Explore Scientific ED 127 CF – FCD01 compared to FCD-100
A product test: two models in direct comparison. Von J.S. Schlimmer
1. Introduction
Figure 1: Explore Scientific ED 127 CF models under test
Since April 2016 I own the apochromatic one Refractor ED 127 CF, Model FCD01 by Explore Scientific and I use it for moon and planetary observation as well as for the photography of extended nebulas, open star clusters and galaxy clusters. In addition to the very good look, the possibility for photographic use with the help of a focal reducer, also the low weight of the telescope has influenced my purchase decision. Therefore, I could continue to use my old mount and invest the existing budget in optical accessories. The telescope is still transportable and thus suitable for mobile use outside the light-polluted cities.
Explore Scientific is listed as a Bresser brand. The technical support I approached initially for some questions was very friendly, accommodating and very helpful.
2. Description
The ED 127 CF has a three-lens lens. Between the lenses there is an air gap. The tube is made of carbon fiber and processed to high quality. The ED 127 CF has a three-lens objective. There is an air gap between the lenses. The tube is made of carbon fiber and processed to high quality. Thanks to its low weight of only 7 kg, it can still be carried by a GP-DX or comparable mount.
Since November 2016, the improved FCD-100 model is on the market, which is advertised with high color purity and a perfect optical design. What’s the difference between these two models? To test this, Bresser has kindly provided me with an ED 127 FCD-100.
At first glance, both models resemble each other like twins, as my older model also has the 2.5-inch Hexafoc extract. In addition to the stable construction, it can also be rotated as a whole. In astrophotography this offers the advantage of preserving the focal position, even if the camera needs to be realigned for another object. The 1:10 reduction allows an exact focus. A scale applied on the pullout facilitates the presetting (Figure 2). In the case of visual observation the zenith mirror can of course be adjusted independently of the focuser.
Figure 2: Camera, 0.7x Focal Reducer and Hexafoc Extract
Both models have an aperture of 127 mm and a focal length of 952 mm. In lens labeling, the new model differs only in the additionally printed model designation. Only by closer inspection you can see that the tube of the new model FCD-100 is 15mm shorter. This is a great advantage, because my intrafocal area is very short on my own model. Therefore, in my model, orthoscopic eyepieces (e.g. measuring eyepieces) cannot be used if the extension is provided with an extension sleeve. With my wide-angle eyepieces the extension sleeve always comes to commitment.
3. Objective lenses
For observation I prefer to use wide-angle eyepieces. For almost 2 years my Nagler range has also been supplemented by eyepieces in the 82° series by Explore Scientific. For the telescope comparison the Explore Scientific 2-inch eyepiece with 24 mm focal length, as well as two Explore Scientific 1 ¼ inch eyepieces, with 8.8 and 4.7 mm focal length were used.
4. Explore Scientific 0.7 focal reducer and corrector
of 64 mm (2.5 inches). To connect to Canon cameras, a special T2 adapter must be used. The adapter ring is only 1 mm thick and therefore made of steel. He has a free opening of 36.7 mm.
5. Visual tests
Figure 3: Explore Scientific 82 ° Series Eyepieces
In particular, moon and planets are suitable as test objects for the visual comparison, while in the deep sky range the Orion comes into question with its richness of detail. Open star clusters, on the other hand, offer a very good opportunity to assess the edge imaging at low magnifications.
For the tests, the objects should be as high as possible in the sky, where the influence of astronomical seeing is significantly lower. Because the planets only reached a height of 23° at the meridian passage at the time of the tests, they were out of the question for the tests. For better temperature adaptation, the telescopes were brought to the open air 1-2 hours before the tests.
At dusk on the 23rd of February
In 2018, Aldebaran was covered by the moon. The picture above shows the moon a few seconds before covering on the bright Sky. The small image inside shows the entire image field during the covering. The picture below shows the moon for one hour at the end of the Aldebaran covering. ES 127 FCD-100 and Focal Reducer, Canon 1100D
a) The moon
With the 2-inch 24 mm eyepieces, the moon fits comfortably in the field of vision. While the FCD01 showed a light, yellow color fringe around the bright edge of the crescent, the image of the successor model FCD-100 was without any color aberrations. The higher the magnification the more details revealed on the lunar surface. The sight became really fascinating at 200x magnification with the 4.7 mm eyepiece.
