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Vixen SD Flattener HD Kit

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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 suffocation! Improper use of this product can result in suffocation, especially for children. Therefore, carefully observe the following safety instructions. Keep packaging materials (plastic bags, rubber bands, etc.) away from children! There is a risk of suffocation! Keep cords, ribbons, and similar materials away from children! They could accidentally strangle themselves and suffocate! NOTE Risk of material damage! Improper handling can damage the device and/or accessories. Therefore, only use the device according to the following safety instructions. Do not dismantle the device! In the case of a defect, contact your dealer. They will contact the service center and may send the device in for repair.
  • 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

Vixen universal T2 focal adapter, 60 mm

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€54.00*
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Vixen Wide Photo Adapter 60DX for Nikon
The Wide Photo Adapter 60DX connects your Nikon DSLR camera to your telescope via a 60 mm thread. Thanks to the use of new materials and an improved design, Vixen was able to significantly improve the precision and load capacity compared with conventional adapters. The adapter's large interior diameter prevents shadows at the edges of the image when using a full-frame DSLR camera.FEATURESIncreased material strength for additional stability6 screws hold the camera in position (compared with 4 on most conventional adapters)Screw tips with Delrin inserts prevents the camera from tilting and minimizes distortion.Large interior diameter prevents shadowingBlack interior prevents scattered lightCompatible with 60 mm accessories when the camera adapter is removed2 screw sets (L and S) prevent scratches on the camera housing2 screw sets for adjusting the rotation resistanceDELIVERY CONTENTVixen Wide Photo Adapter 60DX for Nikon cameras2 screw sets (L and S)

Available

€127.00* €159.00* (20.13% saved)
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Vixen T2 ring for Nikon
T2 rings are used as a connecting piece between the camera adapter and the camera. Please note that each camera type requires a different T-ring.FEATUREST2 adapter ring for Nikon camerasAdapts the camera to telescopes and microscopesWeight: 22 gPACKAGE CONTENTSVixen T2 ring for Nikon

Available

€22.00* €28.00* (21.43% saved)
Vixen T-ring for Canon EOS
T-rings are used as a connecting piece between the camera adapter and the camera. Please note that each camera type requires a different T-ring.FEATURESVixen T-ring for Canon EOS camerasConnects a camera adapter to the cameraFor microscopes, telescopes and T2 lensesWeight: 52 gPACKAGE CONTENTSVixen T-ring for Canon EOS

Available

€28.00*
Vixen T-Ring for Sony E Cameras
This T2 ring allows you to use your Sony camera on a telescope or microscope with a T2 thread.Depending on the mode, you may require an additional camera adapter.FEATUREST-2 ring for connecting an SLR cameraDesigned for Sony EWeight: 113 gDELIVERY CONTENTT-2 Ring Sony E

Currently unavailable

€55.00*
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Vixen T-Ring - Four Thirds
Connects a Four Thirds camera to your telescope or microscope.A camera adapter is required for this purposeWeight: 58 gDELIVERY CONTENTVixen T-ring - Four Thirds

Available

€22.00* €28.00* (21.43% saved)
Vixen Micro 4/3 T-ring
T-rings are used as a connecting piece between the camera adapter and the camera. Please note that each camera type requires a different T-ring.FEATURESMicro 4/3 T-ringFor telescopes and microscopesWeight: 110 gPACKAGE CONTENTSMicro 4/3 T-ring

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€55.00*
Vixen SG-L02 Headlamp red-light white-light
The perfect LED head torch for nighttime observations! Adjusting your eyes to the dark surroundings is very important when making astronomical observations. In dark areas, it is very difficult to use astronomical equipment without a suitable light. With normal lights, however, the light intensity is more important than protecting your eyes against bright light. Using these lights at night makes your pupils contract, which can make it difficult for your eyes to readjust to the darkness. The SG-L01, our first astronomy LED lamp, featured a built-in red LED that provided a solution to this problem. However, the red light did not offer optimal visibility. On our new astronomy LED light, the SG-L02, the LED lights produce warm light to improve visibility. They also ensure that your eyes stay adapted to the dark. The LEDs do not emit light in the sensitive range of 555 nm. The brightness of the white light can be adjusted between 3 and 42 lumen, while the red light can be adjusted between 0.28 and 7.62 lumen. FEATURES Dimmable red light ensures that your eyes stay adapted to the dark Built-in rechargeable battery, charges via USB Waterproof design LED colour can be switched from red to white 0.28 to 7.62 lumen for red light 3 to 42 lumen for white light Dimensions: 41 mm x 33 mm x 30 mm Weight: 29 g DELIVERY CONTENT SG-L02 head torch Strap (size S) Strap (size L) Pocket clip Cable for charging the battery (USB-A plug to USB Micro-B plug)

