These reducers have a back focus (or design working distance) of 80mm. I have an 8SE, and am thinking about getting a focal reducer. 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. OPT Product Number: AE-SCTFR specifications Warranty 2 Year Warranty Works as advertised! An eyepiece with a 27mm field stop yields a true field of 1.03 in the C6 at f/10. Go behind the scenes with Celestrons product development team and learn more about our award-winning and patented innovations. More aggressive reduction, or using these reducers with larger sensors, will result in aberrations and distortions near the edge of the image. In every configuration, there were essentially parfocal, requiring only a tiny fine focus adjustment when changing correctors. Perfect for the serious student, professional scientist and discriminating hobbyist. 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. You don't need to follow these equations to use a focal reducer, but they do show how the reduction factor changes with the placement of the reducer. As a Barlow's magnification increases with increasing distance from the Barlow, a focal reducer's reduction increases with increasing distance from the reducer. Unleash the full pointing accuracy of your Celestron computerized telescope with a specialized telescope control software suite. A useful thing to know is how far from the objective lens (for a refractor) is the focal reducer located. Focal Reducers - Complete Overview and Function - YouTube No retailers currently carry this product. Many focal reducers are meant to be used within a few millimeters of the specified working distance to achieve the best possible image results. 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. A few people have reported issues with the male SCT thread diameter on this item being a bit larger than necessary. 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. You attach the focal reducer to the rear port on a SCT and can keep it covered. Figure 1 shows the relationship between the focal reduction factor MR and the position of the reducer in the optical path. At least these two units I tested make the answer - whatever. It must be in stock at the time of Price Match for us to make a guarantee. Sign up to receive sale alerts, news about upcoming celestial events, and telescope tips from our experts! One of the most important factors in a telescope is its transmissionthe percentage of light that reaches the focal plane. Once focused it's pretty good. a Tele Vue Panoptic), or a Plossl eyepiece with an apparent field of view of 50 and a focal length of 32mm. Explore Scientific Keys to the Universe Sale. Product Details. 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. In terms of reduction and correction which are what reducer/correctors are supposed to do both are superb. Watch this before you buy Celestron 8SE SCT, or a Focal Reducer or a Reducer Lens .7x - EdgeHD 800 Learn More. My Celestron was made in China and the Antares in Canada. Quite interestingly it bears the very same engravings of the Meade 4000 r/c (including "series 4000") except for "MEADE". Some manufacturers will specify the working distance from the middle of the rear lens surface, and this number must then be converted into a practical working distance number by subtracting the amount by which the rear lens surface is recessed in its housing. 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. This filter threads on to the rear cell of your Celestron or Meade SCT telescope. This would tell us exactly how well aberrations are corrected. Is there likely to be any differences in performance between using these on an 8 or something smaller like my 6SE? That was fun. 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. 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. USD $80.00. 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. Because most modern Newtonians already have relatively fast focal ratios, these telescopes do not usually use focal reducers. Not one detectable iota of discernable difference. 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. Reducer Lens .7x - EdgeHD 1400 I'm going with the Celestron. Reducer Lens .7x - EdgeHD 800 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. Observing the microscopic world has never been easier! control and Sky Viewer display makes selecting your target easy. Is that distance D= Fo-d1=Fo-(d2/MR)? They are also less expensive than many external focusers of similar build quality. 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). 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. Please let us know what topics you are interested in. This focal reducer is made to attach to the rear cell of Schmidt-Cassegrain or Maksutov-Cassegrain telescopes. 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. It's usually specified in millimeters. I had a Celestron, Antares and Hirsch for awhile and compared them over about a year. 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. Who cares? There may have been an almost imperceptible difference, but the Antares and Celestron were producing precisely the same reduction. 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. 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. Optically, it consists of a four-element lens that is fully multi-coated for high contrast and resolution. First, let's have a look at some key optical parameters are needed to understand focal reducers. F 6.3 focal reducer/corrector. - Discussions - Stargazers Lounge It covers the basic optics and design specifications of a focal reducer, and goes through some practical factors to consider when selecting and using a focal reducer. The stock Celestron visualback is just under 2 long. It is not a corrector or flattener. Both exhibited consistent reduction, identical field flattening, and edge correction properties, and both were high quality optically and mechanically. Hello! Rather than a direct side-by-side, I swapped the reducers so that I was using them on the exact same, well-collimated instrument. Now It only focuses near things, like some kind of macro zoom. Powered by Invision Community. More important, its clear that the Antares is a reducer/corrector, just like the Celestron and not merely a reducer. The reducer features fully coated optics in an anodized aluminum filter ring with an ergonomic rubber grip. In the 1960s, Celestrons founder, Tom Johnson, created groundbreaking new telescopes never before seen on the consumer market. Figure 2 shows the effective of a focal reducer on the light from a telescope objective. Some faster refractors with a focal ratio of f/6, for example, only require field flatteners and not focal reducers. As a consequence, the standard f/6.3 and f/3.3 focal reducers for SCT scopes do not work. Another factor to consider: focal reducers also increase the angle at which light approaches the focal plane. This is the simplest way to attach your ASI121 to your telescope. Telescope Focal Reducers & Correctors - High Point Scientific 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. Stars had a tiny bit more sparkle and pop. More about this below. Many focal reducers for refractors have a working distance (or back focus distance) of 55mm. 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). Like many of us with SCTs, I have bought and sold a number of f/6.3 reducer/correctors over the years, and I have always been curious how they really stack up to each other. Right off the bat, I was struck by how similar the two R/Cs were. It is recommended for . Never noticed any anomalies with this unit. None of this was offensive, nor did it interfere with views in any significant way. The working distance or required back focus, explained above, is usually specified and is far more important in practice. 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. One focal reducer will not achieve optimum results with all types of telescopes, so there is no universal' focal reducer. Thanks Peter! How to Set the Correct Back Focus for Your Telescope (Guide) More details are found in the Appendix of this article. Obviously bright objects like Jupiter or The Moon show the reflections. These reducers can also be used for visual observing with SCT scopes with eyepieces with a field stop as large as 24-27mm. 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) Share Customers Also Purchased Description Reproduction without permission prohibited. The Antares focal reducer comes in small box. 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. So it provides a 0.63x design reduction factor when used with an f/10 SCT at the specified working distance. Weasner's Meade and Antares Focal Reducers Review Generally, views through the Antares seemed a little more transparent and brighter. if the illuminated field is 27mm wide without the reducer, it will be 27 x 0.63 = 17mm with it in place. 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. Therefore, a 55mm back focus with a filter that is 3mm thick added to the imaging train would become 56mm. The reducer is we might presume designed to correct to some as yet un-measured extent, the image of a standard SCT. Download the Celestron PWI Telescope Control Software. It's easy! 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. No difference. Housings, threads, reduction, correction, blah, blah, blah. 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). Not a bit. 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. In some cases, focal reducers also act as field flatteners by correcting for field curvature and coma of the objective lens. No rainchecks will be issued for items out of stock at OPTcorp.com to match a competitor's price. If I had to go out on a very thick limb, I would have to say that these two reducers/correctors are, indeed, identical the exact same glass in slightly different housings with different lettering. Celestron Solar Safe filter technology is GUARANTEED SAFE for direct solar observation and has been independently tested by SAI Global Assurance Services. 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.
Les Paul Bolt On Neck Replacement,
Flip Or Flop North Hollywood House Sold,
Mira Kapoor Age When She Got Married,
Articles A