In the Apennine Mountains were already single, larger rock formations to recognize. In the south, on the edge of the Mare Nubium, the Long Wall was just visible, an approximately 100 km long embankment. The crater Thebit could be easily observed on one side of the long wall and Birt and the side crater Birt A on the other side. On closer inspection you could see further small craters such as e.g. Thebit D at the end of the long wall. Also Rima Birt, a groove that runs almost parallel to the Long Wall, but only as half long, was easy to see.
Below are some pictures of the Aldebaran covering from 23rd February 2018. The
beginning was still in the clear sky, so that Aldebaran was difficult to locate.
At the exit one hour later the sky was already dark.
b) Open star cluster: Pleiades and NGC 1647
For the observation of the Pleiades also the 2-inch 24 mm eyepieces was used. With this eyepiece, the Pleiades are a breathtaking sight, because they fit completely into the field of view. In both telescopes, the stars were as fine as needle points and point-shaped to the edge. Visually, no color errors were noticeable. It was such a perfect sight.
NGC 1647 is a very loose open star cluster nearby 97 Tau. Because it is very extensive, it is best seen at low magnification. Approximately 20 stars with a brightness of 8 mag can be captured well with the 2-inch 24-mm eyepiece. Again, the sight is fantastic, as the entire field of view is sharply displayed.
c) Stars and binary stars
AFigure 5: Intrafocal and extrafocal diffraction disks
What about the comparison at high magnifications? Inadequate color correction of refractors is shown by blue color fringes around bright stars. To test this, the choice fell on Bellatrix, the "warrior" in Orion. This star is 1.6 mag bright, bluish giant star of the spectral class B2. At moderate magnification with the 8.8 mm eyepiece (108x), neither the CD01 nor the successor FCD-100 showed any fringing. At high magnification with the 4.7 mm eyepiece (203x), diffraction rings around Bellatrix were clearly visible, but no fringing. However, at this magnification already the atmospheric dispersion was noticeable, as Bellatrix only reaches a height of 46 ° in the meridional passage. The atmospheric dispersion is shown by blue color in the upper area and red color in the lower area of the star. However, it is an atmospheric effect and not due to the telescope optics.
In the constellation Orion there are also numerous binary stars, which can be used to test the resolution. For example, 32 Ori (STF 728) could not be resolved at a distance of about 1.2 arcseconds. For 52 Ori (STF 795), which has a spacing of only 1.0 arcseconds, both components could be detected but not completely separated. The reason for this is in different contrast: the components of 32 Ori have a brightness difference of 1.3 magnitudes, while the components of 52 Ori are equally bright. The observation of Alnitak (STF 774), the eastern belt star of Orion was also interesting. With a distance of at least 4.7 arc seconds, this double star should be easy to separate, despite its brightness difference of 1.8 magnitudes. At 203x magnification Alnitak was also clearly to separate, however the B-component could only be seen at second glance in the diffraction rings. With the 8.8 mm eyepiece Alnitak was inseparable.
Of course, with this type of observation, astronomical seeing plays a crucial
role. Unfortunately, lunar observation was only possible with good astronomical
seeing. At all other tests the astronomical seeing was not very good. In
conclusion, the difference between the two models FCD01 and FCD-100 is hardly
noticeable in visual observations.
6. Photographic tests
a) Diffraction slices in the primary focus
To get a better overview of the color difference between the two models, the defocused diffraction discs were first used recorded in the primary focus at 952 mm focal length (Figure 5). For this a QHY 5L II-C color CMOS camera was used. The images were taken at a distance of -2.2, -1.1, 0, +1.1 and + 2.2 mm from the focus. The light source was Bellatrix.
Overall, my model FCD01 showed slightly more color differences between the intra- and extra-focal diffraction slices. In the intrafocal area it appears slightly greenish, while in the extrafocal area it shines reddish. The successor model FCD-100 shows no color differences between the intra- and extra-focal diffraction disks.
Figure 6: Orion Nebula 16 x 30 seconds, 800 ASA, ED127 CF FCD-100, 0.7 x Focal Reducer
a) Astrophotography with the Explore Scientific 0.7x focal reducer
Figure 7: Bellatrix and Betelgeuse, 5x30 seconds, 800 ASA
Figure 8: Complete picture of Betelgeuse, the inlays show the Star illustrations in the corners on the lower left and upper right
The photos in this review were taken with a modified Canon EOS 1100D. It can also be used for the absorption of hydrogen regions due to the lack of red filter. For the recordings, the camera was connected directly to a laptop via a USB cable and operated exclusively via the Canon "long-distance shot" menu. The focus was set on the live image in 10x zoom mode. Exposure time and sensitivity were also controlled via the laptop. The pictures could be viewed directly after the picture was taken on the screen. The pictures were taken with an exposure time of 30 seconds at 800 ASA. To reduce noise, flat and dark images were also created.
