Focal Reducers | Celestron These reducers can also be used for visual observing with SCT scopes with eyepieces with a field stop as large as 24-27mm. It's highly unlikely that they could be so precisely identical unless they were. This is the distance at which the reducer must be placed in front of the eyepiece or camera focal plane in order to operate at the design reduction factor. because they really dont matter. But is there a difference in quality between the Antares and the Celestron or Meade focal reducers? 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. The review is a subjective visual impression, which is interesting but not best evidence. Still not sure what is the right gear for you? That includes, for example, a 1.25" eyepiece with an apparent field of view of 68 and a focal length of 24mm (eg. Just one question. I don't know. I only have the Celestron f/6.3. If you are using a camera that has a back focus of less than 55mm, additional spacer rings will be required between the reducer and the camera. Explore Scientific - Keys to the Universe Sale. No retailers currently carry this product. CPWI has an extensive object database, employs PointXP mount modeling, and more. Antares f/6.3 SCT Focal Reducer - Rother Valley Optics Ltd Edited by bluewater, 05 September 2020 - 11:27 AM. JavaScript seems to be disabled in your browser. First, let's have a look at some key optical parameters are needed to understand focal reducers. However I've also read that the back focal distance on the Celestron is 105mm while the Antares is 81mm so they couldn't be identical. 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. The faster f/ratio allows you to use slower film or shoot in lower light level situations and still properly expose your subject. One problem with getting opinions is that most of use do not have both reducers or have never done a side by side comparison. Please note, orders placed after 10am on 2/28/2023 will be delayed. It threads onto the rear cell of 5" to 16" Celestron and Meade Schmidt-Cassegrain telescopes, making it possible to have a dual focal ratio instrument without sacrificing image quality. 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. The internal surfaces are blackened and glare-threaded to provide the highest contrast. Using an eyepiece with a 27mm field stop with the reducer will illuminate the edge the same as using an eyepieces with a 42.9mm field stop without it. Keep in mind that these differences were very subtle, and could be due to normal variations in coatings among different runs, and not necessarily unique to the brands. Wow, that is a very detailed discussion! Also read the reviews here, including those at 4 stars. 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. 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. 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. 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. They only publish the value of D, the working distance (sometimes called the back focus distance) and the design reduction factor MRD. Is there likely to be any differences in performance between using these on an 8 or something smaller like my 6SE? Therefore, a 55mm back focus with a filter that is 3mm thick added to the imaging train would become 56mm. Both exhibited consistent reduction, identical field flattening, and edge correction properties, and both were high quality optically and mechanically. Looking forward to the day when I can do a shoot-out between a Japan and China Celestron, just for kicks. All Rights Reserved. These reducers have a back focus (or design working distance) of 80mm. 2023 OPT Telescopes. These reducers can also be used for visual observing with SCT scopes with eyepieces with a field stop as large as 24-27mm. Celestron Focus Motor for SCT, EdgeHD & 8" RASA, Celestron C6 0.63 reducer/flattener back focus. For the best experience on our site, be sure to turn on Javascript in your browser. 0.63x Starizona Focal Reducer for SCTs- Awesome Astrophotography Focal Reducer, 2", 0.7X - Antares No results, please adjust your filters. The Reducer/Corrector can also be used for terrestrial digiscoping. 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. M44 was a perfect target for this, as its large size maxes out the FOV on a C8 with a corrector, and its bright stars make great targets for measuring the very edge of the visible field. No difference. It is not a corrector or flattener. If yes, what kind of focal reducers can I use? This was most noticeable on the eyepiece end of the RC, where the metal rim surrounding the lens was about 1mm thicker than on the Celestron. 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). I have both the Antares and the Celestron reducers. Unleash the full pointing accuracy of your Celestron computerized telescope with a specialized telescope control software suite. Please let us know what topics you are interested in. 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. 