Sign up for a new account in our community. The click-lock with a 2 dielectric diagonal with a somewhat shorter light path, using both a 2 ES 28mm/68 and the same low-profile adapter with a 1.25 ES 24mm/68. Edited by bluewater, 05 September 2020 - 11:27 AM. Start Chat 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. Article Agena AstroProducts, 2019. Manish holds a Master's degree in Electrical Engineering from Virginia Tech and an MBA from the Kellogg School of Management at Northwestern University. A little longer light path with a 2 Baader click-lock, low profile 1.25 adapter, and the 1.25 diagonal; The telescope side of the barrel is often threaded with an M48 x 0.75 thread for standard 2" astronomy filters. More important, its clear that the Antares is a reducer/corrector, just like the Celestron and not merely a reducer. InternetSales@optcorp.com. This "speeds up" the optical train by reducing the focal length and magnification of the scope, requiring less time to integrate the same signal. 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. Start here to find the perfect telescope for you! The lens is housed in machined aluminum for are machined aluminum black anodized. The C8 has no noticeable vignetting with a 32mm Plssl in the f/6.3 reducer. How about for visual observers? No results, please adjust your filters. 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. Since 2008, Brian has taught astronomy to tens of thousands of stargazers through his websites OneMinuteAstronomer.com and CosmicPursuits.com. 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. OPT Product Number: AE-SCTFR specifications Warranty 2 Year Warranty Works as advertised! We do not price match competitors if they are out of stock. The previous post shows the reducer on what appear to be two different refractors. 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. Never noticed any anomalies with this unit. Hi. The reduction factor MR can also be written in terms of d2 as: When the focal reducer is placed at the working distance, D, that is when d2=D, then the reduction factor MR is equal to the design reduction factor MRD: Equations (6) and (7) imply these important considerations: Most manufacturers do not publish the focal length of their focal reducers, so it is not usually possible to calculate the working distance and design reduction factor. But the smaller image circle means there is a limit to the field stop of an eyepiece that can achieve an unvignetted image. At least these two units I tested make the answer - whatever. October 11, 2010 in Discussions - Scopes / Whole setups. 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. Never used one, but read the reviews here that suggest a coating problem. 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. 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. 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. Nowadays I tend to use the Celestron more with my refractors for imaging and viewing. 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. if the illuminated field is 27mm wide without the reducer, it will be 27 x 0.63 = 17mm with it in place. The Reduction Factor and the Amount of Reduction are inversely related. Nada. You cannot, for example, use a 0.63x focal reducer intended for a standard Celestron or Meade SCT and use it on a Celestron Edge HD or a Meade ACF. By using this site, you agree to our Terms of Use. Focal reducers also move the effective focal plane of the objective inward, that is, towards the objective (see Figure 1). Despite never removing it no matter what I was looking at. Still not sure what is the right gear for you? I've looked through one from Meade and first impression was that it was like the Celestron version. They usually have a 2" barrel that slides into the telescope focuser. This fully multi-coated lens provides maximum light transmission with near full-field illumination. But is there a difference in quality between the Antares and the Celestron or Meade focal reducers? It features a standard male SCT thread (2" OD, 24 TPI) on one side and a standard SCT female thread on the other. This should not be the case if they have their purportedly different focal lengths. All Rights Reserved. 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. Reducer Lens .7x - EdgeHD 800 Learn More. 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. Can these economical focal reducers from GSO and other vendors result in good images? I use the same back spacing for both on a small 6" Celestron SCT. In terms of reduction and correction which are what reducer/correctors are supposed to do both are superb. It's easy! I found both to be very good. 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. 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. Equation 6 & 7 item two & three does not make sense, both say increase its reduction (one should say reduce its reduction?). The reducer features fully coated optics in an anodized aluminum filter ring with an ergonomic rubber grip. Just point the telescope at any three bright objectsstars, bright planets, or even the Moonand your telescope can orient itself with the night sky. Another factor to consider: focal reducers also increase the angle at which light approaches the focal plane. Since the focal length of the reducer, FR, is fixed, as d2 increases then MR decreases. A useful thing to know is how far from the objective lens (for a refractor) is the focal reducer located. For imagers using longer focal-length refractors and SCTs, especially when using smaller sensors that place less demand on the focal reducer, there are economical alternatives for focal reducers from manufacturers such as GSO, Agena, and Antares. We process your personal data as stated in our. This focal reducer is made to attach to the rear cell of Schmidt-Cassegrain or Maksutov-Cassegrain telescopes. Not one detectable iota of discernable difference. Reducer - Corrector Learn More. I've seen some older threads saying that the Celestron, Meade and Antares FRs are all the same and manufactured in the same factory. No negative issues to report. Once installed, you can add additional accessories like T-Adapters, 1.25 Visual Back, Star Diagonal, or Off-Axis Guider. In many cases, the answer is yes, especially for electronically-assisted astronomy (EAA). If used before or beyond the working distance, unwanted image distortion may result. Take control of your telescope! No retailers currently carry this product. Now It only focuses near things, like some kind of macro zoom. 160K views 9 years ago This video is a complete overview of focal reducers and how they function applying to telescopes. Style: Celestron makes a series of focal reducers for the Edge HD line that are matched to the 8", 9.25", 11", and 14" apertures of these scopes. 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. riklaunim Members 559 3,445 Location: Poland Posted October 11, 2010 They are reported as identical. 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. 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. ED stands for "extra-low dispersion," which refers to the composition and optical properties of the glass used for the lenses. If the reducer is placed elsewhere, at a position called the operating distance, the focal reduction factor will not be as advertised. In the 1960s, Celestrons founder, Tom Johnson, created groundbreaking new telescopes never before seen on the consumer market. 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. Focal reducers for refractors are easy to use. 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. Powered by Invision Community. 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. 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 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. I doubt there is any difference between the Antares and the Celestron except price. More about this below. 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. Field stop diameters are one of the specified specs of eyepieces. Download the Celestron PWI Telescope Control Software. An eyepiece with a 27mm field stop yields a true field of 1.03 in the C6 at f/10. 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. 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. I have Hirsch focal reducer, which is yet another clone of the Celestron reducer. However, some focal reducers can be used over a wider range of working distances, especially those with simpler optical design, and especially when used with cameras with smaller sensors. 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. JavaScript seems to be disabled in your browser. 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. looks virtually identical, except for the lettering. Community Forum Software by IP.BoardLicensed to: Cloudy Nights, E of San Francisco Bay and W of the Awahnee, This is not recommended for shared computers, reviews here that suggest a coating problem, Back to Celestron Computerized Telescopes, Looking for advice on first refractor and camera. 2. 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. Some faster refractors with a focal ratio of f/6, for example, only require field flatteners and not focal reducers. 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). But in the end they both do pretty much the same thing and it sounds like any performance difference is subtle. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.International Customers:Free shipping does not apply to international orders. It's highly unlikely that they could be so precisely identical unless they were. Get ready for a night of astroimaging with your mount faster than previously thought possible with All-Star Polar Alignment. The focal length and design working distance for this focal reducer were not available from the manufacturer. 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. A few people have reported issues with the male SCT thread diameter on this item being a bit larger than necessary. However, in principle, the reduction factor of a focal reducer can be varied by changing the distance from the back of the focal reducer to the camera or eyepiece. He also holds a Ph.D. in engineering physics from McMaster University. Brian Ventrudo is a writer, scientist, and astronomy educator. So Celestron buyers like Celestron, Meade buyers like the Meade and Antares buyer like the Antares. 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.