Available

€69.00*
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Vixen SD103S apochromatic Refractor
A new apochromatic refractor with high performance Super-ED glass (= SD). The FPL53 glass reproduces an extremely clear and sharp image by an exceptionally high degree of elimination of residual chromatic aberrations. The advantage of these SD refractors is their short length and low weight. The SD glass is designed to bring all beams of violet, red, blue, yellow and green very precisely together on the same plane. The special lens material, reduces chromatic aberration across all colors. In combination with the new optional SD Reducer HD Kit or SD Flattener HD, these refractors allow illumination with a 44mm image circle for full format SLR cameras. FEATURES Lens diameter: 103mm Type of coating: Multi-coated Focal length: 795 mm (f7.7) Resolution: 1.13 arc seconds Visual limit value: 11.8 mag Max. magnification: 206x Tube length: 810mm Tube diameter: 115mm Tube weight: 5,4kg Viewfinder telescope: 7x50 with illumination unit Adapter 7.0 degrees FOV included Connections/adapters: thread 60mm and 31.7mm for T-ring Eyepiece adapter: 50.8mm (2 inches) and 31.7mm (1.25 inches)Backfocus without Reducer: 150,4 mmBackfocus with Reducer: 63,5 mmFlip mirror included SCOPE OF DELIVERY Optical Tube Tube rings with carrying handle GP dovetail adapter Flip mirror Dust covers

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€1,679.00* €2,099.00* (20.01% saved)
Vixen Reducer HD
Above-average contrast The Reducer HD features the optical coating that was developed by Vixen for our high-end VSD100F3.8 astrograph. The AS coating provides light transmission of up to 99.9% per lens surface. The special matte surface in the interior also minimizes ghosting, light loss and lens flares. Reducer HD in combination with SD telescopes The Reducer HD can be used on telescopes from the SD series (SD81S, SD103S and SD113S) with the SD Flattener HD Kit (item #37246) . The Reducer HD reduces the focal length by a factor of 0.79x (f/7.7 to f/6.1) and delivers a razor sharp image over the entire 44 mm image sensor surface on DSLR cameras. Reducer HD in combination with AX103S and VC200L telescopes In addition to the SD telescopes, the Reducer SD is also compatible with the AX103S and VC200L telescopes. With these telescopes, the focal length is reduced by a factor of 0.77x.FEATURESUp to 99.9% light transmission per lens surfaceReduces the focal length by a factor of 0.79xAlso suitable for full-frame DSLR camerasFor the ED/SD 81S, 103S, 115SAS coating with light transmission of up to 99.9% DELIVERY CONTENTVixen Reducer HDDust caps

Currently unavailable

€349.00*
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Vixen Reducer HD
Above-average contrast The Reducer HD features the optical coating that was developed by Vixen for our high-end VSD100F3.8 astrograph. The AS coating provides light transmission of up to 99.9% per lens surface. The special matte surface in the interior also minimizes ghosting, light loss and lens flares. Reducer HD in combination with SD telescopes The Reducer HD can be used on telescopes from the SD series (SD81S, SD103S and SD113S) with the SD Flattener HD Kit (item #37246) . The Reducer HD reduces the focal length by a factor of 0.79x (f/7.7 to f/6.1) and delivers a razor sharp image over the entire 44 mm image sensor surface on DSLR cameras. Reducer HD in combination with AX103S and VC200L telescopes In addition to the SD telescopes, the Reducer SD is also compatible with the AX103S and VC200L telescopes. With these telescopes, the focal length is reduced by a factor of 0.77x.FEATURESUp to 99.9% light transmission per lens surfaceReduces the focal length by a factor of 0.79xAlso suitable for full-frame DSLR camerasFor the ED/SD 81S, 103S, 115SAS coating with light transmission of up to 99.9% DELIVERY CONTENTVixen Reducer HDDust caps