With my FCD01 model, the sharpness can be easily adjusted by the color of the diffraction disk. As soon as the color becomes minimal, or changes from a slight green cast to reddish, the perfect focus is found. This method always worked well and led to quick results. In which Successor model FCD-100, this method could not be applied due to the color purity. Therefore it took some practice to find the right focus. A self-made focusing aid has proven to be helpful. The focusing aid consisted of a ring that was placed on the dew cap. Attached to the ring was a thin ridge that ran through the center, creating a one-dimensional diffraction pattern in the image. Based on the diffraction image was the adjustment of sharpness.
The focusing aid was removed again for photography and bright stars in Orion were once again chosen as test objects. Figure 7 shows Bellatrix (spectral type B2) and Betelgeuse (spectral type M2) taken with the FCD01 and the FCD-100. Exposing time was 5 × 30 seconds and corresponding flat pictures were taken. The different colors are shown very nice in both models. Due to the red sensitivity of the camera, a correspondingly large halo appears around Betelgeuse.
Für For deep sky shots of extended objects not only the color but also the marginal image is of interest. Figure 8 therefore shows the complete picture of Betelgeuse taken with the FCD-100. The inlays show the star pictures in two opposite corners. The 0.7x Focal Reducer levels the image over the entire APS-C format of the camera. Very red stars in the border area are no longer 100% displayed due to dispersion phenomena. The strength of this effect depends on the spectral type of the star and of course on the red sensitivity of the camera and can be observed only at full image resolution (here 4273 pixels x 2848 pixels).
On the basis of the flat images, the vignetting of the two telescopes could also be determined very easily. The vignetting is shown by the edge darkening of the image field. In both models, the brightness drops to around 77% of the center brightness in the outermost corners. This corresponds to about half an aperture.
Figure 6 shows another shot of the Orion Nebula taken with the FCD-100. At the time of shooting, the sky was already lit by the half moon. The colors of the stars are rendered beautifully. There was no color correction during the image process, only the tonal values have been changed. In the predecessor model FCD01, the stars appear on deep sky shots usually with a slight green tint, which is easy to correct in subsequent image editing.
7. Conclusion
In all tests, the FCD-100 has shown no color errors, while the previous model FCD01 still has low color errors. With the improved look of the FCD-100, Explore Scientific / Bresser has reached the limits of color purity in imaging. Bei der Fotografie ist es beim FCD-100 schwieriger den exakten Fokus zu finden wie beim Vorgängermodell FCD01. Eine Fokussierhilfe und etwas Übung verhelfen aber auch hier zum gewünschten Ergebnis.
In photography, the FCD-100 is harder to find the exact focus like the previous model FCD01. A focus aid and a little bit of practice help to achieve the desired result.
The border image on both models is in conjunction with the Explore Scientific 0.7 x Focal Reducer APS-C format punctiform.
The image field illumination is very uniform and shows only slight vignetting.
The 2.5-inch Hexafoc extract is built mechanically very stable and can be rotated as a whole. This allows a camera to be arbitrarily aligned with the focus position almost preserved.
Due to the 15 mm shorter tube on the FCD-100 compared to the FCD01, the intrafocal area of the hexafoc is significantly larger. This also means that orthoscopic Eyepieces (for example, measuring eyepieces) can be used without removing the extension sleeve.
Overall, the Explore Scientific 127 FCD-100 is a fantastic 5-inch telescope that
impresses visually and photographically. In addition, it is transportable with a
weight of just under 7 kg and is also carried by a GP-DX or comparable mount.
