Celestron Focus Motor for SCT, EdgeHD & 8" RASA, Celestron C6 0.63 reducer/flattener back focus. Getting the proper back-focus for your imaging camera is a vital step in getting the best data possible out of your telescope imaging/research rig. Meade once made an f/3.3 focal reducer for SCT scopes. Nada. As I understand it, compared to the old Meade SCT's, the ACF is already "coma corrected", so the standard Meade, Celestron etc F6.3 focal reducers are not suitable and will only worsen the images. Whereas the Celestron threaded smoothly onto the scope, the Antares chattered and squeaked a bit more so when being removed. It must be in stock at the time of Price Match for us to make a guarantee. Can you help me? Using one on such a scope would make demands on the eyepiece design and increase the exit pupil to an extent that focal reduction on fast Newts is not practical. If yes, what kind of focal reducers can I use? Reducer - Corrector Learn More. 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 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. looks virtually identical, except for the lettering. The working distance or required back focus, explained above, is usually specified and is far more important in practice. because they really dont matter. 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. As mentioned in Section 2.3, the reduction factor for these focal reducers can be varied by adding spacers to move the reducer further from the camera sensor or eyepiece. All Rights Reserved. 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). When the camera sensor is placed at this distance, the reduction factor of these reducers is 0.75x. - thanks. 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. 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). USD $80.00. If I had to chose one, I would base my decision on your level of light pollution perhaps the Antares for its slightly higher transmission if you live under less light polluted skies, but the Celestron for its greater contrast if you are dealing with a suburban or urban light dome. I also used several eyepieces including the ES 24mm/68, 17.5mm and 12.5mm Morpheuses, and a 10.5mm Pentax XL. Torazz This rugged, 3-in-1 device features a true tactical 3-mode flashlight, a hand warmer, and a portable power bank for recharging your personal electronics on the go. You attach the focal reducer to the rear port on a SCT and can keep it covered. Such an image circle is still large enough to encompass the relatively large sensor of many deep-sky astronomy cameras. It is not a corrector or flattener. Product Details Antares' f/6.3 focal reducer provides a faster f/6.3 system for imaging or visual use when used with an f/10 SCT or other compatible telescopes. The Celestron f/6.3 is ~150 compared to the Antares at ~70. Well done. I use the same back spacing for both on a small 6" Celestron SCT. For Ritchey-Chretien telescopes such as those manufactured by GSO, there are also dedicated focal reducers with a reduction factor of 0.7x to 0.8x. Very helpful, thanks a lot for this article! Optically, it consists of a four-element lens that is fully multi-coated for high contrast and resolution. The reducer fits all Meade and Celestron . As one increases, the other decreases. The lens is housed in machined aluminum for are machined aluminum black anodized. I don't know. a Tele Vue Panoptic), or a Plossl eyepiece with an apparent field of view of 50 and a focal length of 32mm. However, these will not impact optical performance. Stock focusers in an SCT move the mirror of the scope to change the position of the focal plane, and they have sufficient travel to accommodate a focal reducer. The focal length of a focal reducer is usually measured from the rear lens surface of the reducer (and not the reducer's housing). 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 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. 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. Most different was that the sky background was a little darker and more uniform, providing a tiny contrast boost for fainter objects. It was used strictly for imaging, not visual observing. It works fine but you should stick with 1.25 EPs; or can use 2" EPs without corrector. 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. Orders placed over the weekend will be shipped on the following Monday. But the smaller image circle means there is a limit to the field stop of an eyepiece that can achieve an unvignetted image. Stars had a tiny bit more sparkle and pop. Download the Celestron PWI Telescope Control Software. Several functions may not work. Imaging - Focal Reducers and Flatteners - Page 1 - KW Telescope How about for visual observers? They both are great and I doubt my eyes could detect a difference in any one of them including the Japan version. 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. 