If you want to use them for visual - try maybe long focal length eyepieces rather than the reducer. Explore Scientific Keys to the Universe Sale. I really don't see any difference in the current crop except the "Meade" is usually the cheapest. Copyright 2021 Stargazers Lounge * Not a Retail Store * 16313 Arthur StreetCerritos, CA 90703, USA, Availability: Item has been discontinued by Agena and we no longer carry this item. This focal reducer and field flattener consists of a four-element multicoated 40mm lens in a metal cell. Easy solution found a very tiny dab of super lube on the threads and all was well and quiet.. None of this was offensive, nor did it interfere with views in any significant way. The key points are as follows: So just remember that a smaller distance (from the camera or eyepiece) means a lower amount of reduction (and vice versa). I focus using a moonlight electronic focuser and focusmax. That is definitely a 2" eyepiece, but it is not a large or long focal length 2" eyepiece. Thanks for pointing this out. For Stephen Wilkerson: The ZWO ASI120MC-S does come with a wide angle lens, HOWEVER, it is NOT intended to used when you are using the ASI120 camera attached to your telescope. A useful thing to know is how far from the objective lens (for a refractor) is the focal reducer located. 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 . Go behind the scenes with Celestrons product development team and learn more about our award-winning and patented innovations. 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. They never really recovered from selling a few 15 years back with element reversed. Sign up for our newsletter to get exclusive deals, observing tips, and new product announcements. The threads were similar on the eyepiece end, but a bit smoother. I found both to be very good. But is there a difference in quality between the Antares and the Celestron or Meade focal reducers? Optically, it consists of a four-element lens that is fully multi-coated for high contrast and resolution. Please note, orders placed after 10am on 2/28/2023 will be delayed. If you place your camera at a different working distance, you will get a different reduction factor and perhaps unwanted distortion in the image. The Buyer's Guide To Eyepieces at the top of the Eyepieces forum has a column for this spec. I have this one Opticstar F6.3 Focal Reducer / Corrector. 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. 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. Despite never removing it no matter what I was looking at. Our proprietary StarBright XLT optical coatings dramatically increase transmission, up to 97.4% on our Schmidt corrector lenses. The working distance or required back focus, explained above, is usually specified and is far more important in practice. Download the Celestron PWI Telescope Control Software. 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. More important, its clear that the Antares is a reducer/corrector, just like the Celestron and not merely a reducer. I have had the Japan unit on the back of my C5 since 1994 or thereabouts. 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! Hmmm . and you will be fine. Or, when the distance of the focal reducer to the focal plane of the objective d1 equals the focal length of the focal reducer FR, the reduction factor MR = 0.5x. Many focal reducers for refractors have a working distance (or back focus distance) of 55mm. Now, Celestron is using that same technology to allow star gazers to connect to the night sky and enhance their experience of the cosmos in fun and unique ways. Field stop diameters are one of the specified specs of eyepieces. We have tested our current batch and it works with Meade, Celestron, and Baader SCT accessories. Most manufacturers provide this specification. In terms of reduction and correction - which are what reducer/correctors are supposed to do - both are superb. We do not price match competitors if they are out of stock. These 0.63x focal reducers were originally designed to optimize for an image circle to match 36mm x 24mm film or its digital equivalent for astrophotography. It seems right to put some distance between the camera and the focal reducer, right? Designed distancing using the reducer with a 1.25 visual back and 1.25 Televue mirror diagonal; 0.63x Starizona Focal Reducer for SCTs- Awesome Astrophotography The distance d2, which measures the position of the new focal plane of the objective from the back of the focal reducer is given by Equation 5: In these equations, d1, d2, and MR are all variables that depend on each other through Equations 2 and 4. This would tell us exactly how well aberrations are corrected. This factor is designated by a power that is less than 1, and it usually lies between 0.5x or 0.8x. And when d1 = FR, that is, when the focal reducer is placed at a distance from the focal plane of the objective that's equal to the reducer's focal length, the focal length of the combined optical system is Fo, so it acts as a 0.5x reducer. Reducer Lens .7x - EdgeHD 1100 - Celestron Photographically you also get a wider field and much shorter exposures. 