Product information "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
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
This excellent telescope is the currently largest representative of a new line of apochromatic refractors by EXPLORE SCIENTIFIC. The completely new designed optics contains the special glas FPL-53, and delivers stunning sharpness and contrast without any trace of color abberation. For a apochromatic refractor of this size the focal ratio is relatively fast - the f/7 optics is thus also very suitable for astrophotography. For this reason we added one of the world’s top focusers - the high precision and the famed rigidity of the 3" Feathertouch focuser make focusing an easy task - and unwanted movements of the sensor during exposure do not happen. The result of this combination of outstanding optics, top level mechanics and the relatively low weight is a extremely versatile telescope that wil not only give images of the moon and planets that are perfect. It will also exceed the expectations of even the most demanding amateur astronomers in the field of astrophotography.These very popular EXPLORE SCIENTIFIC Triplet ED APO Refractors we do offer in 3 different product lines:Essential Line: HOYA FCD-1 Glass lens, AL-Tube, 2.0" Rack&Pinion Focusser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112084(AL), 0112106(AL), 0112132(AL)), 0112155(CF + 3"FT)) Professional Line: HOYA FCD-100 Glas lens, AL/CF-Tube, 2.5" HEXAFOC Focusser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112086(AL), 0112108(AL), 0112109(CF), 0112134(AL), 0112135(CF))High-End Line: OHARA FPL-53 Glass lens, Carbon(CF) Tube, 3.0" Feather-Touch Focusser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112165(CF))FEATURESexcellent color correctionRetractable dewshieldLightweight carbon fiber constructionSCOPE OF DELIVERY165mm tube CF (165/1155mm (6.5" f/7.0) FTF3235B-A Feather Touch® True 3.0" Dia Dual Speed Focuser2” Diagonal mirror with 99% coating06-20160 90° illuminated finderscope with true oriented viewTube rings with handle3“ Losmandy-type dovetailDeLuxe Flight case with wheels
Highly corrected 102mm air-spaced triplet apochromat (with three lenses) and aluminium tube and a 2.5" high-precision HEXAFOC focuser. Apochromats are the ultimate choice in small to medium sized telescopes: the combination of compactness, transportability, very high image contrast and sharpness together with the possibility to make excellent astrophotos cannot be bested. The advances in glass manufacturing during the last few years have made true apochromats available to more astronomy enthusiasts than ever before. The new Explore Scientific FCD-100 Alu Hex represents another major improvement in this field - the overall correction (color and spherical) is setting new standards in this price class. The optical design shows a polystrehl value of 0,97 indicating a level of correction that is absolutely top of the line.This excellent apochromat is a very versatile telescope: the fast f-ratio makes short exposure times possible. The high contrast and sharpness of the image provide breathtaking views of large objects like the North america nebula or the Andromeda galaxy as well as tack sharp planetary images. The telescope is lightweight and compact - the dew shield slides down the tube to minimize size for transportation. Revolutionary glass and precision manufacturing created a telescope that offers observing joy on the highest level. This does not only qualify this telescope as the ideal travel scope, it is also the perfect choice for fast observations and for astrophotography. The excellent 2,5" HEXAFOC focuser with 10:1 reduction is perfect for this - the large inner diameter of 65mm prevents vignetting by the focuser when the telescope is used for astrophotography with large sensors. These very popular EXPLORE SCIENTIFIC Triplet ED APO Refractors we do offer in 3 different product lines:Essential Line: HOYA FCD-1 Glass lens, AL-Tube, 2.0" Rack&Pinion Focusser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112084(AL), 0112106(AL), 0112132(AL)), 0112155(CF + 3"FT)) Professional Line: HOYA FCD-100 Glas lens, AL/CF-Tube, 2.5" HEXAFOC Focusser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112086(AL), 0112108(AL), 0112109(CF), 0112134(AL), 0112135(CF))High-End Line: OHARA FPL-53 Glass lens, Carbon(CF) Tube, 3.0" Feather-Touch Focusser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112165(CF))SPECIFICATIONSAperture: 102mmFocal Length: 714mmFocal ratio: f/7.0Weigth: 4,0kgBackfocus: 150mm above 2" adaptorDesign: Apochromat with three lenses, two air spaces and FCD-100 glassSCOPE OF DELIVERYOptical tube with retractable dew-shield2.5" HEX focuser with 1:10 gear reduction 2" Star Diagonal 99% reflectivityTube rings with dovetail plate and handleDust caps for front-lens and focuserUniversal finder slot
