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BRESSER Extension Tube 25 mm for 2.5" HEXAFOC

With BRESSER, you can enjoy a smooth introduction to the vast world of astronomy. Our detailed information ("Telescope Guide") provides valuable tips for beginners—but even experienced astronomers can use the information we provide (e.g., tables for the geographical latitude of all major world cities) as a reference.

Here is the table of contents of the comprehensive BRESSER Telescope Guide:

Sky Guides by Bresser

The Sky Guide provides comprehensive information on constellations, planetary positions, and astronomical events – perfect for planning your observations and delving deeper into astronomy.
Visit the guide directly here to make the most of your observations!

Product and safety instructions


Manufacturer: 
Bresser GmbH, Gutenbergstraße 2, 46414 Rhede

Contact: 
www.bresser.de


Warning notes
  • General warning instructions DANGER! RISK of bodily injury! Never look directly at the sun or near the sun through this device. There is a risk of blindness! Sharp-edged and pointed tools are often used with this device. Therefore, store this device and all accessories and tools in a place inaccessible to children. There is a RISK of injury! Children may 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. NOTE! Do not dismantle the device! In case of a defect, contact your dealer. They will contact the service center and may send the device in for repair. PRIVACY PROTECTION! The telescope is intended for private use. Respect the privacy of others – for example, do not use this device to look into apartments!
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BRESSER Extension Tube 37,5 mm for 2.5" HEXAFOC
Are you having trouble focusing your eyepiece or camera? Then use this 37.5 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/cameraSuitable for 2.5 inch HEXAFOCOptical length: 37,5 mmInternal and external thread: M68x0,75 mmInside black matt coatedMaterial: aluminium, black anodizedSCOPE OF DELIVERYExtension sleeve 37,5 mm (1 piece)

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EXPLORE SCIENTIFIC 2" Variable Polarizing Filter
Universally usable variable polarizing filter with a  2" 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 2.0" 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 housing2.0" filter thread on both sidesSCOPE OF DELIVERYpolarizing filterprotective box

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EXPLORE SCIENTIFIC 3" 0.7x Reducer/corrector
The EXPLORE SCIENTIFIC 3" 0.7x Reducer/corrector, reduces a compatible telescope's focal length by a factor of 0.7x (for around f/8) and 0.8x (for around f/10) respectively. The reducer/corrector not only reduces the focal length but also flattens the field. Although originally developed for the Explore Scientific ED-APOs 127mm and 152mm, the reducer can be used with many systems - for example with the Explore Scientific ED-APOs 102mm and 165mm (please note, this will not work on the Explore Scientific 80mm ED Apo refractors though). With certain telescope focal lengths, a slight restriction of the correction at the edge of the image field can be expected when using full-frame sensors. This unit comes with 3" barrel adaptor for direct focuser thread M54x0.75 (the standard focuser thread of the Explore Scientific Essential series of ED Apos) and T2 camera adaptor. This reducer/corrector features a free aperture of 65mm, so that it can be used even with cameras that have a large sensor - if the telescope allows for this. Note: As previously mentioned, this Reducer/corrector comes with a screw on ring, which fits the standard focuser thread of the Explore Scientific Essential series of ED Apos. For telescopes which are equipped with the 2.5" HEX Focuser, the optional screw-on adapter part no: 0510366 is needed. Other telescopes, not in the Explore Scientific range, with standard 2" push-fit focusers will need the Explore Scientific 2" Adaptor for 3" Corrector - part no: 0510364 to get this reducer correctly fitted. SPECIFICATIONS Reduces the focal length by 0.7x at f/8 Flattens the field for astrophotography Developed for ED127 und ED152 APO telescopes Also fits Explore Scientific ED102 and ED165 telescopes - and others Free aperture: 65mm Inner thread for telescope adaption: M76x0.75mm Outer thread for camera adaption: M72x0.75mm 3" focuser barrel adaptor included Adaptor for Explore Scientific focuser M54x0.75mm included T2 camera adaptor M42x0.75mm included Diameter: 78.5mm; length: 100mm Length without adaptors: 52mm Weight without adaptors: 530g What's Included Reducer/Flattener 3" focuser barrel adaptor Adaptor for Focuser M54x0.75mm T2 camera adaptor M42x0.75mm Dust caps

