE OF DELIVERYSpare part: Grease for Pressure-Tuner of MT and THa H-alpha solar telescopes from Lunt Solar Systems

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BRESSER Single Polarizing Filter 1.25"
This polarizing filter can be used for example at the Lunt Solar Systems 1.25" White-Light Herschel-wedge (0558211).FEATURESLinear polarizing filterFilter mount with 1.25" filter threadSCOPE OF DELIVERY1x 1.25" polarizing filter

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LUNT O-ring 34mm for Pressure-Tuner at MT & THa solar telescopes
Spare part for Pressure-Tuner of MT and THa series H-alpha solar telescopes from LUNT SOLAR SYSTEMSTwo rubber O-rings are installed into the Pressure-Tuner of Lunt Solar Systems solar telescopes to seal the air-pressure tuning system. Over time, the rubber of this O-rings can age and become porous, whereby the air-pressure can then no longer be maintained. When this happens, a old O-ring can be replaced by this spare part. The replacement is simple and can be done by the user. Installation instructions can be found here under the tab "Manuals" as a PDF file for download.Please be sure to note:Depending on the production series, the diameters of the Pressure-Tuner pistons can vary slightly. There are pistons for O-rings with 32mm inner diameter and 40mm outer diameter, and pistons for O-rings with 34mm inner diameter and 42mm outer diameter. Please check the diameter of your old O-rings, this spare part is an O-ring with 34mm inner diameter and 42mm outer diameter.If you need the smaller O-ring with 32mm inner diameter and 40mm outer diameter, this is the spare part with item number 0558330.The LS50THa telescopes have Pressure-Tuners with smaller diameters, for these you will need replacement O-rings with item number 0558320.After replacing a O-ring, the piston and cylinder of the Pressure-Tuner can be re-greased with grease available under item number 0558350.FEATURESInner diameter: 34mmOuter diameter: 42mmCannot be used separately, only as a replacement part on the Pressure-Tuner of MT and THa telescopes from Lunt Solar Systems.It does not matter what blocking-filter is at the MT or THa telescope.SCOPE OF DELIVERYSpare part one O-ring with 34mm inner diameter and 42mm outer diameter for Pressure-Tuner of MT and THa H-alpha solar telescopes from Lunt Solar Systems

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LUNT LS130MT/B3400R&P Multipurpose APO Telescope for Sun + Night-Sky
Modular designed multipurpose telescope, both for observing the sun in the H-alpha wavelength, as well as for night sky observations. Easy conversion between the different applications with a few simple steps. 3-lens apochromatic telescope with FPL-51 glass, 130mm aperture and 910mm focal length - excellent image quality for H-Alpha solar observation and also for observing the starry sky at night. With innovative air pressure tuning system, good 2 inch (50.8mm) R&P focuser, and B3400 blocking filter. Solar observing in H-alpha: The LS130MT/B3400 is a complete telescope for observing the sun in H-alpha light, with 130mm free aperture (no central obstruction) and 910mm focal length. The H-alpha wavelength is the most impressive way to observe the sun, showing protuberances at the sun's edge, filaments and flares on the surface, and much more. An internal Etalon filter achieves a bandwidth of <0.7 Angstrom with the innovative air pressure tuning system Pressure-Tuner. Tuning is done by slightly changing the air pressure in a pressure chamber inside the telescope. This changes the refractive index of the air, making it easy to tune to the H-alpha line. The pressure tuner guarantees a homogeneous image, without central obstruction, and a permanently protected Etalon without erosion. A set of collimating lenses installed in the telescope ensures best performance. Fine adjustment is achieved with a solid 2 inch R&P focuser with 10:1 reduction. Blocking-filter is the B3400. The B3400 is good for solar imaging by cameras with very large sensor chips, and can also be used for visual observing. The B3400 blocking-filter is fix installed inside the 2 inch R&P focuser. Observing the starry night sky: The H-Alpha Etalon system can be removed from the telescope in a few easy steps thanks to its modular design. Then the 3-lens apochromatic refractor can be used as a normal telescope with 130mm aperture and 910mm focal length for observation and photography of the night sky. The FPL-51 triplet lens offers an outstandingly low colour aberration image. Common 2 inch star diagonals can be used at the R&P focuser of the telescope. Please note that the optionally available conversion kit 0551696 is absolutely necessary for the LS130MT version with B3400 blocking filter if the telescope is also to be used at night. The conversion kit is not required for the versions with B1200 and B1800. More applications: With additionally available accessories the LS130MT offers even more possibilities! - Double-Stack The LS130MT telescope can optionally be upgraded with the additionally available double-stack module LS130MT/DSII (item number 0551690). The DSII system is a internal double-stack module with Pressure-Tuner. Thereby a bandwidth of <0.5 Angstrom is achieved for H-alpha solar observation. Therefore much more details on the solar surface will become visible. - Solar observing in White-Light If the H-alpha unit has been removed, of course either a sun filter can be installed in front of the objective, or a Herschel-wedge at the focuser can be used to observe the sunspots in White-Light. - Solar observing in Ca-K wavelengthThe additionally available "LUNT Ca-K Filter Module for LS130MT" (item number 0551697) can be used on the LS130MT to observe and photograph super-granulation and other effects visible at this wavelength on the sun. This makes the LS130MT a completely universal usable apochromatic telescope of highest quality! FEATURES 3-lens APO refractor, FPL-51 Aperture: 130mm (no central obstruction) Focal length: 910mm Bandwidth: internal Etalon with <0.7 Angstrom Tuning: air pressure tuning system Pressure-Tuner Blocking filter: B3400 with 2 inch connection Focuser: R&P with 10:1 reduction Two tube-ring with handle Sol-Searcher installed inside handle Dovetail bar at GP-level for astronomical mounts Weight: 12.1kg Length with dew-shield: 95cm Length removed dew-shield: 80cm SCOPE OF DELIVERY LS130MT Multipurpose Telescope Pressure-TunerB3400 blocking filter installed inside focuserTube extension for using without H-alpha Etalon 2 inch R&P focuser with 10:1 reduction Tube rings with dovetail bar Transport case (92 x 42 x 35 cm) Instruction manual