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. Theoretically each of these combinations all varied-length light paths should have resulted in slightly different reductions between the Celestron and Antares, since they supposedly have different focal lengths. The same illumination you have at the edge of a 27mm field, the C8 has at the edge of a 38mm field. When you said, "in some cases" a focal reducer also works as a flattener/corrector, are you saying that not all focal reducers are flatteners/corrector? Completely stuck, completely frustrated. Focal reducers for these relatively fast ED refractors are generally for imaging only, not for visual observation. They never really recovered from selling a few 15 years back with element reversed. In some cases, focal reducers also act as field flatteners by correcting for field curvature and coma of the objective lens. Explore Scientific - Keys to the Universe Sale. OPT Product Number: AE-SCTFR specifications Warranty 2 Year Warranty Works as advertised! Today, our world-class team of optical and electronic engineers continues to push the boundaries of technology. Here, there was a subtle difference . ED stands for "extra-low dispersion," which refers to the composition and optical properties of the glass used for the lenses. That includes, for example, a 1.25" eyepiece with an apparent field of view of 68 and a focal length of 24mm (eg. Focal Reducer for SCT - ACF - Stargazers Lounge Manish holds a Master's degree in Electrical Engineering from Virginia Tech and an MBA from the Kellogg School of Management at Northwestern University. I have the Antares and have no complaints. StevieDvd Members 1,182 1,812 Location: Stevenage, UK Posted March 9, 2021 (edited) Don't know but your welcome to try out my Meade 6.3 sct reducer next time you are passing. Field stop diameters are one of the specified specs of eyepieces. Can you tell me about the use of reducers in Maksutov-Cassegrain telescopes? Focal reducers (and focal reducer/field flatteners combos) are usually used with two types of telescopes, refractors and compound telescopes such as Schmidt-Cassegrain or Ritchey-Chretien. Upon close inspection, it was clear that the housing of Antares assembled in Canada version was a little more substantial than the Celestron. Reducer Lens .7x - EdgeHD 925 Learn More. I've only used it a few times but it looks good to me. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. They only publish the value of D, the working distance (sometimes called the back focus distance) and the design reduction factor MRD. When using the diagonal, keep the field stops of the eyepieces under 20mm. Using these numbers in equation 4 in the Appendix, below, we can easily calculate that the focal length of this unit is approximately103mm (it will be 103mm plus the small amount by which the rear lens surface of the reducer is recessed beneath the reducer housing). Advanced designs for Schmidt-Cassegrain scopes such as the Meade ACF or Celestron Edge HD have optical elements in the tube to correct for coma and field flatness. Your eyepieces are the first accessories you should learn to use with your telescope. 800-483-6287 I think I remember hearing the reduction factor is slightly different, cant remember more or less reduction. Meade and Celestron both sell such SCT-T adapters with the correct optical length. If the focal reducer is to be used for visual observation, the visual back is threaded onto the eyepiece side of the reducer, and then a star diagonal and eyepiece are installed as usual. Details: The item must be the identical item, brand name, size, weight, color, quantity and model number. Start Chat Focal Reducer, 2", 0.7X. If you do so, you will achieve the design reduction factor. Focal reducers for many SCTs and their flat-field equivalents usually have a back-focus distance of 105mm. Also read the reviews here, including those at 4 stars. This standard distance is a consequence of the design of DSLR cameras for which the distance of the sensor to the outer edge of the flanges is about 45 mm, while the T-ring that attaches to the flange for astrophotography is about 10mm thick. 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. That's partly because focal reducers correct for field curvature, which itself depends on the focal ratio and other optical design factors of the telescope. If it's positioned further from the eyepiece or camera and closer to the telescope objective, the reduction factor increases. 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. Quite interestingly it bears the very same engravings of the Meade 4000 r/c (including "series 4000") except for "MEADE". ), but stars seemed a bit tighter and their colors were richer and more dramatic. Not a bit. This article explains the basics of how focal reducers work with an astronomy telescope. In every configuration, there were essentially parfocal, requiring only a tiny fine focus adjustment when changing correctors. Some coma is visible in the corners, but the image is quite good for EAA applications. The Buyer's Guide To Eyepieces at the top of the Eyepieces forum has a column for this spec. F 6.3 focal reducer/corrector. - Discussions - Stargazers Lounge DUE TO EXTREMELY HIGH DEMAND, WE WILL NOT BE TAKING NEW ORDERS UNTIL MONDAY, DECEMBER 14. At least these two units I tested make the answer - whatever. For example, with a 0.8x focal reducer, a telescope with a focal length of 800mm will operate at 800 x 0.8 = 640mm when the reducer is placed at the working distance specified by the manufacturer. The lens has a knurled surface, providing a tremendous gripping surface for threading/unthreading. JavaScript seems to be disabled in your browser. When placed in the focal plane in front of a camera or eyepiece, a focal reducer leads to a wider field of view and a brighter image of extended objects, which is important for reducing the exposure times when imaging faint extended objects like nebulae or galaxies. If the reducer is placed elsewhere, at a position called the operating distance, the focal reduction factor will not be as advertised. In your opinion, is the Celestron is worth the added cost ($150 vs. $90)? If the reducer is placed closer to the eyepiece or camera than the distance D, the reduction factor decreases. Place the plastic covers on the lens when not in use to reduce the dust collection. No small animals were harmed in making these observations. I really don't see any difference in the current crop except the "Meade" is usually the cheapest. Never noticed any anomalies with this unit. 