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. Melotte 15 - First Process in PixInsight (easy! Your price: $579.00. With the barrel 1.25 reducer won't focus, all I get is fuzzy snowballs. We reserve the right to verify a competitor's advertised price and the availability of the item. You need to be a member in order to leave a comment. The female end attaches to the rear cell of the telescope. I wonder whether, for example, Antares focal reducer for SCT belongs to the latter category. Who cares? My experience is that CN sellers are way above those listing elsewhere. It was used strictly for imaging, not visual observing. 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. 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. The problem with those SCT reducers is that they cause chromatic aberration and require refocusing when using parfocal RGB/other filters. Request stock alerts and we'll let you know when the item is back in stock. This appendix summarizes how this works based on simple equations from the book Telescope Optics by Rutten and van Venrooij. Easy solution found a very tiny dab of super lube on the threads and all was well and quiet. 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. 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. Will not focus with the stuff I have. 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. This means that there must be sufficient travel on the telescope focuser to make up for this. 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. The visual back must be removed first. Article Agena AstroProducts, 2019. * Not a Retail Store * 16313 Arthur StreetCerritos, CA 90703, USA. You currently have javascript disabled. If you want to save a few buck watch the classifieds on CN. Clean, fun jokes the tradition continues - Page 106 Regardless, the difference was miniscule and is more than adequate on both and exceeds a 8 or 6 SCTs baffle tube diameter. Like you, I am primarily visually observing but I have everything together now that so I am going to start experimenting with photography so we'll see how it does there. Does anyone know if the Antares 4000 focal reducer is as good as the Celestron focal reducer. Wow, that is a very detailed discussion! 1.2" in that scope is a field stop of 43mm at f/10 and 27mm at f/6.3. Copyright 2003-2022 Agena AstroProducts. Once installed, you can add additional accessories like T-Adapters, 1.25 Visual Back, Star Diagonal, or Off-Axis Guider. The Reduction Factor and the Amount of Reduction are inversely related. Reducer Lens .7x - EdgeHD 925 Learn More. But I am rusty, can you condense a bit for me please? It works fine but you should stick with 1.25 EPs; or can use 2" EPs without corrector. I would not use the reducer with a 2" diagonal or eyepiece in the C6. This article explained the basics of how focal reducers work with various kinds of telescopes and how their working distance affects their reduction factor, and it provided sufficient detail to help amateur astronomer choose and use the right focal reducer for a particular application. This also resulted in the clear aperture of the Antares being about 39-39.5mm, versus the Celestrons 41mm. An eyepiece with a 27mm field stop yields a true field of 1.03 in the C6 at f/10. . control and Sky Viewer display makes selecting your target easy. 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. 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. A couple of tiny dust particles between lens elements, uneven lens edge blackening, very minor coating blemishes, or even a very small fine lens scratch or two are very common in this Antares product and must be accepted as normal for this item. The internal surfaces are blackened and glare-threaded to provide the highest contrast. 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. 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. Right off the bat, I was struck by how similar the two R/Cs were. 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. CPWI has an extensive object database, employs PointXP mount modeling, and more. If the reducer is placed elsewhere, at a position called the operating distance, the focal reduction factor will not be as advertised. Telescope Optics, Rutten and van Venrooij, Chapter 15, Willman-Bell (1988). It features a standard male SCT thread (2" OD, 24 TPI) on one side and a standard SCT female thread on the other. Overall, this reducer does a phenomenal job at preventing gradients due to internal reflections from the camera sensor back to the glass in the reducer, as I suffered with the Antares reducer. Sharpness is essentially the same. I don't know. Try & buy if you like - usual mates rates. My Celestron was made in China and the Antares in Canada. 2023 Celestron, LLC. In terms of reduction and correction which are what reducer/correctors are supposed to do both are superb. It must be in stock at the time of Price Match for us to make a guarantee. More about this below. Reducer Lens .7x - EdgeHD 1100. . This fully multi-coated lens provides maximum light transmission with near full-field illumination. Your eyepieces are the first accessories you should learn to use with your telescope. The Reducer/Corrector can also be used for terrestrial digiscoping. It is not a corrector or flattener. We only send interesting emails and will never sell your data. However, it will not thread into William Optics accessories, and with GSO it is a hit or miss. The amount of reduction is simply the percentage by which a reducer shortens the effective focal length of a telescope and is calculated as (1 Reduction Factor) x 100%. Focal reducers for these relatively