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EXPLORE SCIENTIFIC Hexafoc 2.5 adaptor for 3" 0.7x Corrector
This adaptor enables you to connect the 0510360 0.7x focal reducer/field flattner to telescopes that feature the 2.5" Hexafoc. The big inner diameter of the 2.5" Hexafoc is fully utilised with this adaptor to avoid vignetting.What's Included1x Hexafoc 2.5 adaptor for 3" 0.7x Corrector ring

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EXPLORE SCIENTIFIC 68° Ar Eyepiece 16mm (1,25")
With the introduction of the 68° Series we are pleased to make two important improvements in eyepiece manufacture, the first being 15 layer Enhanced Multi-layer Deposition (EMD™) coatings on all glass-to-air surfaces to gain maximum contrast, and waterproofing the eyepiece with the use of Argon gas purging instead of standard Nitrogen gas. Although Nitrogen is a fine choice that will last for many years, Argon is a larger molecule that maintains its protective properties over a wider range of temperatures, and is even more resistant to diffusion thereby further extending the protective waterproof environment of the eyepiece body. Through computer-optimized design, a careful selection of optical glasses, and enhanced multi-layer deposition coatings, the Explore Scientific 68° Series™ eyepieces produce long eye-relief and ensure high image-correction, a flat field, and high contrast across the entire image field. An excellent choice for those who make extended visual studies of detail with subtle variations of brightness, and for those who must wear glasses while observing. All 68° Series eyepieces are fully EMD (Enhanced Multi-Layer Deposition) coated and edge-blackened to produce superior contrast.

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BRESSER Gear-Set 1:8 Messier Hexfoc
For astrophotography it is essential to achieve the correct focus point with great precision. With the 1:8 Gear set precision focussing is easy. The gear set can be installed easily without difficulties and upgrades a 2,5" Hexafoc to a full 2,5" Hexafoc DeLuxe.Installation video:  https://www.youtube.com/watch?v=RCnsn2o-B94&t=144s