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. Unlike . With the barrel 1.25 reducer won't focus, all I get is fuzzy snowballs. This filter threads on to the rear cell of your Celestron or Meade SCT telescope. USD $80.00. I have a made in Japan 6.3 R/C and a made in China 6.3 R/C. Does anyone have any experience with the Celestron and Antares focal reducers? Watch this before you buy Celestron 8SE SCT, or a Focal Reducer or a Thanks Peter! Does anyone know if the Antares 4000 focal reducer is as good as the Celestron focal reducer. Never used one, but read the reviews here that suggest a coating problem. A former wireless communications consulting engineer and management consultant to various Fortune 500 companies, Manish started Agena AstroProducts in 2003. However, some focal reducers can be used on other models of telescopes, but this is not always possible. In both cases will end with a similar tfov. For imagers, the main purpose of a focal reducer is to increase the brightness of the image at the focal plane. This would tell us exactly how well aberrations are corrected. Focus misses by about 1 turnof the focus knob.Here is my solution:Buy a shorter 1.25 visual back for my scope. I would not use the reducer with a 2" diagonal or eyepiece in the C6. Ive owned Celestron, Meade, and Antares models over the years at least a couple of each. I think there may be some confusion here, because Antares makes a variety of reducers for eyepieces and scopes in addition to this SCT R/C but this definitely is a reducer/corrector. The equations in the Appendix show how this all works. (Note: Using the simple equations above, the focal length of this reducer can be estimated to be about 350mm). I've seen some older threads saying that the Celestron, Meade and Antares FRs are all the same and manufactured in the same factory. Celestron Nexstar+ 127 SLT, several budget plossl eyepieces, Celestron 8-24mm zoom EP and a 12.5mm illuminated double reticle EP, Svbony SV205 camera w/.5 focal reducer, Celestron SkyMaster 20x80 binos on a 40 yr old QuickSet PanHead tripod, Stellarium, Sharpcap and ManyCam on my laptop, SkyView and Nightshift on my phone and a dandy little $9 . Copyright 2021 Stargazers Lounge InternetSales@optcorp.com, 800-483-6287 Can you help me? We do not price match competitors if they are out of stock. In terms of reduction and correction which are what reducer/correctors are supposed to do both are superb. CEL-94245. SKU: CEL-94245. Anyway, when purchased my R/C the "original" Celestron unit was not readily available and was offered instead the one sold under the shop's own label (in my case Tecnosky, but I saw the same product offered under TS label). Hi. That was fun. 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. Much to my surprise, swapping back and forth between the two correctors using all three diagonal configurations, I also could detect absolutely no change in reduction between the two reducers. Powered by Invision Community. In most cases, the easiest option is to choose the focal reducer made specifically for your telescope. Orders placed over the weekend will be shipped on the following Monday. ), ASI Air Plus - Connected items are 'greyed out', Cost of ordering used equipment U.S. - Can can more than double figure, Tuthill Isostatic Mount and Star Trap Power Module. Generally, views through the Antares seemed a little more transparent and brighter. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. The design reduction factor of a focal reducer is the relative amount by which the effective focal length of the telescope is reduced when the focal reducer is used at its specified working distance or back focus. Designed distancing using the reducer with a 1.25 visual back and 1.25 Televue mirror diagonal; Perhaps not exactly- there will be some uncertainty because of manufacturing tolerances and so forth, but it will be close. 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. They are designed (assuming you are referring to the f/6.3 version) for the f/10 light cone. When the camera sensor is placed at this distance, the reduction factor of these reducers is 0.75x. Since the focal length of the reducer, FR, is fixed, as d2 increases then MR decreases. You attach the focal reducer to the rear port on a SCT and can keep it covered. Easy solution found a very tiny dab of super lube on the threads and all was well and quiet. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. 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. We have placed cookies on your device to help make this website better. If you place your camera at a different working distance, you will get a different reduction factor and perhaps unwanted distortion in the image. Download the Celestron PWI Telescope Control Software. The new Lithium Phosphate (LiFePO4) battery chemistry has significant advantages over other battery chemistries, great for for those Astronomers on the go. - thanks. As a real-world example plot showing the above relationships, let's look at the 1.25" GSO focal reducer that provides a design reduction factor of 0.5x. 