No idea what the issue is. Go behind the scenes with Celestrons product development team and learn more about our award-winning and patented innovations. Performance wise what differences might there be using the reducer on a smaller scope. For me the Antares was a little brighter and had the least scatter by a bit so the better coatings won. This would tell us exactly how well aberrations are corrected. Sign up for OPT news, exclusive offers, and updates on the latest gear! The brightness, shape, and distortion of specific stars in the exact same position at the edge of the field was precisely identical in both reducers. CPWI has an extensive object database, employs PointXP mount modeling, and more. For both imaging and visual observing, these reducers also improve image sharpness at the edge of the field by correcting for coma and field curvature. Given the results of Test #1, I wanted to see if there was any truth to this assumption. Based on Test 1 and Test 2, I think there is perhaps more validity to opposing statements here in these forums that the Antares and current China-made Celestron do, indeed, have exactly the same optics just with different housings and branding. Explicitly designed for Celestron Schmidt-Cassegrain telescopes, this unique lens reduces your telescopes focal length and f/ ratio by 37%, turning your long focal length telescope into a fast, short focal length instrument. In such cases, we will be happy to take the item back as per our standard return terms. The EdgeHD .7x Focal Reducer Lens makes your EdgeHD 1100 one full F-Stop faster than f/10, reducing your exposure time by half to capture the same brightness of object . Please re-enable javascript to access full functionality. We do not price match competitors if they are out of stock. We will be glad to help. Increasing the operating distance, that is, moving a focal reducer away from the eyepiece or camera reduces its reduction factor, or conversely increases the amount of reduction. More important, its clear that the Antares is a reducer/corrector, just like the Celestron and not merely a reducer. For this test, I used a single configuration R/C, Click-lock, and 1.25 diagonal with the adapter. Clearly cost is a big factor for satisfied users. Normal shipments will resume on Monday, March 6, 2023. nleash the full pointing accuracy of your Celestron computerized telescope with a specialized telescope control software suite. . I have both the Antares and the Celestron reducers. Style: Observing the microscopic world has never been easier! For the best experience on our site, be sure to turn on Javascript in your browser. Practical Considerations of Focal Reducers, 4.2 Back Focus Requirements of Focal Reducers, GSO makes focal reducers for their line of Ritchey-Chretien, Celestron makes a series of focal reducers for the Edge HD line, 0.75x focal reducers for these telescopes, focal reducer for an 8-inch Celestron EdgeHD, A Primer on T-Rings and T-Adapters for Astronomy and Astrophotography, Choosing the Best Telescope for Beginners 2023, Top Night Sky & Astronomy Events in August 2022, Top Night Sky & Astronomy Events in July 2022, Selecting a Baader Planetarium Star Diagonal, A Guide to Choosing Astronomy Eyepieces for Binoviewers, Choosing a Magnifying Finder Scope for Your Telescope, A focal reducer will provide its design reduction factor only when it is placed at the exact working distance from the focal plane of the eyepiece or camera, Reducing the operating distance, that is, moving a focal reducer closer to the eyepiece or camera increases its reduction factor, or conversely reduces the amount of focal reduction. These scopes are compatibles with focal reducers. For this shoot-out, I used a standard Celestron C8 with Starbright coatings. Most focal reducers are designed to operate optimally at the working distance in the optical path to achieve their specified reduction factor, which is usually between 0.5x and 0.8x. The reducer fits all Meade and Celestron . My experience is that CN sellers are way above those listing elsewhere. Hence, there is a chance that you may not be able to thread your SCT diagonal or other SCT accessory on to this reducer for these or for any other brand. Its a good thing I have the super lube handy or my neighbors wont be happy with me.come to think of it, Im sure the small mammals here wouldnt be thrilled either! For example, the focal reducer for an 8-inch Celestron EdgeHD telescope has a design reduction factor of 0.7x and a specified working distance (or back focus) of 105mm. These reducers can also be used for visual observing with SCT scopes with eyepieces with a field stop as large as 24-27mm. As often noted in reviews and forum threads, Antares products tend to have threads that are a little less precise, and this specimen certainly demonstrated this. EclipSmart solar products feature Solar Safe filter technology providing the ultimate protection from harmful solar radiation, including both IR and UV light, and filters 99.999% of visible light. In both cases will end with a similar tfov. 2.2 Using a Focal Reducer at the Working Distance, 2.3 Adjusting the Reduction Factor of a Focal Reducer, 3.3 Focal Reducers for Compound Telescopes, 3.5 Focal Reducers for Ritchey-Chretien and Field Flattened Scopes, 3.6 Focal Reducers in 1.25" and 2" Barrel Formats, 4. Over the course of a several nights of general observing, I swapped back and forth between the Antares and Celestron R/Cs on a wide