Highly corrected 127mm air-spaced triplet apochromat (with three lenses) and carbon fibre tube and a 2.5" high-precision HEXAFOC focuser. NEW: Now with hybrid viewfinder shoe to accept different viewfinder holders. Apochromats are the ultimate choice in small to medium sized telescopes: the combination of compactness, transportability, very high image contrast and sharpness together with excellent astrophotographic performance cannot be bested. The advances in glass manufacturing during the last few years have made true apochromats available to more astronomy enthusiasts than ever before. The new Explore Scientific FCD-100 CF Hex represents another major improvement in this field - the overall correction (colour and spherical) is setting new standards in this price class. The optical design shows a polystrehl value of 0.97 indicating a level of correction that is absolutely top of the line.This excellent apochromat is a very versatile telescope: its reasonably fast f-ratio makes for short exposure times when imaging deep sky objects, but it is still of a significant focal length, making higher power planetary and lunar observation comfortable without having to use really high magnification eyepieces. The high contrast and sharpness of the image provide breathtaking views of large objects like the North America nebula or the Andromeda galaxy, as well as tack sharp planetary images. The telescope is lightweight and compact - the dew shield slides down the tube to minimize size for transportation. Revolutionary glass and precision manufacturing come together to deliver a telescope that offers observing and imaging at the highest level. The Carbon Fibre construction allows this telescope to be used on lower capacity mounts, increasing convenience and portability. Although there are smaller instruments available, the combination of aperture and optical excellence at such a low weight and compact tube makes this an excellent travel scope. The well-designed 2.5" HEXAFOC focuser with 10:1 reduction is perfect for both visual and astrophotographic use - the large inner diameter of 65mm prevents vignetting by the focuser when the telescope is used for astrophotography with large sensors (full frame and above).We offer the very popular EXPLORE SCIENTIFIC Triplet ED APO Refractors in 3 different product lines:Essential Line: HOYA FCD-1 Glass lens, AL-Tube, 2.0" Rack & Pinion Focuser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112084(AL), 0112106(AL), 0112132(AL)), 0112155(CF + 3"FT)). Professional Line: HOYA FCD-100 Glass lens, AL/CF-Tube, 2.5" HEXAFOC Focuser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112086(AL), 0112108(AL), 0112109(CF), 0112134(AL), 0112135(CF))High-End Line: OHARA FPL-53 Glass lens, Carbon(CF) Tube, 3.0" Feather-Touch Focuser with 1:10, 2.0" Star Diagonal 99% Reflectivity (see Part No. 0112165(CF))SPECIFICATIONSAperture: 127mmFocal Length: 952mmFocal ratio: f/7.5Design: Apochromat with three lenses, two air spaces and FCD-100 glassWeight: 5.2kg, lightweight due to carbon fibre tubeBackfocus: 150mm above 2" adaptorHybrid viewfinder shoe to accept different viewfinder holdersWHAT'S INCLUDED Optical tube with retractable dew-shield2.5" HEX focuser with 1:10 gear reduction 2" Star Diagonal 99% reflectivityTube rings with dovetail plate and handle Extension tubes for focuser (2pcs)Dust caps for front-lens and focuserHybrid viewfinder shoe
Highly corrected 127 mm air-spaced triplet apochromat (with three lenses) and aluminium tube and a 2.5'' high-precision HEXAFOC focuser. NEW: Now with hybrid viewfinder shoe to accept different viewfinder holders.
Apochromats are the ultimate choice in small to medium-sized telescopes: the combination of compactness, transportability, very high image contrast and sharpness together with the possibility to make excellent astrophotos cannot be bested. The advances in glass manufacturing during the last few years have made true apochromats available to more astronomy enthusiasts than ever before. The new Explore Scientific FCD-100 Alu Hex represents another major improvement in this field - the overall correction (colour and spherical) is setting new standards in this price class. The optical design shows a polystrehl value of 0.97 indicating a level of correction that is absolutely top of the line.
This excellent apochromat is a very versatile telescope: the fast f-ratio makes short exposure times possible. The high contrast and sharpness of the image provide breathtaking views of large objects like the North America nebula or the Andromeda Galaxy, as well as tack sharp planetary images. The telescope is lightweight and compact - the dew shield slides down the tube to minimize size for transportation. Revolutionary glass and precision manufacturing created a telescope that offers observing joy on the highest level. This does not only qualify this telescope as the ideal travel scope, it is also the perfect choice for fast observations and for astrophotography. The excellent 2,5'' HEXAFOC focuser with 10:1 reduction is perfect for this - the large inner diameter of 65 mm prevents vignetting by the focuser when the telescope is used for astrophotography with large sensors.