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€349.00*
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EXPLORE SCIENTIFIC Zero X Field Flattener 2''/M48 for ED80, ED102 and ED127 APO
Field flattener without reduction factor for Explore Scientific ED80 , ED102 and ED127 APO Refractors Correction for up to full-frame camera sensors (24x36mm) How to use the Zero X field flattener with M48 thread connectionFEATURESField flattener for Explore Scientific ED80, ED102 and ED127 APO telescopesRemoves field curvature from telescopesProduces round stars even at the edge of the image fieldImage sharpness at the edge is drastically increasedA clear benefit for the whole image aestheticsCorrection of field curvature for up to full-frame camera sensors (24x36 mm)Image field flattener without reduction factorOn the telescope side with 2 inch (50.8 mm) plug-in connection and M48x0.75mm filter threadCamera side with large M48 threaded connectorWorking distance of 55 mm between field flattener and camera sensorFor telescopes with a focal length of approx. 480 to 952 mmOptimised for telescopes with focal ratios from F=6.0 to F=7.5Can also be used for various other APOsFully multi-coating on all lens surfacesHousing made of lightweight aluminium, black anodisedAluminium dust cap for M48 threadSCOPE OF DELIVERYZero X field flattener (1 piece)Dust caps

Available

€179.00*
Vixen Dovetail Slide Bar M
The Vixen dovetail bar M is designed to balance an optical telescope tube. This is achieved by securing the bar to the tube clamps.FEATURES Dimensions: 211 mm x 50 mm x 21 mm Weight: 270 g / 9.52 ozDELIVERY CONTENTVixen dovetail bar MToolMounting screws

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€49.00*
Vixen VSD90ss Astrograph
Fast 90 mm high-performance astrograph for demanding astrophotographers and observers with 5 lens elements in 5 groups. Due to the complex optical structure with five lens groups and five elements (quintuplet), including two SD (Super ED) lenses and an ED lens (Extra-low Dispersion) , a virtually aberration-free optical system was created. This revolutionary astrograph is compatible with a full-frame digital DSLR or an even larger 44x33 mm camera. The 90 mm astrograph with fast aperture ratio delivers exceptionally sharp, high-contrast and small point stars from the centre to the corners of the field of view. In addition, it is also ideal for visual observation with a very large field of view but also for planetary observation with high magnification. The VSD90ss is designed so that there is a "long peak range" in the adjustment accuracy of the sharpness, so that photographers can always achieve satisfactory results in astrophotography. Even if the focus is not quite precise, round and sharp stars are still shown throughout the entire image field. Illumination without vignetting In most cases, an astrograph also produces optical vignetting (a gradual decrease in light rays towards the edge of the image) This is mainly caused by rear lenses being shaded by the front lenses. Because of this darkening, it is relatively normal for the photographer to have to further edit the image after taking the picture and also have to do some additional so-called flats before taking the picture. To solve this problem, the VSD90ss uses wide aperture lenses in the rear elements, securing over 90 % of the light volume at the edge of the 60 mm image circle. Since the light intensity is uniform throughout the entire image field of the VSD90ss, there is no need for complex technology to prevent edge darkening. The VSD90ss is coated with the most modern coatings of extremely high reflectivity. These coatings have been specifically developed to optimize the properties of each individual lens element without degrading contrast and light intensity across multiple lenses. Numerous gradations of light bring beautiful point-like stars into the image field The low optical vignetting ensures sufficient illumination and thus eliminates the asymmetric flare caused by bright, diffraction-limited stars. It prevents stars at the edge of the 60 mm image circle from exhibiting deformations such as comets, astigmatism or coma. Since the illumination of the image field is relatively similar from the center to the edge of the image, you can expect excellent star imaging. Please note: *Depending on the recording system used, mechanical vignetting can still occur due to the camera body or incorrect adapters. 96.7% Strehl for impressive visual observations The VSD90ss offers a flattened large field of view with a low magnification wide angle eyepiece. Even with a high-quality wide-field eyepiece with a large field of view, you can get sharp images of stars in the entire field of view when visually observing! In the centre of the field of view, a Strehl intensity of an impressive 96.7% is achieved at visible wavelengths. This Strehl ratio exceeds that of the SD81SII apochromat at 95.7%, which is known for its excellent optical properties, and this also works excellently when observing the moon and planets at high magnification. The versatile large and stable focuser The VSD90ss has a large focuser with a diameter of 87.5 mm to make optimal use of the large illumination field of 60 mm. With the large extension that is compatible with many accessories, it is perfect for astrophotography up to large format or 35 mm full frame DSLR cameras. Thanks to its precise manufacturing, it is also suitable for very heavy cameras without tipping. The precision locking lever of the eyepiece extension The focuser's extension tube has a locking lever that holds the extension tube firmly in position even when using heavy cameras such as large format cameras or CCD cameras with a large sensor. The locking lever clamps the rack gear to the extension barrel so that the viewing angle or focus on your camera does not shift. Compatible with motor driven focusers An optional two-speed motor focuser (not included) is available for the VSD90ss to provide sensitive focusing. An EAF (Electronic Automatic Focuser) from ZWO or equivalent can also be retrofitted. Optional VSD Reducer for even faster results The tried and tested optional VSD reducer, which was also used on the predecessor, the VSD 100, is also compatible with the VSD90ss. The photographer gets even faster results in astrophotography with an aperture ratio of 1:3.9. CHARACTERISTICS 90 mm aperture, 495 mm focal length (F5.5) Needle-fine stars up to the image field edge in 44x33 mm format 5 lens elements in 5 groups Image illumination up to 60 mm Resolution power: 1.29 Limit size: 11.5 Light gathering capacity: 165x Illumination: 60 mm Dimensions: 115 mm diameter x 600 mm length (476 mm length for storage) Weight: 4.3 kg Connections/Thread: Size thread/84 mm (pitch 1 mm), 60 mm (pitch 1.0 mm), 42 mm for T-ring push fit / 60.2 mm, 50.8 mm and 31.7 mm Solar observation: separately available solar projection approach B Optional VSD100 reducer compatible (opening ratio F: 3.9) SCOPE OF DELIVERY VSD90ss high performance astrograph