fast ED refractors are generally for imaging only, not for visual observation. Never noticed any anomalies with this unit. This innovative software solves the time-consuming problem of trying to pinpoint the North Celestial Pole. Nada. For me, I was looking for, and planning to keep, the one that yielded the greatest reduction. Refractors, or SCTs with external focusers, may not have sufficient in-travel to reach focus in some configurations. Equation (4) shows the relationship between the distance d2 and the reduction factor MR. ED glass is specially formulated and contains rare-earth compounds that greatly reduce a visual defect called chromatic aberration. Focal reducers for refractors with focal ratio of f/7 to f/9, roughly, have a design reduction factor of about 0.75x to 0.8x and produce a flat field by correcting for the curvature of the objective lens. On the camera side, the focal reducer has male M42x0.75 or M48x0.75 threads that attach directly to the T-ring (with an M42-M48 adapter if necessary). Well done. I have Hirsch focal reducer, which is yet another clone of the Celestron reducer. No negative issues to report. For imaging, a T-adapter is threaded to the camera side of the focal reducer, which in turns connects to the camera with the appropriate hardware. Watch this before you buy Celestron 8SE SCT, or a Focal Reducer or a I think I remember hearing the reduction factor is slightly different, cant remember more or less reduction. We will be glad to help. Since then, Agena has become one of the leading online retailers of telescopes and astronomical accessories worldwide. I am new to these optic topics, and I want to ask you what happens with Masutov like SW or Celestron 4 or 7 inches. Maybe I got a lemon. Also read the reviews here, including those at 4 stars. Not a bit. Meade does not make an equivalent line of focal reducers for the ACF scopes, although some models of Meade ACF are already at f/8, faster than the f/10 ratio of Celestron Edge HD scopes. This filter threads on to the rear cell of your Celestron or Meade SCT telescope. 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. Thanks Peter! The nominal design reduction factor of these reducers is typically 0.5x. No results, please adjust your filters. 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. 3. This is one of our best-selling items, and customers have reported that this product is at least as good as, and probably better than, other leading f/6.3 focal reducers sold on the market for a lot more. control and Sky Viewer display makes selecting your target easy. Details: The item must be the identical item, brand name, size, weight, color, quantity and model number. Celestron Focus Motor for SCT, EdgeHD & 8" RASA, Celestron C6 0.63 reducer/flattener back focus. I have the Antares and have no complaints. With both, using the same diagonal set-up, the exact same stars were visible at the very edge of the FOV. Edited by Tony Bonanno, 16 April 2021 - 06:44 PM. This superb fully multi-coated multi-element focal reducer takes advantage of the latest computer aided design techniques to achieve the highest standards of performance set by the brand leaders at a fraction of the cost. 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. If you do so, you will achieve the design reduction factor. Fastar Technology allows imagers the option of drastically increasing the speed and sensitivity of their Celestron optical tube, allowing bright, detailed images with short exposures. Reducer - Corrector | Celestron For the best experience on our site, be sure to turn on Javascript in your browser. Start here to find the perfect telescope for you! Whereas the Celestron threaded smoothly onto the scope, the Antares chattered and squeaked a bit more so when being removed. The previous post shows the reducer on what appear to be two different refractors. 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. Back-Focus 101: DSLR Cameras & the Celestron f/6.3 Reducer - YouTube Generally, views through the Antares seemed a little more transparent and brighter. 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. However, doesn't fit in the telescope and even if it did wouldn't work. You can probably eke out 1.2 without noticing serious vignetting, which is a field stop of 31.5mm. Again, to my surprise, there was absolutely no difference between the Celestron and Antares on any star. I happily cycle through LRGB filters to build the image rather than do a whole run of one filter at a time. Unleash the full pointing accuracy of your Celestron computerized telescope with a specialized telescope control software suite. A f/10 focal ratio now achieves a f/6.3, while an f/11 focal ratio now achieves a f/7. Equation 6 & 7 item two & three does not make sense, both say increase its reduction (one should say reduce its reduction?). These RC reducers cannot be used with other types of telescopes. Please Log in to save it permanently. A longer effective focal length leads to higher magnification with a given eyepiece for visual observers. Reducer Lens .7x - EdgeHD 925 All Rights Reserved. Thank you so much for the informative article, I now understand better how to integrate my reducer into my system to get better performance. That said any comparison reviews are helpful. Blue Fireball M42 T/T2 Thread Camera Adapter for Prime Focus Photography - 2" # P-06, Celestron T-Ring for Canon EOS Camera # 93419, GSO 2" Crayford Focuser for SCTs - Dual Speed, Length of male SCT thread = 5mm (0.2") but this is preceded by an unthreaded part on the eyepiece side making the total length = 8.8mm (0.35"), Length of female SCT thread = 7.5mm (0.3"). A few people have reported issues with the male SCT thread diameter on this item being a bit larger than necessary. 