These very popular EXPLORE SCIENTIFIC Triplet ED APO Refractors we do offer in 3 different product lines:
Essential Line:
HOYA FCD-1 Glass lens, AL-Tube, 2.0'' Rack and Pinion Focusser with 1:10, 2.0'' Star Diagonal 99% Reflectivity (see Part No. 0112084(AL), 0112106(AL), 0112132(AL)), 0112155(CF + 3''FT)
Professional Line:
HOYA FCD-100 Glass lens, AL/CF-Tube, 2.5'' HEXAFOC Focusser with 1:10, 2.0'' Star Diagonal 99% Reflectivity (see Part No. 0112086(AL), 0112108(AL), 0112109(CF), 0112134(AL), 0112135(CF))
High-End Line:
OHARA FPL-53 Glass lens, Carbon(CF) Tube, 3.0'' Feather-Touch Focusser with 1:10, 2.0'' Star Diagonal 99% Reflectivity (see Part No. 0112165(CF))
SPECIFICATIONS
Aperture: 127 mm
Focal Length: 952 mm
Focal ratio: f/7.5
Design: Apochromat with three lenses, two air spaces and FCD-100 glass
Weight: 7.7 kg
Back focus: 150 mm above 2'' adaptor
Hybrid viewfinder shoe to accept different viewfinder holders
SCOPE OF DELIVERY
Optical tube with retractable dew-shield
2.5'' HEX focuser with 1:10 gear reduction
2'' Star Diagonal 99% reflectivity
Tube rings with dovetail plate and handle
Dust caps for front-lens and focuser
Hybrid viewfinder shoe
The Vixen corrector PH is a 3-element Wynne corrector for demanding applications. Designed for the Vixen R200SS Newtonian reflector, but also suitable for other optics with similar specifications.The optical design consists of 3 lenses in 3 groups. The corrector provides excellent correction of system-induced coma of parabolic mirrors and the resulting spherical aberration. The corrected field has a diameter of 44 mm, making it suitable for the 24x36 mm format (full-frame DSLR/CCD cameras). This guarantees razor-shape images across the entire field. The lens surfaces are coated with a cutting-edge 99.9% anti-reflective AS coating, which is also used for Vixen's flagship VSD100F3.8.Turn your Vixen R200SS reflector telescope into the perfect astrograph!FEATURESPremium coma corrector for the R 200SS Newton refelctor 3 lens systems in 3 groups, guarantees absolute colour purity and sharp stars to the edge of the field of viewImage illumination up to 44 mm for full-frame imagesReduces the focal length of the R 200SS from 800 mm to 760 mm 1:3.8Also suitable for visual observations with an eyepiece adapterWeight: 175 gDELIVERY CONTENTComa correctorDust caps on front and back
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
Camera specific bayonet adapter (camera ring) for Canon EOS DSLR with M48x0.75 mm internal thread for astrophotography. By using the large thread M48x0.75 mm, the vignetting of e.g. a DSLR full format sensor is effectively avoided. Compared to the small T2 thread M42x0.75, this adapter has a free inner diameter of 47.5 mm. This camera ring is made of matt black anodised aluminium and weighs only 40 grams. The light path (overall length) is 10.0 mm. FEATURES Camera-specific bayonet adapter Canon EOS Large female thread M48x0.75 mm Free inner diameter of 47,5mm No vignetting for full format sensors Light path (overall length) is 10.0 mm Made of matt black anodized aluminium Weight only 40 grams SCOPE OF DELIVERY Camera ring for Canon EOS (1 piece)
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
After three years of testing and refining we are extremely proud to present the new Explore Scientific High Resolution (HR) Coma Corrector. This corrector is a class of it´s own - it is fully functional for visual use and expands the focal length by only 6%! The Explore Scientific Coma Correktor is delivered as a complete set together with a rotating helical focuser with laser-etched scale, so you get a full package: corrector, adaptor to T2 (M42x0.75mm), adaptor to M48 (M48x0.75) and the helical focuser for visual fun.
This coma corrector really is "high resolution" - it deliveres a visual polystrehl performance of 0,98 at f/4 and 0,96 at f/3! So it can stay in the telescope - and you will not only enjoy a tack-sharp Jupiter, but aslo sharp and defined moons in the future!
What this means in terms of performance is shown in the three pictures with the graphs - the sharpness increase in those comparisons with and without corrector are stunning (examples are 400mm f/4, f/3,5 and f/3).