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 . Reducer Lens .7x - EdgeHD 800 It seems right to put some distance between the camera and the focal reducer, right? 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. The reducer features fully coated optics in an anodized aluminum filter ring with an ergonomic rubber grip. No experience with the Antares reducers, but I haven't personally seen a difference between Celestron and my current pair of made in Japan Meade reducers. Since 2008, Brian has taught astronomy to tens of thousands of stargazers through his websites OneMinuteAstronomer.com and CosmicPursuits.com. None of this was offensive, nor did it interfere with views in any significant way. WiFi technology encircles the globe in a web of connectivity, knowledge, and information. As mentioned in Section 2 of this guide, the reduction factor of a focal reducer depends on its position in the optical path relative to the eyepiece or camera. Never used one, but read the reviews here that suggest a coating problem. No results, please adjust your filters. So ab6110 is asking for a FR only without coma correction, there are a couple of brands who make special reducers for the ACF. 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. For example, many focal reducers designed for f/7 or f/8 ED refractors such as those from Tele Vue, William Optics, Sky-Watcher, and Meade are designed to have a working distance (or back focus) of 55mm. On the trail, at the job site, in the classroom, or simply sitting at home relaxing the Celestron Elements ThermoTank 3 will keep your hands toasty. 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. . 160K views 9 years ago This video is a complete overview of focal reducers and how they function applying to telescopes. I only have the Celestron f/6.3. As a result, the smaller tube may cut into the light cone and effectively reduce the working aperture of the telescope. Focal reducer for 8SE - Celestron vs. Antares - Cloudy Nights An f/6.3 reducer is designed to reduce the focal ratio of an f/10 SCT to f/6.3. The designed reduction factor (0.5x in the case of the GSO reducer example above) should be considered a rule of thumb or approximate value in most cases, rather than a very precise number. This should not be the case if they have their purportedly different focal lengths. Explore Scientific Keys to the Universe Sale. Specially-designed focal reducers are available for use with these telescopes. The focus barely shifts between filters and I suspect any shifts I do get are down to the filters and changes in temp. Our proprietary StarBright XLT optical coatings dramatically increase transmission, up to 97.4% on our Schmidt corrector lenses. They usually have a 2" barrel that slides into the telescope focuser. InternetSales@optcorp.com. I had a Celestron, Antares and Hirsch for awhile and compared them over about a year. Enter it during checkout! The review is a subjective visual impression, which is interesting but not best evidence. This telescope control software replaces the hand control and allows the user to remotely control their Celestron computerized telescope from their personal PC or laptop. With spring galaxy season here, I decided to pick up a couple more to compare in a head-to-head shoot out. Reducer Lens .7x - EdgeHD 1100 - Celestron He also holds a Ph.D. in engineering physics from McMaster University. No difference. One problem with getting opinions is that most of use do not have both reducers or have never done a side by side comparison. Both exhibited consistent reduction, identical field flattening, and edge correction properties, and both were high quality optically and mechanically. Focal reducers for SCT, RC, and field-flattened Edge HD or ACF telescopes thread onto the back of the telescope tube with 2"-24 or 3"-28 SCT threads. 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. Please re-enable javascript to access full functionality. We reserve the right to verify a competitor's advertised price and the availability of the item. Focal Reducers | Celestron Easy solution found a very tiny dab of super lube on the threads and all was well and quiet. What is likely is that fatigue sets in, and also that as the targets move toward or a way from the meridian there will be changes for that reason alone. . In terms of reduction and correction - which are what reducer/correctors are supposed to do - both are superb. Possibly the design of the Antares was changed .. Right off the bat, I was struck by how similar the two R/Cs were. Since then, Agena has become one of the leading online retailers of telescopes and astronomical accessories worldwide. Thanks for any advice or experience you could share. 