variety of objects open clusters, brighter galaxies, a couple of nebulae, and globular clusters as well. Housings, threads, reduction, correction, blah, blah, blah. In the 1960s, Celestrons founder, Tom Johnson, created groundbreaking new telescopes never before seen on the consumer market. However, even though the imprint on the item states "Reducer / Corrector" please note that his is a reducer only. The author finds differences in throughput and color balance, but then says he thinks the lenses are identical and he reaches his conclusions based on very long observing session. Orders placed over the weekend will be shipped on the following Monday. But is there a difference in quality between the Antares and the Celestron or Meade focal reducers? This focal reducer from Celestron reduces the effective focal length by 0.63X Enjoy the wider field of view & faster exposure times at f/6.3 with f/10 telescopes f/11 telescopes, such as the C14 will perform at f/7 The Celestron f/6.3 Reducer has four fully-multicoated elements Reduce your exposure times by a factor of 3! We tested GSO's 1.25" 0.5x focal reducer at a variety of operating distances and calculated the field of view through a telescope to derive the actual reduction factor that is plotted below. At least these two units I tested make the answer - whatever. Some refractors such the TeleVue Nagler-Petzval (NP), the Takahashi "FSQ", and the William Optics Redcat/WhiteCat 51 have inherently flat fields because of internal optical elements. I would pay slightly more for the Japan produced version, just because Hirsch was not bad either but sold it since I had 2 already. More aggressive reduction, or using these reducers with larger sensors, will result in aberrations and distortions near the edge of the image. Scope size might influence choice as well, as a C6 might benefit from the Antares' transparency, while larger scopes might benefit from the Celestron's higher contrast. Most refractor manufacturers such as William Optics, Tele Vue Optics, Explore Scientific, Sky-Watcher, William Optics, and Stellarvue make their own focal reducers optimized for use with their telescopes. It must be in stock at the time of Price Match for us to make a guarantee. The Antares FR2-0.7X is the same 4-element f/6.3 lens system used for f/10 Schmidt-Cassegrain telescopes but in a 2" barrel threaded for standard filters. In every configuration, there were essentially parfocal, requiring only a tiny fine focus adjustment when changing correctors. Meade once made an f/3.3 focal reducer for SCT scopes. And when used in some refractors, the field flattening is not as accurate as it is in the f/10 SCTs. and you will be fine. This also resulted in the clear aperture of the Antares being about 39-39.5mm, versus the Celestrons 41mm. Nebula Filters. Check out our 2022 telescope buying guide here! Focus misses by about 1 turnof the focus knob.Here is my solution:Buy a shorter 1.25 visual back for my scope. Looking forward to the day when I can do a shoot-out between a Japan and China Celestron, just for kicks. Optically, it consists of a four-element lens that is fully multi-coated for high contrast and resolution. * Not a Retail Store * 16313 Arthur StreetCerritos, CA 90703, USA, Availability: Item has been discontinued by Agena and we no longer carry this item. You also wont be unhappy spending the few extra bucks on the Celestron for the pretty orange lettering, particularly if you can pick one up used, as I did. It was used strictly for imaging, not visual observing. Never used one, but read the reviews here that suggest a coating problem. Sharpness is essentially the same. Again, to my surprise, there was absolutely no difference between the Celestron and Antares on any star. The camera side of the focal reducer is threaded for a T-adapter with wide M48 threads, or in some cases, with smaller M42 threads. This innovative software solves the time-consuming problem of trying to pinpoint the North Celestial Pole. I'd favor the Japanese Celestron version over the others that are commercially available. We reserve the right to verify a competitor's advertised price and the availability of the item. We only send interesting emails and will never sell your data. The lens has a knurled surface, providing a tremendous gripping surface for threading/unthreading. But while the image gets brighter, the size of the image circle gets proportionately smaller. Therefore, a 55mm back focus with a filter that is 3mm thick added to the imaging train would become 56mm. The Antares f/6.3 Focal Reducer for Schmidt-Cassegrain Telescopes is a low-price option for reducing the focal length of your Schmidt-Cassegrain telescope from f/10 to f/6.3. So Celestron buyers like Celestron, Meade buyers like the Meade and Antares buyer like the Antares. All rights reserved. From the SkyProdigy, a telescope so smart it can align itself, to our high-performance EdgeHD optical system, weve revolutionized the hobby of astronomy for beginners and advanced amateurs alike. InternetSales@optcorp.com. If you place your camera at a different working distance, you will get a different reduction factor and perhaps unwanted distortion in the image. Focal reducers for many SCTs and their flat-field equivalents usually have a back-focus distance of 105mm. But in the Japan version I have never noticed any anomaly like the ghosting in the China R/C. And, the reality is that every F/6.3 RC out there Celestron, Hirsch, Astromania, etc., etc. A