Please notice: These graphs are for FLAT FIELD! You will get this performance without refocussing!
Diameter of the field is 30mm - it doesn´t make sense to increase this with 2" and fast optical systems. Length of the 2" corrector barrel is approx. 85mm and it can be used with almost all 2" focusers on the market. To use the HR Coma Corrector visually, you need to have at least 32mm spare inward travel at your focuser, while the focus is on the same plane as the focusers end. Photographically there is no problem - the HR Coma Corrector shifts the focus outward by about 35mm, so that you will have no problem in achieving focus, when you are able to focus your camera without the HR Coma Corrector.
FEATURESEliminates coma, field-curvature and astigmatism in newtonians Diffraction limited performance on axis and in the field Flattens the field Works for very fast systems down to f/3
Four-lens construction Can be used with almost all 2" focusers on the market SCOPE OF DELIVERY High Resolution (HR) Coma Corrector Adaptor to T2 (M42x0.75mm) Adaptor to M48 (M48x0.75) Helical focuser
Five extension tubes from 30 to 5mm length with thread connection M48x0,75mm in a set. For adjusting different distances of the camera to the focal plane of the telescope or the corrector/field flattener. There is an M48.0,75 internal and external thread in each individual tube. The M48x0.75 thread is also called large T2 photo thread or 2.0 inch filter thread. Camera specific bayonet adapters or color and nebula filters can be used. Included are 5 different tubes with the steps 30, 20, 15, 10 and 5 mm. The larger free inner diameter of 45.0 mm effectively prevents undesired vignetting of the camera sensor. The outer diameter of the sleeves is exactly 50.65 mm and can therefore be mounted directly in any 2 inch diameter eyepiece adapter. FEATURES Extension sleeves M48x0,75 in set Five extension sleeves: 30, 20, 15, 10, 5 mm Use with correctors and field flatteners Distance adjustment from camera to focal plane Suitable for camera-specific bayonet adapters Also suitable for 2.0 inch colour and nebular filters Internal and external thread M48x0.75 mm (large T2 thread) Large inner diameter of 45.0 mm Outer diameter is 50.65 mm (2 inches) Black matt anodized aluminium Total weight 85 grams SCOPE OF DELIVERY Extension sleeves M48x0.75 (5 pieces)
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
The image plane of many telescopes is not plane, but curved. This results in a picture that has its optimal focus only in the center of the field of view - the edge of the field is out of focus and thus unsharp. The human eye is able to accomodate most of this but a camera will show stars that get increasingly unsharp towards the edge of the field. The Explore Scientific Multi Purpose Curvature Corrector eliminates field curvature in a variety of telescopes - Explore Scientific Apos and many other refractors and cassegrain telescopes. This increases the edge sharpness in the image drastically. Improves edge sharpness not only with Explore Scientific Apos, but also with many other refractor and cassegrain telescopes. This image field leveller fits all Nikon DSLR cameras, but can also be used for other camera types due to the universal T2 thread connection. This requires an optional camera-specific T2 ring. SPECIFICATIONSImage flattener for Nikon DSLR cameras Eliminates the field curvature of ED APO telescopes Can also be used for various cassegrains The image sharpness at the edge is drastically increased 2 inch/50.8mm push-in connector with filter thread T2 threaded connection (M42x0,75mm) Full multi-coating on all lens surfacesStainless steel housing Adapter for Nikon F bayonet included DELIVERY SCOPE Bildfeldebner Nikon (1 piece)
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
Camera specific bayonet adapter (camera ring) for Nikon DSLR with M48x0.75 mm internal thread for astrophotography. By using the large thread M48x0.75 mm, the vignetting of e.g. a DSLR full format sensor is effectively avoided. Compared to the small T2 thread M42x0.75, this adapter has a free inner diameter of 41.2 mm. This camera ring is made of matt black anodised aluminium and weighs only 30 grams. The light path (overall length) is 8.0 mm. FEATURES Camera-specific bayonet adapter NikonLarge female thread M48x0.75 mm Free inner diameter of 41,2mm No vignetting for full format sensors Light path (overall length) is 8.0 mm Made of matt black anodized aluminium Weight only 30 grams SCOPE OF DELIVERY Camera ring for Nikon (1 piece)
Converts the FL55SS into a high-performance astrograph The kit consists of a high-performance flattener lens, a reducer and the EX TUBE 66 connection ring, which was developed for the FL55SS Fluorite Apochromatic Refractor and improves photographic performance by dramatically flattening the surface.