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BRESSER Polaris-I 102/460 EQ3 Refractor Telescope with Smartphone Adapter & Solar Filter
The view of the night sky holds countless fascinating sights in store for us. The BRESSER Polaris-I 102/460 EQ3 lens telescope comes with everything you need for a quick and easy start in astronomy: an astronomical lens telescope with 102 mm aperture and 460 mm focal length, an equatorial mount, a tripod and a wide range of accessories. The system is extremely easy to handle - perfect for newcomers to the exciting hobby of astronomy. Moreover, due to its compact dimensions, the entry-level telescope is ideally suited as a travel telescope. So find the perfect observation site and enjoy an exciting ''walk'' through the Milky Way. Classic telescope for a new generation of stargazers – the telescope Children and beginners in particular benefit from the classic design of this lens telescope, which is also called an achromatic refractor according to Fraunhofer. This is mainly due to its easy handling – ideal for your fist steps in celestial observation. The entry-level telescope owes its good imaging properties to the optics’ modern, precise coating. The 102 mm aperture already collects a lot of light from the celestial objects. But it is due to the very short focal ratio (ratio of 102 mm aperture and 460 mm focal length) of about 1 to 4.5 (F/4.5) that you can enjoy an extra-bright image. Another advantage of the combination of short focal length and fast focal ratio: the beginner's telescope shows you the details in the Milky Way and extended gas nebulae such as the North America Nebula NGC 7000 particularly impressively. This makes a ''trip'' through the Milky Way with low magnification so much fun. However, the telescope will also give you a lot of pleasure while travelling on Earth, because it is very compact and thus perfect as a travel telescope. And what about the magnification? Here, too, the aperture of 102 mm shows its effect: It gives the telescope a resolving power that easily allows magnifications of up to about 200x with sharp images. From a purely technical point of view, this is by no means the limit – with the included accessories, you can theoretically magnify up to 345x. The image sharpness can slowly decrease with increasing magnification, though. However, the degree of magnification achievable does not only depend on your telescope. The air turbulence in the atmosphere (seeing conditions) also influences your astronomical observations. Set up, align, start marvelling – mount and tripod Found the perfect location for your observations? Then attach the telescope tube to the eight-adjustable aluminium tripod with equatorial mount and off you go. The special advantage of equatorial mounts: Unlike with an azimuthal mount, you don't need to move both axes at the same time. Instead, you align one axis parallel to the Earth's axis by pointing it approximately at the polar star. Then you simply track the movement of the celestial bodies just on this one axis. Because you move the axes via two flexible shafts with fine adjustment, you can adjust and track the beginner's telescope very precisely and comfortably. And for quick access to all your accessories, simply place them on the tray between the tripod legs.Keep track of things automatically: For this telescope’s equatorial EQ-3 mount, the tracking motor with item number 4951400 is available as an optional accessory. This eliminates the need to manually track a celestial object set in the telescope. When this motor is installed at the mount, it automatically tracks the celestial object, keeping it in the field of view of the eyepiece. This makes observing the night sky even more comfortable! Must-haves for star observation – the accessories In order for you to start stargazing right away, the astronomy set comes with many accessories. With the LED viewfinder, you can easily keep track of the sky. Just install the viewfinder parallel to the actual telescope and it projects a red dot onto a small ground-glass screen. When you look through it, this dot appears to be floating in front of the sky. Not just anywhere, but exactly at the point at which your telescope aperture is currently pointing. This allows you to align your telescope more precisely and find the celestial objects you have chosen for your night-time exploration much more easily. As with everything else, a change of perspective is always fun. Therefore, the two eyepieces (4 mm and 20 mm) allow you to view the objects in different magnifications – and thus enjoy completely different views. You want to see even more details? Then triple the magnification of the eyepieces with the 3x Barlow lens. The telescope for beginners is also flexible when it comes to upgrades: the diameter of the sockets is 31.7 mm (1.25 inches), which is an international standard that applies to all manufacturers. So you can choose from a large variety of additionally available eyepieces. In order for you to explore the universe with ease, the 90-degree star diagonal mirror always offers a comfortable view into the beginner’s telescope. Even if the telescope is pointed vertically upwards into the sky, you simply look in from the side – and just enjoy the view. But it is not only at night that the sky attracts our attention with spectacular highlights. In the daytime sky, our nearest star is particularly worth seeing. You can observe it completely safely using the solar filter. You will be amazed once you take a closer look at the sunspots and the granulation on the Sun. CAUTION: Never point the telescope at the Sun without the solar filter! Capture your favourite moments of sky observation. You can easily take your first steps in astrophotography by using the smartphone camera adapter – for impressive snapshots of the Sun and Moon, for example. Set off on your very own voyage of discovery to the Sun, Moon and through the Milky Way – with the BRESSER Polaris-I 102/460 EQ3 refractor telescope. FEATURES Telescope for beginners with 102 mm aperture and 460 mm focal length Achromatic refractor type Fraunhofer Ideal for observing the Milky Way and extended gas nebulae at low magnifications Height-adjustable tripod with equatorial EQ3 mount Easy to use, very good for beginners Focal ratio F/4.5, therefore very fast and bright image Very compact, therefore good as a travel telescope 50.8 mm (2 inch) focuser with adapter to 31.7 mm (1.25 inch) Two eyepieces and one Barlow lens with 31.7 mm (1.25 inch) sockets for different magnifications Safe solar observation with the included solar filter Entry into astrophotography with smartphone camera adapter SCOPE OF DELIVERY Lens telescope Aluminium tripod Equatorial EQ3 mount Eyepieces: 4 mm and 20 mm (1.25 inch sockets) Barlow lens 3x (1.25 inch socket) Star diagonal mirror LED illuminated dot finder Solar filter Smartphone camera adapter Accessory tray Astronomy software download Instruction manual

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BRESSER Extension Tube 37,5 mm for 2.5" HEXAFOC
Are you having trouble focusing your eyepiece or camera? Then use this 37.5 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/cameraSuitable for 2.5 inch HEXAFOCOptical length: 37,5 mmInternal and external thread: M68x0,75 mmInside black matt coatedMaterial: aluminium, black anodizedSCOPE OF DELIVERYExtension sleeve 37,5 mm (1 piece)