reducer is a set of converging (or positive) lenses that cause the light from a telescope objective to converge at a steeper angle to the focal plane as if it were coming from an objective with a faster (lower) focal ratio and a shorter focal length. I have a Raspberry HQ camera, a Sony TV Zoom 12.5-75mm f1.8 and a Astromania 1,25" 0.5x focal reducer. He received his first telescope at the age of 5 and completed his first university course in astronomy at the age of 12, eventually receiving a master's degree in the subject. Once focused it's pretty good. However, manufacturers virtually never provide this specification. During checkout, you may also be shown other optional faster shipping choices.US Customers in Hawaii and Alaska: Free shipping applies to almost all products. For example, an 8" SCT without a focal reducer has an illuminated field of 38mm at 50% fall-off. They provide 0.75x focal reducers for these telescopes that takes an f/8 instrument down to f/6. Images in the Celestron tended to appear ever-so-slightly dimmer (maybe? Imagine having two telescopes in one a long focal length instrument for lunar and planetary work and a short focal length scope for deep sky observing and astrophotography. We have corrected # (iii) after equations 6 & 7. Thanks. Explore Scientific Keys to the Universe Sale, Antares f/6.3 Focal Reducer for Schmidt-Cassegrain Telescopes, Skip to the beginning of the images gallery. Hi. By While most Barlow lenses and focal extenders work with most kinds of telescopes available to amateur astronomers, focal reducers are designed to work in a narrow range of focal ratios of a telescope objective. USD $80.00. Using this same example of an 8" SCT and a 0.63x reducer, a visual observer can also enjoy brighter images and a wider field of view. Equation (4) shows the relationship between the distance d2 and the reduction factor MR. By using this site, you agree to our Terms of Use. Designed distancing using the reducer with a 1.25 visual back and 1.25 Televue mirror diagonal; Fumbling around in the dark, fine threads might be a problem. You can probably eke out 1.2 without noticing serious vignetting, which is a field stop of 31.5mm. As a result, the smaller tube may cut into the light cone and effectively reduce the working aperture of the telescope. Celestron's EdgeHD reducers feature a custom 5 element optical design engineered to maintain the flat-field performance of our award-winning EdgeHD optical system. Many reducers, such as the Celestron HD focal reducer mentioned above, and many focal reducers for apochromatic refractors, are meant to be used within a few millimeters (or less) of the specified working distance to achieve the best possible image results. I have this one Opticstar F6.3 Focal Reducer / Corrector. Download the Celestron PWI Telescope Control Software. The lens that the ZWO comes with give a perfect wide angle image of what is in front of it. I have an 8SE, and am thinking about getting a focal reducer. That means the base of the mounting threads of the focal reducer needs to be 55mm from the camera sensor to achieve the design reduction factor, which is usually 0.8x or 0.85x. It has only one cover, which surprised me. These reducers can also be used for visual observing with SCT scopes with eyepieces with a field stop as large as 24-27mm. An eyepiece with a 27mm field stop yields a true field of 1.03 in the C6 at f/10. A focal reducer does just the opposite of a Barlow lens or focal extender. 800-483-6287 Most reducers have a design reduction factor, MRD, that assumes the reducer is placed at a specific working distance, D, from the back surface of the focal reducer itself. In terms of reduction and correction which are what reducer/correctors are supposed to do both are superb. Quite interestingly it bears the very same engravings of the Meade 4000 r/c (including "series 4000") except for "MEADE". Field stop diameters are one of the specified specs of eyepieces. There is a way to make subjective data more useful and that way is proper blind, or better still. This article explains the basics of how focal reducers work with an astronomy telescope. Due to the design, the Reducer/Corrector lens does diminish a small amount of field curvature common to all Schmidt Cassegrain telescopes but does not eliminate it. All rights reserved. Can these economical focal reducers from GSO and other vendors result in good images? Sign up to receive sale alerts, news about upcoming celestial events, and telescope tips from our experts! Sign up for our newsletter to get exclusive deals, observing tips, and new product announcements. The faster f/ratio allows you to use slower film or shoot in lower light level situations and still properly expose your subject. Since the Celestron and Antares are supposed to have different focal lengths and spacing specs, I expected different results. Each focal reducer has a fixed specification called the working distance or required back focus. However, this also came at a cost, as the sky background in the Antares was slightly brighter. Even though the manufacturer did not specify the working distance or focal length of this reducer, it is easy to see from this plot that this item provides its stated reduction of 0.5x when it is placed at a working distance of 51.5mm between the base of the threads on the mount and the focal plane of the eyepiece or camera. GSO, for example, has a 0.75x reducer for RC scopes with a back focus of 