Ultra-sharp image over the entire field of view of the DSLR full-frame sensor
The Flattener HD for the FL55SS reduces the change in the focal length of the FL55SS to a minimum and improves the evenness of the surface for prime-focus photography. The 44 mm image circle covers the entire field of view of a full-frame DSLR camera. When used in combination with the HD5.5 Reducer, the focal length is reduced by 0.79x (from f5.5 to f4.3) and the image circle retains a diameter of 44 mm, which significantly improves the sharpness across the entire field of view of DSLR cameras with a full-frame sensor.
96% light volume to the edge of the field of view
The Flattener HD was specially developed for the FL55SS refractor to reduce loss of light to a minimum across the entire 44 mm image circle of full-frame DSLR cameras.
Exceptionally high contrast
The same anti-reflective AS coatings used on our high-end VSD 100 f/3.8 astrograph are used to provide an outstanding light transmission of 99.9% per lens surface. Thanks to the matte black surface of the Reducer HD kit, loss of light, ghosting and scattered light and largely prevented.
FEATURES
Ultra-sharp image over the entire field of view
Designed for full-frame cameras
Illuminates 44 mm image circle
Cutting-edge AS coating
DELIVERY CONTENT
Flattener HD kit for FL55SS
66 mm extension tube
Dust caps
0.67x Focal reducer for ED/SD series The reducer decreases the focal length of the telescope, allowing you to takequick photos with shorter exposure times.Can be used with: ED/SD81S, ED/SD115S, ED/SD103SApplication: Reduces the focal length by a factor of 0.67x625-419 mm (f5.2) for ED/SD81S795-533 mm (f5.2) for ED/SD103S890-596 mm (f5.2) for ED/SD115SPrime-focus photography (APS-C)Distance to chip: 63.5 mmFEATURESReduces the focal length by a factor of 0.6760 mm connection thread625-419 mm (f5.2) for ED/SD81S795-533 mm (f5.2) for ED/SD103S890-596 mm (f5.2) for ED/SD115SDistance to chip: 63.5 mmWeight: 174 gDELIVERY CONTENT0.67x focal reducerDust caps
The neutral density filter transmits light uniformly across the entire
visual spectrum. It serves as an excellent filter to reduce glare and
irradiation when observing the Moon with any telescope 4"(10.2cm) and
larger. The ND96 filter may also be employed in the splitting of close
double stars where one of the binary pair significantly exceeds the
other in brightness.
Color Filter #ND96 Moon Filter (0.9 density; 13% transmission)
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 system enormously. Depending on the type of the celestial object, it is possible to dramatically increase the contrast by blocking annoying artificial light. The EXPLORE SCIENTIFIC UHC filter "zeros in" on the wavelengths of so-called emission nebulae. Those objects glow in special colours - their emission lines. Those emission lines are linked to chemical elements - in this case hydrogen at 486nm and 656nm, plus oxygen at 496nm and 501nm. The EXPLORE SCIENTIFIC UHC nebula filter blocks all other colour wavelengths (and thereby nearly all of artificial light) and only the emission line of the hydrogen and oxygen can pass the filter. The result is astonishing: suddenly nebulae are visible at locations that were completely invisible from, without filters. In suburban skies, for example the Owl-nebula M97, the Veil-nebula NGC 6992 or even the bright Dumbell-nebula M27 are not clearly visible. Using this filter allows you to see nebulae and their structures in much finer detail. A must for every visual observer.
The Explore Scientific nebula filters come with a individual test certificate - your guarantee to receive a premium filter.
This adapter replaces the M42x0.75 Adapter for CCD Camera that comes standard with the EXPLORE SCIENTIFIC 3-inch Field Flattener/0.7x Focal Reducer. Allows the connection of a camera via M48x0.75 thread. The larger free inner diameter than T2/M42 effectively prevents vignetting when using a full format camera. The illumination of the camera sensor is therefore optimised.FEATURESAllows the connection of a camera via M48x0.75 threadLarger free inner diameter than T2/M42No vignetting by using cameras with full frame sensor Fits to EXPLORE SCIENTIFIC 3" Flattener 0.7 x ReducerMade of black anodized aluminumSCOPE OF DELIVERYAdapter with M48x0,75 thread
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
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
£326.00*
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