Available

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BRESSER Extension Tube 20 mm for 2.0" R&P Focuser
Are you having trouble focusing your eyepiece or camera? Then use this BRESSER 20 mm extension sleeve to increase the distance between the 2.0 inch Rack & Pinion focuser and the eyepiece or camera. The extension sleeve has an M54x0.75 mm internal and external thread and can therefore be screwed directly onto the HEXAFOC draw tube. Suitable for the EXPLORE SCIENTIFIC ED APO Essential series, among others.FEATURESIncreases the distance to the eyepiece/camera Suitable for 2.0 inch R&P focuser Optical length: 20 mm Internal and external thread: M54x0,75 mmInside black matt coated Material: aluminium, black anodized SCOPE OF DELIVERYExtension sleeve 20 mm (1 piece)

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BRESSER Extension Tube 37.5 mm for 2.0" R&P Focuser
Are you having trouble focusing your eyepiece or camera? Then use this BRESSER 37.5 mm extension sleeve to increase the distance between the 2.0 inch Rack & Pinion focuser and the eyepiece or camera. The extension sleeve has an M54x0.75 mm internal and external thread and can therefore be screwed directly onto the HEXAFOC draw tube. Suitable for the EXPLORE SCIENTIFIC ED APO Essential series, among others.FEATURESIncreases the distance to the eyepiece/camera Suitable for 2.0 inch R&P focuser Optical length: 37.5 mm Internal and external thread: M54x0,75 mmInside black, matt coated Material: aluminium, black anodized SCOPE OF DELIVERYExtension sleeve 37.5 mm (1 piece)

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BRESSER Variable Adapter
The BRESSER camera adapter is the ideal connecting piece between your 35 mm SLR camera or DSLR and your telescope. The adapter is suitable for 1.25" eyepieces with a larger housing diameter of up to 55 mm. Please note, this adapter will be suitable for most Refractors and Cassegrain designs, but may not be suitable for use with all Newtonian designs of telescopes, due to the comparatively short travel of focus in some Newtonians. Please check with us if you'd like further advice regarding your particular telescope.FEATURESvariable camera adapterfor eyepiece projection and prime focusincludes a short prime focus adapter from 1.25" to T2 threadsuitable for 1.25" eyepieces up to 55mm housing diameter barrel diameter: 31.7mm (1.25")WHAT'S INCLUDEDvariable camera adapter

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BRESSER Gear-Set 1:8 Messier Hexfoc
For astrophotography it is essential to achieve the correct focus point with great precision. With the 1:8 Gear set precision focussing is easy. The gear set can be installed easily without difficulties and upgrades a 2,5" Hexafoc to a full 2,5" Hexafoc DeLuxe.Installation video:  https://www.youtube.com/watch?v=RCnsn2o-B94&t=144s

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BRESSER T2 Extension Tube Set
Set of 5 extension tubes with T2 thread on both sides for exact distances and secure hold of cameras for astrophotography. Also comes with SC to T2 thread adapter.In astrophotography, most cameras are connected to a telescope via a T2 thread (M42x0.75), the most popular international standard. However, in many cases, T2 and T2-ring adapters for connecting telescope focusers to a camera are not sufficient, as specific distances must also be observed. This is especially important when using correctors, reducers or flatteners. This extension tube set, which consists of 5 mm, 7.5 mm, 10 mm, 15 mm and 30 mm tubes, will allow you to obtain almost any distance using the corresponding combination. Each tube has a T2 interior thread on one side and a T2 exterior thread on the other side.Most telescopes either include a T2 thread adapter, or the eyepiece can be used with a simple T2 thread adapter with a 2” plug-in diameter (item no. 0510365).However, Maksutov-Cassegrain, Schmidt-Cassegrain, ACF or Ritchey–Chrétien telescopes may use a so-called SC thread. To allow you to use this extension tube set with these telescopes, the set also includes an SD to T2 thread adapter.FEATURES5 T2 tubes with lengths from 5 mm to 30 mmCombination of tubes allows you to obtain distances of 5 mm to 67.5 mmFor exact camera distances in astrophotographyDELIVERY CONTENT5x T2 extension tubes (5/7.5/10/15/30 mm)1x SC to T2 thread adapter

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