80mm, which is usually enough room for a wide range of astronomy cameras and accessories and spacers as needed. The female end attaches to the rear cell of the telescope. No difference. As a Barlow's magnification increases with increasing distance from the Barlow, a focal reducer's reduction increases with increasing distance from the reducer. The Celestron f/6.3 is ~150 compared to the Antares at ~70. It was also a little brighter in the center of the field with subtle darkening in the outer 20% or so. As one increases, the other decreases. DUE TO EXTREMELY HIGH DEMAND, WE WILL NOT BE TAKING NEW ORDERS UNTIL MONDAY, DECEMBER 14. The Buyer's Guide To Eyepieces at the top of the Eyepieces forum has a column for this spec. SKU: CEL-94245. Learn more about extra solar planets imagery, 3D Star rendering, observation planning, telescope control, multiple-panel printing, and much more. It's an either/or proposition: reducer and 1.25", or 2", but not 2" and reducer. What I do know is that the Antares and the Celestron samples that I have perform exactly the same from the center right out to the edges. Product Details. ED stands for "extra-low dispersion," which refers to the composition and optical properties of the glass used for the lenses. With this telescope and this focal reducer, it does not help to move to a 2" eyepiece and a 2" diagonal as the visual view will be akin to looking through a porthole within the larger apparent field of view of the eyepiece. As another example,GSO makes focal reducers for their line of Ritchey-Chretien imaging telescopes. Depending on the design of the telescope, they may require separate focal reducers if they require focal reducers at all. You don't need to follow these equations to use a focal reducer, but they do show how the reduction factor changes with the placement of the reducer. Not a bit. riklaunim Members 559 3,445 Location: Poland Posted October 11, 2010 They are reported as identical. Powered by Invision Community. A few people have reported issues with the male SCT thread diameter on this item being a bit larger than necessary. He also holds a Ph.D. in engineering physics from McMaster University. Whereas the Celestron threaded smoothly onto the scope, the Antares chattered and squeaked a bit more so when being removed. I use it on my C8 SCT with a 1000d, and it seems to do everything written on the tin. The working distance or required back focus, explained above, is usually specified and is far more important in practice. Focal Reducer, 2", 0.7X. It's important to match the back focus to within a millimeter or two to get an optimal image, especially with cameras with larger sensors. For example, a 0.8x reducer placed at the working distance provides a reduction of (1 0.8) x 100 = 20%. Planetarium software package which provides easy-to-understand explanations and impressive visuals of all kinds. It might work but it does not tell us anything about how well or to what extent the product works to correct the field of an SCT. At a significantly lower price point, the Antares is a steal, and theres no need to upgrade to the Celestron if you already have one. First, I wanted to compare the actual reduction provided by these competitors, as many threads here cite different ideal spacing from the reducer to eyepiece focal plane to achieve the correct f/6.3 result. Explore Scientific - Keys to the Universe Sale. If a stronger level of focal reduction is used, say 0.5x, then the image circle may be too small to fill the sensor of larger cameras. - thanks. The internal surfaces are blackened and glare-threaded to provide the highest contrast. Completely stuck, completely frustrated. Unique focal reducer and field corrector lens accessory, Reduces the focal length and f/ ratio of your Schmidt-Cassegrain telescope by 37%, Provides a dual focal ratio instrument, without sacrificing image quality, Compatible with all Schmidt-Cassegrain telescopes (see compatible list in description). Wonder how they would stack up with a Japanese 6.3. OPT Product Number: AE-SCTFR specifications Warranty 2 Year Warranty Works as advertised! How does it look thats what matters. Wow, that is a very detailed discussion! For the best experience on our site, be sure to turn on Javascript in your browser. Brian Ventrudo is a writer, scientist, and astronomy educator. The most commonly available focal reducers for SCTs are the f/6.3 reducers from Celestron and a similar f/6.3 focal reducer from Meade. This fully multi-coated lens provides maximum light transmission with near full-field illumination. Thanks guys, I'm trying to get my ZWO ASI120MC-S to work with my 90mm Meade. The Best Dedicated Astronomy Cameras for Beginners, Astronomik OIII 12nm CCD Filter - T-Threads, Pegasus Astro Dual Motor Focus Controller, 10 Micron 12kg (26.45lbs) Stainless Steel Counterweight- GM 2000, I would like more information regarding stock availability dates. In this configuration, the 29.5mm camera nosepiece and a 6mm extension ring positions the reducer at a working distance of 53.5mm from the camera sensor, which is located 12.5mm inside the front edge of the camera. But I am rusty, can you condense a bit for me please? Your eyepieces are the first accessories you should learn to use with your telescope. Please Log in to save it permanently. So ab6110 is asking for a FR only without coma correction, there are a couple of brands who make special reducers for the ACF.
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