BRESSER Extension Tube 37,5 mm for 2.5" HEXAFOC

​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

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

Giant binocular for observing the starry sky, nature and landscape. Observe the beauty of the starry sky at night and distant objects in nature during the day. Globular star clusters, glowing gas nebulae, the moon with its craters and even planets can be observed wonderfully on a clear night. But also all other distant things in nature and landscape, even ships and airplanes can be seen in detail. With the all-round binoculars of the EXPLORE SCIENTIFIC BT series, you can get up very close. Thanks to the large, light-gathering lenses and the professional coatings on all lens surfaces, these binoculars produce bright and brilliant images even at night and at twilight, providing a special viewing pleasure. The comfortable 45 degree viewing angle allows fatigue-free use, even when the binoculars are tilted upwards towards the zenith.  A large binocular can also be called a double refractor telescope Binoculars such as these can really be described as a double telescope.  In this configuration, the full light gathering power of one single telescope is available to each eye. Experience a whole new dimension of observing as a consequence. Objects are reproduced almost vividly in these binoculars and observing with both eyes is a very relaxing experience. Last but not least, this comfortable way of observation increases the recognition of the finest details (particularly in fainter deep sky targets) and effectively prevents eye fatigue. Extremely robust binoculars with magnesium housing, sealed and filled with nitrogen  The BT series binoculars are designed for tough outdoor use. The IPX6 sealed and nitrogen-filled design effectively prevents fogging of the internal optics even under difficult weather conditions. The very light magnesium housing saves weight and makes it easy to handle. Two EXPLORE SCIENTIFIC 20mm eyepieces of the 62 degree LER series already included. EXPLORE SCIENTIFIC is an established manufacturer of extremely high-quality eyepieces in the astronomy scene. An optical system is only as good as its weakest component. Therefore we have decided to deliver these giant binoculars with a pair of quality eyepieces of the 62 degree LER series. With an apparent field of view of 62 degrees and a focal length of 20mm, the BT-120 binoculars produce a 33x magnification. Thus these wide angle eyepieces offer a very good overview (field of view 1.8 degrees) at moderate magnification. The large interpupillary distance of these LER (long eye relief) eyepieces of 15mm and soft silicone eyecups, which can be turned inside out, also guarantee a comfortable and relaxed view. For astronomy, a flat and sharp image field is advantageous and offers a particularly impressive viewing experience even during the day. Due to the waterproof design and the argon filling, these eyepieces are absolutely durable and easy to clean. Interchangeable eyepieces with 1.25 inch / 31.7mm plug-in diameter Adjust the magnification and field of view to your individual needs and choose from a wide range of available eyepieces. All eyepiece types with a plug-in diameter of 1.25 inch / 31.7mm can be used with the binoculars of the BT series. Especially recommended are EXPLORE SCIENTIFIC eyepieces of the 62 and 82 degree series with focal lengths from 8 to 26mm (see item No. 02188xx and 02196xx). The magnification can be varied from 25x to 75x (focal length binoculars : focal length eyepiece = magnification). The eyepieces are held in the binoculars by a precise brass compression ring clamp and guarantee a tilt free position.  Use of colour and nebula filters for astronomical observations Increase the contrast and visibility of objects and details by screwing the corresponding filters directly into the thread of the eyepiece sleeves. The use of colour and nebula filters must of course always be done in pairs. Suitable are all EXPLORE SCIENTIFIC screw filters with 1.25inch / 31.7mm diameter (see item No. 03102xx)  Comfortable 45 degree view and helical single focus The 45-degree viewing angle allows a relaxed observation position even when the binoculars are tilted strongly. Also the individual interpupillary distance can be adjusted in a range from 54 to 76mm. With the fine helical individual focusing, precise focusing is achieved effortlessly. Extendable dew caps The integrated dew caps can be removed in high humidity and cold conditions. This avoids fogging of the outer objective lenses and effectively shields additional control light coming in from the side. Integrated carrying handle A metal carrying handle located at the center of gravity facilitates transport and ensures a secure hold during tripod assembly. Suitable tripods and tripod connectionWhen using these large binoculars, a sturdy photo tripod with an appropriate load capacity is highly recommended. The connection is made via two 1/4 inch or one 3/8 inch threaded holes (standard photo tripod thread) in the tripod adapter of the binoculars. The ideal solution is to use the optional available EXPLORE SCIENTIFIC U-Mount with field tripod (item No. 0114300). This is specially designed for the large binoculars of the BT series and carries these binoculars absolutely securely. The excellent support mechanism, with adjustable friction in both axes allows easy moving and tracking. The binocular position is kept stable depending on the adjusted friction intensity. Vibrations are reduced to a minimum by the massive construction of the U-Mount and the large stainless steel tripod. Even at high magnification there are no discernable vibrations and this allows the finest details to be observed in a chosen target.FEATURES Large binoculars for observing the starry sky, nature and landscape Observe globular star clusters, glowing gas nebulae, the moon with its craters and even planets Also wild animals, ships and airplanes can be seen in detail Highly light gathering lenses produce a bright and high-contrast image All-round binoculars, but especially suitable in twilight and at night The comfortable 45 degree viewing angle allows fatigue-free use One complete lens telescope with the full light gathering power is available per eye Extremely robust binoculars with magnesium housing, sealed and filled with nitrogen Two EXPLORE SCIENTIFIC 20mm eyepieces of the 62 degree LER series already included 33x magnification and an apparent field of view of 62 degrees, true visible field of 1,8 degreesLarge interpupillary distance of 15mm to the eyepiece lens for comfortable viewing Eyepieces interchangeable and with standardized plug-in diameter of 1.25 inch / 31.7mm The magnification can be adjusted with optional eyepieces from 25x to 75x Precise brass eyepiece compression ring clamps for tilt-free fitColor and nebula filters can be used for astronomical observations Extendable dew caps prevent fogging of the outer objective lenses and stray light Integrated carrying handle facilitates transport and mounting on the tripod Tripod connection via two 1/4 inch or one 3/8 inch threaded holes (standard photo tripod thread) Tripod recommendation: EXPLORE SCIENTIFIC U-mount with field tripod (Art.No. 0114300) Objective type: Air spaced achromatic lens (2 elements/ 1 group) Coating: full multilayer coating on all optical surfaces Aperture, focal length and aperture ratio: 120mm / 660mm / F=5.5 Sealed to IPX6 standard and nitrogen filled: yes / yes Close focus distance: 35 meters Eyepiece mount diameter: 1.25'' / 31.7mm Adjustable interpupillary distance: 54 to 76 mm Helical single focus: yes BAK-4 prism system for a bright and high-contrast imageDimensions and weight of binocular: 654 x 290 x 156mm, 8.3kg Housing colour of binocular:  white What's included Giant binocular with carrying handle (without tripod)Eyepieces ES 20mm 62 degrees LER Series (2pcs)Precisely fitting foam insert for transport Dust covers for objectives and eyepiece sockets Instruction manual

Are you having trouble focusing your eyepiece or camera? Then use this BRESSER 25 mm extension sleeve to increase the distance between the 2.5 inch HEXAFOC eyepiece extension and the eyepiece or camera. The extension sleeve has an M68x0.75 mm internal and external thread and can therefore be screwed directly onto the HEXAFOC draw tube.SPECIFICATIONSIncreases the distance to the eyepiece/camera Suitable for 2.5 inch HEXAFOC Optical length: 25 mm Internal and external thread: M68x0,75 mmInside black matt coated Material: aluminium, black anodized SCOPE OF DELIVERYExtension sleeve 25 mm (1 piece)