Available

€6,399.00*
Vixen SD103SII Telescope OTA
The Vixen SD103SII Telescope OTA is a new 103 mm apochromatic refractor with high-performance Super-ED glass (= SD). The advantage of this SD refractor is its short length and low weight. The FPL53 glass reproduces an extremely clear and sharp image by an exceptionally high degree of elimination of residual chromatic aberrations. The SD glass is designed to bring all beams of violet, red, blue, yellow and green very precisely together on the same plane. The special lens material reduces chromatic aberration across all colours.The new Vixen SD103SII no longer uses spacer plates, which leads to a significantly better image quality, especially with bright stars. In photographic images, no spikes can be seen on the stars, which were otherwise produced by the spacer plates. In addition, you will be thrilled when you look at the moon or the brighter planets and observe the moon craters pin sharp as well as with extremely high contrast. Also look at the ring planet Saturn or the cloud bands on Jupiter. But of course, brighter deep sky objects such as the Orion Nebula or the Andromeda Galaxy can also be observed in impressive detail.In combination with the new optional SD Reducer HD Kit or SD Flattener HD, these refractors allow illumination with a 44 mm image circle for full format SLR cameras. The older ED81SII, ED103S, ED115S refractors were originally developed for visual observers and photographers using APS-C cameras. However, the new SD series is also optimised for use with full-frame cameras through the use of new inner baffle rings. The large 60 mm eyepiece extension also allows heavy cameras to be attached without tilting. Furthermore, the included folding mirror allows comfortable observation even in unfavourable observation situations and additionally offers a T2 thread for connecting a DSLR camera. This allows you to observe in straight line or at a 90° angle. The carrying handle attached to the tube clamps ensures a secure grip when transporting the telescope. FEATURESObjective lens: D=103 mm, multi-coated 2-lens SD apochromat without spacer plates No more spikes on the stars Focal length: 795 mm (f7.7) Resolution and limiting magnitude: 1.13 arcseconds; 11.8 Light gathering power: approx. 217x more than the human eye Dimensions and weight: 115 mm dia x 810 mm; 5.5 kg Viewfinder telescope: 7x50 illuminated Adapters and connections: 60 mm thread, 50.8 mm and 31.7 mm socket, thread for T-ring Connection: 50.8 mm and 31.7 mm socket with flip mirror / folding mirror Photography: primary focus and eyepiece projection SCOPE OF DELIVERY Refractor SD103SII Telescope (OTA) Tube clamp with dovetail Dew cap Flip mirror / folding mirror Carrying handle Dovetail rail 7x50 viewfinder