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. Reducer - Corrector | Celestron Please Log in to save it permanently. Even though they may have been slightly dimmer, galaxies were a bit easier to tease out of the urban light soup I deal with. 2023 Celestron, LLC. Assuming you use the reducer with the stock 1.25" diagonal, it will operate at f/6.3. Does anyone know if the Antares 4000 focal reducer is as good as the Celestron focal reducer. Given past experience with them, I decided not to include the Meade version in my little experiment, as I have never met one I liked from getting one of the too-short focal length models, to one with some overflow cement in the doublet, to focus difficulties with some eyepieces. Most amateur astronomers are familiar with a Barlow lens (or a focal extender), a negative or diverging lens that effectively increases the focal length and the focal ratio of a telescope's objective lens. * Not a Retail Store * 16313 Arthur StreetCerritos, CA 90703, USA, Availability: Item has been discontinued by Agena and we no longer carry this item. Focal reducers for refractors are easy to use. Field stop diameters are one of the specified specs of eyepieces. 2. Celestrons aplanatic EdgeHD optics revolutionized astroimaging. The working distance (backfocus) of the Celestron f/6.3 reducer is specified to be 105mm from the base of the male SCT thread on the camera side. I have the Japanese version and although I haven't used it in quite awhile, the views through it were superb with no internal reflections at all. How about for visual observers? The focal length and design working distance for this focal reducer were not available from the manufacturer. Celestron Reducer Lens .7x - EdgeHD 925 The EdgeHD .7x Focal Reducer Lens makes your EdgeHD 925 one full F-Stop faster than f/10, reducing your exposure time by half to capture the same brightness of object 5-element lens design Maintains similar. 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. However, even though the imprint on the item states "Reducer / Corrector" please note that his is a reducer only. The easiest way to use a focal reducer is to make sure you place it at the specified working distance in front of your camera or eyepiece. Request stock alerts and we'll let you know when the item is back in stock. Another factor to consider: focal reducers also increase the angle at which light approaches the focal plane. I think that the FRs made in Japan in the day may have been better. Hello! a Tele Vue Panoptic), or a Plossl eyepiece with an apparent field of view of 50 and a focal length of 32mm. F 6.3 focal reducer/corrector. - Discussions - Stargazers Lounge Celestron or Antares? An eyepiece with a 27mm field stop yields a true field of 1.03 in the C6 at f/10. In this case, d2 = FR/2, which means the back of the focal reducer is located at a distance FR/2 from the camera or eyepiece. Michael 1 ronin Members Style: With both, using the same diagonal set-up, the exact same stars were visible at the very edge of the FOV. Wonder how they would stack up with a Japanese 6.3. InternetSales@optcorp.com. Read our 101 article or get in touch. Contiguous US Customers:All items we sell ship for free within the Contiguous US. Better images are also obtained when using these focal reducers at a reduction factor of 0.5x 0.8x, approximately. My experience is that CN sellers are way above those listing elsewhere. 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. Have always disliked the crude, noisy SCT threads, but I get it. 800-483-6287 Focal reducers are essential optical accessories for astrophotography, electronically-assisted astronomy (EAA), and in some cases, for visual observation with long focal ratio telescopes. Reviews. Unscrew that wide angle lens and put it away, then attach the ASI120 to the nose-piece that came with the camera and fit that into the eyepiece holder. Get ready for a night of astroimaging with your mount faster than previously thought possible with All-Star Polar Alignment. Imaging - Focal Reducers and Flatteners - Page 1 - KW Telescope So, if you have a filter that is 3mm thick, you need to add 1mm of spacing to your imaging train to retain the correct back focus. They never really recovered from selling a few 15 years back with element reversed. Figure 6 shows a 1.25" focal reducer from GSO configured with a ZWO ASI224MC camera. Many focal reducers are meant to be used within a few millimeters of the specified working distance to achieve the best possible image results. I wish there was. With the Celestron Reducer/Corrector Lens, thats precisely what you get. Great for home, classroom, or home-school use, this kit includes all the essential items youll need to begin exploring the wonders of the microscopic world. However, the China 6.3 R/C has noticeable internal reflections that I haven't figured out yet. In the 1960s, Celestrons founder, Tom Johnson, created groundbreaking new telescopes never before seen on the consumer market. Focal reducers for these relatively fast ED refractors are generally for imaging only, not for visual observation. One focal reducer will not achieve optimum results with all types of telescopes, so there is no universal' focal reducer. How does it look thats what matters. 3. The C8 has no noticeable vignetting with a 32mm Plssl in the f/6.3 reducer. Theres a long-running debate in these forums and even statements from some reputable dealers that the Antares is just a reducer (even though it is labeled Reducer/Corrector), whereas the Celestron is a true R/C, which flattens the SCTs naturally curved field and provides some edge correction.