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PULSAR DOMES 2.2 METRE OBSERVATORY GEN II SHORT HEIGHT
The Pulsar Observatory Dome provides a high quality, secure and practical housing for your telescope. Providing excellent weather protection for you and your telescope, it allows you to have your instrument ready for use at all times. Whether imaging or visual, having the convenience of a permanent set up adds greatly to your enjoyment of exploring the night sky. Ideal for up to 12" (30cm) aperture telescopes and a variety of installations, also ideal for societies, schools, etc. The Pulsar Observatory dome is sectional in design, and is delivered in kit form. Please Ring for details. The Pulsar Observatories 2.2 metre short height dome benefits from many advanced features.FEATURES Finest quality, weather proof GRP finishHigh quality locking system Simple design for self assembly Motorised dome rotation available Motorised dome shutters available Accessory storage bays availableAvailable in white (other colours - please call)Dimensions: Total Height approx 1.4 metres Dome Diameter approx 2.2 metresWall height 0.25 metres  Dome Aperture approx 0.6 metresAvailable in white - other colours e.g. green on request CUSTOMER REQUIREMENTS: Before you place the order of any Observatory Dome system please make sure that your department of planning and building inspection does agree. Probably you need a certain building permission.The customer will need to provide a level concrete base to ensure secure fixing and dome operation. Have a look to our installation guide which gives you an example for a suitable base dimension. Various upgrades and accessories are available. The 2.2 metre Observatory Dome is available in white - for other colours please call. We can also supply a steel pier, that will complete the permanent installation of your telescope, giving you more space within the dome than your existing tripod. We can also fabricate custom height piers to suit your requirements. VIDEO:  https://www.pulsarastro.com/video-guides-27-w.aspFAQ:  https://www.pulsarastro.com/drawings-and-guides-24-w.aspIMPORTANT NOTES:THIS PRODUCT CAN`T BE ORDERED ONLINE BUT BY PHONE CALL OR E-MAIL.  AFTER PLACING THE ORDER YOU WILL RECEIVE A SEPARATE SALES CONTRACT FROM BRESSER.THERE WILL BE A DELIVERY CHARGE FOR THE OBSERVATORY, PRICE ACCORDING TO LOCATION - PLEASE E-MAIL US OR RING FOR DETAILS. AVAILABLE FROM STOCK IN GERMANY OR FOR CUSTOMIZED PRODUCTS THE DELIVERY TIME IS: 6-8 WEEKS APPROX.Save cash money ! PULSAR domes are transported safely on oversized, individually manufactured pallets with special dimensions, which quickly make transport by freight forwarder expensive. Therefore, it would be possible for all customers to pick up their own PULSAR dome with their own transporter or trailer from BRESSER GmbH Rhede/Westphalia, GERMANY, by arrangement.

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EXPLORE SCIENTIFIC Sun Catcher Solar Filter for 150-165mm Refr.+8" SC
Explore Scientific's Sun Catcher Variable Large Aperture Solar Filters are available in many sizes to work on most telescopes from 60mm up to 10-inch Schmidt-Cassegrain and of course all Bresser and Explore Scientific Telescopes. The Solar Filter material being used is the new advanced 'Solarlite' Film manufactured by world famous Thousand Oaks Optical through years of research and development. 'Solarlite' a new solar film that has the optical quality of glass with the advantages of impregnated polymer. Perfect also for the solar astrophotographer. NOTE: All Explore Scientific Solar Equipment is rated ISO12312-2 supplied by Thousand Oaks Optical and approved for direct observation of the Sun . These solar filters are available in different sizes, the picture above shows three different sizes as an example. This is the solar filter with 165mm filter diameter. FEATURES Special objective filter for safe solar observations ISO12312-2 rated Field-stop diameter 165mm Fits to outer telescope tube diameter from 150 to 280mm Quick individual match with your telescope diameter Fast Setup - Easy Use SCOPE OF DELIVERY 1x Sun Catcher solar filter

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