EXPLORE SCIENTIFIC 2" S-II Nebula Filter 12nm

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 bejond the solar systems enourmously. Depending on the type of the celestial object it is possible to increase the contrast dramatically by blocking the annoying artifical light. The Explore Scientific H-beta filter uses a characteristic property of the so called emmission nebulae. Those objekcts glow in special colors, the so called emmission lines. Those emmission lines are linked to chemical elements - in this case hydrogen. The Explore Scientific H-beta nebula filter blocks all other colors (and thereby nearly all of the artificial light) and only the emmission line of the hydrogen can pass the filter. The result is astonoishing: suddenly nebulae are visible at locations that were completely empty without filters. In suburbian skies for example the horsehead nebula is almost not visible with a 300mm 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.

Universal Dark-Sky Filter with 77mm thread for photo lens. Contrast enhancing filter for Aurora- and Deep-Sky imaging. Especially during Aurora imaging the most important wavelength of 550nm (green) and 630nm (red) this filter let pass by 90%. In comparrision to CLS filters, the Explore Scientific Dark-Sky Filter is blocking also the yellow Sodium (Na) wave at 590nm which elliminates Sodium-lamp street illumination from your picture. This is very useful because the yellow light is always a partially mix of green and red light. Removing the yellow wave-length with any image processing software will always damping also the green and red coloring. For Aurory imaging this is of course not wanted. At these days of increasing light pollution, the Explore Scientific Dark-Sky Filter is absolutely recommended in order to take pictures also from urban conditions. Finally the slim housing design enables its use also with wide-field photo lens and doesn´t cause any vignetting. Pictures at night taken by Bernd Pröschold - www.sternstunden.netTest report:  http://www.sternstunden.net/filter-testing.html  FEATURES Deep Sky Filter Contrast enhancer for Aurora- and Deep-Sky imaging Wide field imaging of the milky-way, time lapse and landscape Lightpollution damping filter Ellimintates the yellow light which can´t be done by any imaging processing software Black anodized filter housing 77mm filter thgread for foto lens flat design of only 4mm height (slim) - no vignetting Ideal also for wide field foto lens Made from optical glass with Neodymoxid SCOPE OF DELIVERY Deep Sky Filter 77mm Dust protection case

One of the most important obstacles for the exploration of the night sky is the brightening of the night sky by artificial lighting, such as street lights. The night sky is not really dark in the vicinity of towns or cities, which reduces the visibility of objects beyond the solar system enormously. Depending on the type of celestial object, it is possible to increase the contrast dramatically by blocking the interfering artificial light. The EXPLORE SCIENTIFIC O-III filteruses 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 filterblocks all other colours (and thereby nearly all the artificial light) and only the two emission lines of the oxygen can pass the filter. The result is astonishing: suddenly, nebulae are visible in locations that were completely empty without using filters. In suburban skies, for example, the veil nebula NGC 6992 is almost invisible with a 200 mm telescope. By using this filter, you can see the nebula and its structures without any difficulties. A must for every visual observer and for astrophotography. The EXPLORE SCIENTIFIC nebula filterscome with an individual test certificate - your guarantee for receiving a premium filter. This filter's narrow passband of only 6.5 nm bandwidth highlights the faint emission nebulae or makes them visible even under difficult urban conditions. FEATURES enables the observation of so-called emmission nebulae blocks almost the entire artificial light only the two emmission lines of the oxygen passes the filter band pass width: 6.5 nm narrow band version for difficult urban conditions allows more contrast for faint deep sky objects ideal for use near cities, in heavy brightened skies individual test certificate included to guarantee you receive a premium filter SCOPE OF DELIVERY 1x 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 lighting, 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 system enormously. Depending on the type of celestial object, it is possible to increase the contrast dramatically by blocking the interfering artificial light. The EXPLORE SCIENTIFIC S-II filter uses the property 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 ionized sulfur. The EXPLORE SCIENTIFIC S-II nebula filter blocks all other colors (and thus almost all artificial light) and lets only the emission lines of ionized sulfur at 672 nm through. The effect is amazing: suddenly, nebulae become visible in places that appear completely empty without the filter. In slightly brightened skies, many planetary nebulae, emission nebulae and supernova remnants can be seen without any difficulties when using this filter. A must for every visual observer and for astrophotography. EXPLORE SCIENTIFIC nebula filters come with an individual test report - so you can be sure to get high quality filters. FEATURES Simplifies the observation of planetary nebulae, emission nebulae and supernova remnants Blocks almost all artificial light Only lets the emission lines of ionized sulfur at 672 nm pass Transmission bandwidth: 6.5 nm Allows for more contrast in faint deep sky objects ideal for use near cities, in heavy brightened skies individual test certificate included to guarantee you receive a premium filter SCOPE OF DELIVERY 1x 2'' S-II nebula filter

Besides air turbulence, the brightening of the night sky is the biggest obstacle to observing faint objects beyond the solar system. Street lamps and other artificial lighting mean that the sky in human settlements is no longer really black. This affects the contrast and thus the perception of deep-sky objects. Depending on the type of celestial object, however, part of disturbing artificial light can be filtered out, making it easier to observe fainter targets.The EXPLORE SCIENTIFIC CITY LIGHT SUPRESSION - or CLS - filter uses the fact that the artificial lighting is not evenly distributed over the entire spectrum. These colours - in the case of the EXPLORE SCIENTIFIC CLS nebula filter, above all the typical colours of mercury and high-pressure lamps, used in street lighting - are suppressed, but the emissions of deep-sky objects are allowed through. With a slightly brightened sky, some relatively bright deep-sky objects are practically invisible with a telescope, for example the large galaxy M101. Using this filter makes observation much easier. A must have for any visual amateur astronomer.  The CLS can also be used as a useful photographic filter - helping to improve the quality of your telescopic deep sky photos.The EXPLORE SCIENTIFIC nebula filters are delivered with an individual test report - so you can be sure of receiving high-quality filters.SPECIFICATIONS:eliminates disturbing light - e.g. from street lightingenables observation of faint deep sky objectsWHAT'S INCLUDED:1x nebula filter

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 photos in locations which appear completely empty without the filter.The EXPLORE SCIENTIFIC H-Alpha Nebula filter has been developed exclusively for astrophotography. 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 the 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 2'' H-Alpha Nebula Filter

Adapter 2" with brass locking ring for 1,25" eyepieces. The integrated T2 thread adapts DSLR or astro-cameras (*appropriate T2 ring for your camera model needed). On the telescope side there is a 2" filter thread M48x0.75, which allows the easy use of colour and nebula filters.SCOPE OF DELIVERYCamera Adapter