In practice, it's important to remember that you will rarely operate at the exact working distance and at the exact reduction factor that is specified. How does it look thats what matters. It must be in stock at the time of Price Match for us to make a guarantee. However, with appropriate spacers and a camera with a known back-focus, it is easy to determine the exact amount of focal reduction for a given setup (some imaging software packages will also let you derive this from images). The most popular accessories for your new telescope! 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. Thanks guys, I'm trying to get my ZWO ASI120MC-S to work with my 90mm Meade. Not noticed any optical problems. 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to the design reduction factor MRD: Equations (6) and (7) imply these important considerations: Most manufacturers do not publish the focal length of their focal reducers, so it is not usually possible to calculate the working distance and design reduction factor.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 I am rusty, can you condense a bit for me please? It was used strictly for imaging, not visual observing. More important, its clear that the Antares is a reducer/corrector, just like the Celestron and not merely a reducer. I've only used it a few times but it looks good to me. Since the Celestron and Antares are supposed to have different focal lengths and spacing specs, I expected different results. Best evidence would by obtained by using a camera and evaluating the image both by eye and with a computer analysis. In every configuration, there were essentially parfocal, requiring only a tiny fine focus adjustment when changing correctors. 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. 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. All rights reserved. How about for visual observers? You currently have javascript disabled. This filter threads on to the rear cell of your Celestron or Meade SCT telescope. 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). But the smaller image circle means there is a limit to the field stop of an eyepiece that can achieve an unvignetted image. 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! 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. A former wireless communications consulting engineer and management consultant to various Fortune 500 companies, Manish started Agena AstroProducts in 2003. Steve 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. Is there likely to be any differences in performance between using these on an 8 or something smaller like my 6SE? No small animals were harmed in making these observations. 2023 Celestron, LLC. My application is mostly visual now, but I'm looking to do more astrophotography over time. 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). Since 2008, Brian has taught astronomy to tens of thousands of stargazers through his websites OneMinuteAstronomer.com and CosmicPursuits.com. Bear in mind you can't squeeze blood out of a turnip, i.e. 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. Assuming you use the reducer with the stock 1.25" diagonal, it will operate at f/6.3. During a twenty-year scientific career, he developed laser systems to detect molecules found in interstellar space and planetary atmospheres, and leveraged his expertise to create laser technology for optical communications networks. Free shipping $189.95 This article explains the basics of how focal reducers work with an astronomy telescope. These reducers can also be used for visual observing with SCT scopes with eyepieces with a field stop as large as 24-27mm. We only send interesting emails and will never sell your data. If used before or beyond the working distance, unwanted image distortion may result, especially when using cameras with larger sensors. 800-483-6287 I use it on my C8 SCT with a 1000d, and it seems to do everything written on the tin. Check out our 2022 telescope buying guide here! CEL-94245. CPWI has an extensive object database, employs PointXP mount modeling, and more. So, this past week I challenged the Antares and Celestron models to a head-to-hear on my C8 on some decent nights of good seeing and transparency in my Bortle 5-6 urban skies. Reducer - Corrector This fully multi-coated lens provides maximum light transmission with near full-field illumination. 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? This is very impressive performance given how hard this problem is to mitigate in general. The stars at the edge could be worse or better. Read our guide! Style: Each focal reducer has a fixed specification called the working distance or required back focus. 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. It also leads to larger (although fainter) images of extended objects like the Moon or planets for astrophotographers or visual observers. The equations in the Appendix show how this all works. As one increases, the other decreases. 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. control and Sky Viewer display makes selecting your target easy. Celestron Solar Safe filter technology is GUARANTEED SAFE for direct solar observation and has been independently tested by SAI Global Assurance Services. Because I have not heard any complaints about the made in China R/C. Contiguous US Customers:All items we sell ship for free within the Contiguous US. ), but stars seemed a bit tighter and their colors were richer and more dramatic. Reducer Lens .7x - EdgeHD 800 Learn More. There is a way to make subjective data more useful and that way is proper blind, or better still. With the barrel 1.25 reducer won't focus, all I get is fuzzy snowballs. Orders placed after 12:00 PM Pacific Time will be shipped the next business day. Celestrons award-winning Nature DX binocular gets a major upgrade with the addition of ED objective lenses. If I had to guess, the difference is maybe 10-15 grams. A focal reducer does just the opposite of a Barlow lens or focal extender. For the best experience on our site, be sure to turn on Javascript in your browser. a Tele Vue Panoptic), or a Plossl eyepiece with an apparent field of view of 50 and a focal length of 32mm. There is one difference though the Antares came with only one lens cap whereas the Celestron had a cap for both ends. Manish holds a Master's degree in Electrical Engineering from Virginia Tech and an MBA from the Kellogg School of Management at Northwestern University. Focal reducers for these relatively fast ED refractors are generally for imaging only, not for visual observation. The threads were similar on the eyepiece end, but a bit smoother. Celestron or Antares? I've looked through one from Meade and first impression was that it was like the Celestron version. There will be no shipments on 3/1/2023, 3/2/2023, or 3/3/2023 (March 1st - March 3rd, 2023). Yet, the Antares still easily and fully threaded without any hitches. I read another thread in a different forum about F6.3 reducer correctors and one amateur posted an image about glue coming out of an astromania f6.3 reducer which he planned to return. You can probably eke out 1.2 without noticing serious vignetting, which is a field stop of 31.5mm. 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. If the reducer is placed elsewhere, at a position called the operating distance, the focal reduction factor will not be as advertised. 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). This would tell us exactly how well aberrations are corrected. My Celestron was made in China and the Antares in Canada. 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. The review is a subjective visual impression, which is interesting but not best evidence. Even though they may have been slightly dimmer, galaxies were a bit easier to tease out of the urban light soup I deal with. 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. They are commonly available in 1.25" and 2" threaded cells that conveniently thread into the nosepiece of a compatible camera or the barrel of an eyepiece. We reserve the right to verify a competitor's advertised price and the availability of the item. Your eyepieces are the first accessories you should learn to use with your telescope. In these equations: The combined focal length of the objective and focal reducer is given by Equation 1: For example, when d1=0, that is, the focal reducer is at the focal plane of the objective, Fcomb=Fo, so the focal reducer has no effect.