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. A few people have reported issues with the male SCT thread diameter on this item being a bit larger than necessary. Each focal reducer has a fixed specification called the working distance or required back focus. Another factor to consider: focal reducers also increase the angle at which light approaches the focal plane. We will be glad to help. Antares' f/6.3 focal reducer provides a faster f/6.3 system for imaging or visual use when used with an f/10 SCT or other compatible telescopes. Sharpness is essentially the same. More aggressive reduction, or using these reducers with larger sensors, will result in aberrations and distortions near the edge of the image. All Rights Reserved. However, it will not thread into William Optics accessories, and with GSO it is a hit or miss. Celestrons award-winning Nature DX binocular gets a major upgrade with the addition of ED objective lenses. If you want to use them for visual - try maybe long focal length eyepieces rather than the reducer. Therefore, a 55mm back focus with a filter that is 3mm thick added to the imaging train would become 56mm. I have this one Opticstar F6.3 Focal Reducer / Corrector. Hello! This innovative software solves the time-consuming problem of trying to pinpoint the North Celestial Pole. But in the end they both do pretty much the same thing and it sounds like any performance difference is subtle. In some cases, focal reducers also act as field flatteners by correcting for field curvature and coma of the objective lens. However, this also came at a cost, as the sky background in the Antares was slightly brighter. The threads were similar on the eyepiece end, but a bit smoother. Does anyone know if the Antares 4000 focal reducer is as good as the Celestron focal reducer. It can also be used with any other small chip CCD camera having a 1.25" nosepiece, such as the Celestron NexImage, Meade DSI . Optically, it consists of a four-element lens that is fully multi-coated for high contrast and resolution. Focal Reducers - Complete Overview and Function - YouTube The working distance of the GSO 0.5x focal reducer with 1.25" barrel and the GSO 0.5x focal reducer with 2" barrel is about 51mm to 53mm, approximately, from the middle of the metal cell that holds the lens. This focal reducer is made to attach to the rear cell of Schmidt-Cassegrain or Maksutov-Cassegrain telescopes. I've seen some older threads saying that the Celestron, Meade and Antares FRs are all the same and manufactured in the same factory. 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. But in the Japan version I have never noticed any anomaly like the ghosting in the China R/C. For me the Antares was a little brighter and had the least scatter by a bit so the better coatings won. My application is mostly visual now, but I'm looking to do more astrophotography over time. It's highly unlikely that they could be so precisely identical unless they were. F6.3 Focal reducer for F/10 or higher telescopes, 43mm aperture, 4-Element, Fully Multicoated. It has only one cover, which surprised me. I even lost track of which reducer I was using. 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 focal length and design working distance for this focal reducer were not available from the manufacturer. 0.5X focal reducer for Celestron, Meade, and Orion CCD imaging cameras The C8 has no noticeable vignetting with a 32mm Plssl in the f/6.3 reducer. ED glass is specially formulated and contains rare-earth compounds that greatly reduce a visual defect called chromatic aberration. Thanks for the extremely valuable article. 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. 2023 OPT Telescopes. Have a promo code? Celestron Solar Safe filter technology is GUARANTEED SAFE for direct solar observation and has been independently tested by SAI Global Assurance Services. Reducer Lens .7x - EdgeHD 1100. Watch this before you buy Celestron 8SE SCT, or a Focal Reducer or a Hyperstar 7,758 views Mar 28, 2018 145 Dislike Share Ray's Astrophotography 42.3K subscribers Note: I am not paid or. We only send interesting emails and will never sell your data. Add a 0.63x reducer, and the brightness of extended objects increases by (1/0.63)2 = 2.5. One of the most important factors in a telescope is its transmissionthe percentage of light that reaches the focal plane. They provide 0.75x focal reducers for these telescopes that takes an f/8 instrument down to f/6. Figure 2 shows the effective of a focal reducer on the light from a telescope objective. 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. Michael 1 ronin Members The Reducer/Corrector is easy to install by threading the unit onto the rear cell of your Schmidt-Cassegrain telescope (or the reducer plate of the C11 and C14). These scopes are compatibles with focal reducers. Reproduction without permission prohibited. Clearly cost is a big factor for satisfied users. You need to be a member in order to leave a comment. However, the export of some items may be restricted outside the US due to size or manufacturer restrictions. However, because the field curvatures in refractors and SCTs vary a lot, I would predict unpredictable effects inre: field curvature. This would tell us exactly how well aberrations are corrected. Sky recognition technology that has revolutionized the manual telescope by eliminating the confusion common among beginners and enhancing the user experience for even seasoned telescope users.
How Do Virgos Act When They Are Jealous,
List Of Jack Nicklaus Caddies,
What Happened To Fox 17 Weatherman,
Gene Kelly Producer Band Of Brothers,
Whale Shark Lifespan In Captivity,
Articles A
antares vs celestron focal reducer