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. My application is mostly visual now, but I'm looking to do more astrophotography over time. 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. All rights reserved. Fortunately, my neighbors are not out in their backyards at 11 pm, or they may have thought I was torturing a small mammal. 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. Upgrading the Focuser of Your Schmidt-Cassegrain Telescope - Agena Astro 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). riklaunim Members 559 3,445 Location: Poland Posted October 11, 2010 They are reported as identical. Again, swapping back and forth for a couple of hours on M44, M35, and several brighter stars, I examined the shape of specific stars near the edge of the field with both correctors. Can you help me? ), but stars seemed a bit tighter and their colors were richer and more dramatic. Copyright 2003-2022 Agena AstroProducts. Celestron is considered better in terms of QA, less likely to come with free dust, hair or fingerprint. With spring galaxy season here, I decided to pick up a couple more to compare in a head-to-head shoot out. 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. Obviously bright objects like Jupiter or The Moon show the reflections. 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 two samples I have PERFORM IDENTICALLY. However, I noticed immediately that the Antares had a bit more of an heft to it, giving it a solid feel the Celestron didnt possess. Focal Reducers - Complete Overview and Function - YouTube Antares f/6.3 SCT Focal Reducer - Rother Valley Optics Ltd Place the plastic covers on the lens when not in use to reduce the dust collection. You attach the focal reducer to the rear port on a SCT and can keep it covered. The reducer fits all Meade and Celestron . The focal length of a focal reducer is usually measured from the rear lens surface of the reducer (and not the reducer's housing). Weasner's Meade and Antares Focal Reducers Review Celestrons patented StarSense Technology makes it easier than ever to locate objects in the night sky, even if youve never used a telescope before. You may need spacers or a T-adapter to ensure the correcting working distance. Does anyone know if the Antares 4000 focal reducer is as good as the Celestron focal reducer. October 11, 2010 in Discussions - Scopes / Whole setups. Your wishlist has been temporarily saved. Michael 1 ronin Members Newtonian reflectors will seldom be able to accommodate the in-focus travel demanded by focal reducers. In your opinion, is the Celestron is worth the added cost ($150 vs. $90)? What an enjoyable read and detailed comparison. 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. 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. OPT Product Number: AE-SCTFR specifications Warranty 2 Year Warranty Works as advertised! The review is a subjective visual impression, which is interesting but not best evidence. Contiguous US Customers:All items we sell ship for free within the Contiguous US. InternetSales@optcorp.com. This should not be the case if they have their purportedly different focal lengths. 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. During check-out, you will be presented with several shipping choices and costs. 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. Just one question. As another example,GSO makes focal reducers for their line of Ritchey-Chretien imaging telescopes. 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. The reducer is we might presume designed to correct to some as yet un-measured extent, the image of a standard SCT. At least these two units I tested make the answer - whatever. For the best experience on our site, be sure to turn on Javascript in your browser. Performance wise what differences might there be using the reducer on a smaller scope. 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? 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. In many cases, the answer is yes, especially for electronically-assisted astronomy (EAA). Unlike SCT telescopes, Ritchey-Chretien telescopes and Celestron Edge HD or Meade ACF scopes have internal optics that provide an inherently flat field, so these telescopes require a special focal reducer than does not provide additional correction for field curvature. An image of about 24mm across, approximately, allows an observer to use a 1.25" eyepiece with a maximal field stop. Just point the telescope at any three bright objectsstars, bright planets, or even the Moonand your telescope can orient itself with the night sky. Focal reducers also move the effective focal plane of the objective inward, that is, towards the objective (see Figure 1). The new Lithium Phosphate (LiFePO4) battery chemistry has significant advantages over other battery chemistries, great for for those Astronomers on the go. But in the end they both do pretty much the same thing and it sounds like any performance difference is subtle. 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.