EXPLORE SCIENTIFIC 1.25" O-III Nebula Filter

Explore Scientific 82° Series™ extreme wide field eyepieces are optimized to produce high contrast, high resolution, and superior flat field characteristics. The visual effect of these eyepieces with their long eye-relief and their 82° apparent field is truly a full-immersion experience. Your eye is relaxed, allowing you to easily use the "averted vision" technique to study faint details across a huge field-of-view. The 82° Series eyepieces come with a twist-up rubber eye-guard that raise to the desired height for the comfort of the observer, and as experienced astronomers know, eye comfort is critical when trying to observe at the visual limits of the telescope. To keep internal reflections to a minimum, all internal surfaces of the eyepiece barrel are flat black, as well as the edges of the lenses themselves to minimize the scattering of light within the lenses themselves. All 82° Series eyepieces are fully multi-coated and edge-blackened to produce maximum contrast.

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

Filter Set 3 is recommended for Moon & Planets from 150mm (6") Aperture Set 3 includes the following filters: Explore Scientific Filter 1.25" Light Blue No.82A - 0310265 The color of light blue really supports watching the high clouds on Mars. The contrast increases. The dark red structures will be shown even darker, so this is the perfect filter for watching the big red Flecks on the gas planet Jupiter. The rings of Saturn will be accentuated, the structures of the Venus Atmosphere will be even finer. Explore Scientific Filter 1.25" Violet No.47 - 0310272 The purple filter is perfect for watching Venus. Seeing through it, the dark clouds of the Venus atmosphere become even better visible. He also clears up the structures of the rings around Saturn. Using big openings and having a clear sight this filter is also good for watching Merkur. Explore Scientific Filter 1.25" Light Red No.23A - 0310271 The blue/blue green light is totally blocked. The contrast between the card and the lighter zones will enormously increase. This is truly helpful when you watch Jupiter or Saturn. Or for mars, watching the poles. Explore Scientific Filter 1.25" Yellow-Green No.11 - 0310269 Watching the Moon surface through the filter, the contrasts will enormously increase. Same with planet Mars. On the huge planet Jupiter, when using the filter, you can even see the contrasts between the cloud-bands and a lot more details. Starting with a telescope diameter of 8“ and a clear sight, you even get to see various details of Saturn. What ist a color Filter for and do we really need it? Color Filters darken the light slightly, that reaches the eye or the sensor of the camera. This eliminates for instance stronger transitions. The result is that your picture turns out with more contrast which automatically shows more details. FEATURES Made from high-quality optical glass Filter glass is absolutely parallel All optical surfaces have anti reflex coatings Filter housing from black anodized aluminum Filter threads on both ends (female/male) Multiple filters usage is possible SCOPE OF DELIVERY 4pcs color filter 4pcs protection-case

Apart from air turbulence, the brightening of the night sky is the greatest barrier to observing faint objects beyond the solar system. Due to streetlamps and other artificial lighting, the sky in urban areas is no longer properly black. As a result, the contrast and thus the perception of deep-sky objects also suffer. However, depending on the type of celestial object, it is possible to filter out some of the interfering light making it easier to photograph the objects.The EXPLORE SCIENTIFIC H-Alpha filter uses the characteristic of the so-called emission nebulae. These objects glow in certain colors, the so-called emission lines. The emission lines are associated with certain chemical elements - in this case the red glowing hydrogen. This filter blocks all other colors (and therefore almost all artificial light) and lets only the emission lines of hydrogen through. Especially the interfering light of mercury and sodium vapor lamps is effectively blocked. The effect is amazing: suddenly, nebulae become visible on the photos in locations which appear completely empty without the filter.The EXPLORE SCIENTIFIC H-Alpha Nebula Filter has been developed for astrophotography exclusively. Especially in slightly light-polluted skies many emission nebulae only become visible and are shown in full expanse on astrophotos when using this filter. The H-Alpha nebula filters make astrophotography near the city possible and the use leads to amazingly good image results despite the existing light pollution. A must for every urban astrophotographer.The EXPLORE SCIENTIFIC nebula filters are delivered with an individual test report - so you can be sure to get high quality filters.FEATURESH-Alpha filters are used for astrophotography exclusivelyAllows photography of emission nebulae that glow in the light of red hydrogenMany of these emission nebulae are only visible in their full expansion in photos taken with this filterBlocks almost all artificial light, especially from mercury and sodium vapor lampsOnly allows the emission line of red hydrogen to pass throughTransmission bandwidth: 12 nmAllows more contrast and detail for all urban astrophotographersIdeal for use near cities, in slightly brightened skiesIndividual test certificate included to guarantee you receive a premium filterSCOPE OF DELIVERY1x 1.25'' H-Alpha Nebula Filter