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€2,199.00*
Vixen SD Reducer HD Kit
High-performance flattener and reducer set connection rings for Vixen telescopes SD81S, SD103S and SD115S, as well as the ED predecessor series. High-performance flattener and reducer set The kit consists of a high-performance flattener, a reducer for reducing the focal length, and connection rings (distance ring SD81, EX Tube 66), which were developed for prime-focus astrophotography with the SD81S, SD103S and SD115S telescopes. The flattener and the 0.79x reducer deliver a significant increase in telescope performance and image quality. You obtain a flat and sharp image until the edges, including with a full-frame DSLR camera. Ultra-sharp image over the entire field of view of the DSLR full-frame sensor The SD flattener improves the image quality to the edge of the field of view without changing the original focal length of the telescope. The field of view of the DSLR camera with a full-frame sensor is fully illuminated (44 mm), ensuring that stars appear sharp until the edges of the image. When used in conjunction with the Reducer HD, the focal length is reduced by a factor of 0.79 (f/7.7→6.1) whilst maintaining the 44 mm illumination. High-contrast AS coating The anti-reflex AS coating, which is also used on our high-end VSD 100 f/3.8 astrograph, delivers a high light transmission of 99.9% per lens surface. Loss of light, ghosting and scattered light images are virtually eliminated thanks to the completely matte interior coating. FEATURES Reduces the focal length by a factor of 0.79 Designed for full-frame cameras High-contrast AS coating Ultra-sharp image over the entire field of view Designed for full-frame DSLR cameras Illumination: 44 mm Correct distance to chip: 63.5 mm Designed for the SD81S, SD103S and SD115S Also suitable for the ED81S, ED103S and ED 115S DELIVERY CONTENT SD Flattener HD Reducer HD Adapter ring for SD81 66 mm EX extension tube Dust caps

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€499.00*
Vixen VA225C Autoguider Camera
The Vixen VA225C autoguider camera is designed to tackle common challenges in astrophotography, such as atmospheric interference and minor tracking errors that can cause star trails during long exposures. When paired with an optional guide scope, this highly sensitive colour CMOS camera continuously monitors star positions and automatically adjusts your equatorial mount in real time to correct for any deviations. This allows you to capture sharp, long-exposure images — especially useful when using telescopes with longer focal lengths. Beginner-friendly operation The VA225C makes it easy for newcomers to get started with autoguiding. Simply connect the camera to your telescope mount using the included ST4 cable for fully automated tracking control. The dedicated “Vixen Autoguider” PC software offers three preset guiding modes — City, Suburban, and Dark Sky — tailored to different viewing conditions. You can also fine-tune the settings to suit specific locations and atmospheric conditions if needed. Accurate polar alignment — without a polar finder With its built-in plate solving functionality, the VA225C allows for precise polar alignment without the need for a separate polar finder. You can check the alignment accuracy in real time via the software interface and make direct adjustments on the spot. This feature simplifies your setup process and ensures optimal conditions for successful astrophotography sessions. Exceptional sensitivity and flexible connectivity Thanks to its excellent light sensitivity, the VA225C can reliably detect suitable guide stars even with very short exposures. The camera comes with a 1.25" nosepiece for connection to guide scopes or off-axis guiders, a 1.25" filter thread (M28.5x0.6), and a C-mount thread (1" x 1/32"). We recommend the Vixen 7x50mm Finder Scope II (sold separately, item no.: X086161) as a guide scope. Its parfocal design ensures the focus remains consistent when switching between an eyepiece and the camera — so your guide star stays locked in view. FEATURES Highly sensitive SONY IMX225 colour CMOS sensor (1/3 inch) Plate solving for precise polar alignment without polar finder User-friendly Vixen Autoguider software Resolution: approx. 1.2 megapixels Pixel size: 3.75 µm x 3.75 µm ST4 autoguider port (6-pin modular socket) 1.25" nosepiece (31.7 mm) for guide scopes and off-axis guiders 1.25" filter thread (M28.5x0.6) C-mount thread (1" x 1/32") USB Type B port Powered via USB 2.0 (from PC) Compatible with Windows 7, 8, 10, 11 SCOPE OF DELIVERY Autoguider camera ST4 connection cable USB cable Instruction manual

Currently unavailable

€219.00*
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EXPLORE SCIENTIFIC 100° Ar Eyepiece 20mm (2")
These eyepieces with their huge apparent field of view not only gave the observer a panoramic visual experience, but they relax the eye so the observer could pay attention to subtle details for extended periods. These ultra-wide angle eyepieces played a critical role in the military for aiming at targets, and their long eye-relief counterparts helped reduce eye injury from recoil. Each 100° Series Nitrogen-Purged Waterproof eyepiece is internally sealed and purged with inert, dry nitrogen gas to prevent internal fogging, to halt the intrusion of fine particulates and fungus, and to maximize the life of the internal coatings. To make sure, every 100° eyepiece is tested by submerging them down to 1 meter of water for 30 minutes. All 100° Series eyepieces are fully multi-coated and edge-blackened to produce maximum contrast.

Available

€519.00* €649.00* (20.03% saved)