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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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BRESSER Messier 8x50 Viewfinder
BRESSER Messier 8x50 Viewing finder scope with mount and integrated illumination. Finder slot included.FEATUREShigh-quality workmanshipintegrated illuminationeyepiece with reticleSCOPE OF DELIVERYviewfindermountviewfinder shoeprotective caps

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EXPLORE SCIENTIFIC 2" O-III Nebula Filter
One of the most important obstacles for the exploration of the night sky is the brightening of the night sky by artificial lights, such as streetlights. The night sky is not really dark in the vicinity of towns or cities, which reduces the visibility of objects beyond the solar systems enormously. Depending on the type of the celestial object it is possible to increase the contrast dramatically by blocking the annoying artificial light. The EXPLORE SCIENTIFIC O-III filter uses a characteristic property of the so called emission nebulae. Those objects glow in special colours, the so called emission lines. Those emission lines are linked to chemical elements - in this case oxygen. The EXPLORE SCIENTIFIC O-III nebula filter blocks all other colours (and thereby nearly all of the artificial light) and only the two emission lines of the oxygen can pass the filter. The result is astonishing: suddenly nebulae are visible at locations that were completely empty without filters. In suburban skies for example the veil nebula NGC 6992 is almost not visible with a 200mm telescope. By using this filter you can see the nebula and its structures without problems. A must for every visual observer. The EXPLORE SCIENTIFIC nebula filters come with a individual test certificate - your guarantee to receive a premium filter.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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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 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 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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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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BRESSER Extension tube 2"/35mm
Extension tube with 2" plug diameter and an extension factor of 35mm. A ring clamp ensures an optimal attachement of 2" accessories. The blackened and ridged inside effectively prevents reflections. Also a 2" filter thread is inside.

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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 Barlow Lens 2x 31.8mm/1.25"
With the usage of barlow lenses, you can extend the equivalent focal length of telescopes and hence increase the magnification of your observed targets. Subsequently, you can use lower power eyepieces in Barlows to act as much more powerful eyepieces, but retain the larger ocular size and more comfortable viewing that comes with lower power eyepiece designs.Due to their two lens design, these Barlow lenses provide a brilliant image quality for the whole visual field and are suitable for observations and photography.  The black coloured Barlow element cell in this BRESSER Barlow Lens 2x 31.8mm/1.25," can be unscrewed and has the same thread as 1.25" filters, allowing it to be mounted in 1.25" eyepieces, t-adapters and other accessories, giving you flexibility of use and the ability to vary magnification in different accessories.  For instance, the black Barlow cell screwed into the average length nosepiece of a standard push fit t-adapter will give around 1.6x magnification on an attached DSLR.  This can be very useful when trying to get to photographic focus with some Newtonians and Solar Telescopes, which lack the necessary amount of in focus travel to get a camera to a prime focus position.FEATURESsuitable for observations and photographydoubling of the focal lengthtwo lens designfully multi-coatedWHAT'S INCLUDEDBarlow lens (1pc)

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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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