Nebula Filters. Your eyepieces are the first accessories you should learn to use with your telescope. Celestrons FREE planetarium app is an astronomy suite that redefines how you experience the night sky. Whereas the Celestron threaded smoothly onto the scope, the Antares chattered and squeaked a bit more so when being removed. That is definitely a 2" eyepiece, but it is not a large or long focal length 2" eyepiece. Product Details. Please let us know what topics you are interested in. The Best Dedicated Astronomy Cameras for Beginners, Astronomik OIII 12nm CCD Filter - T-Threads, Pegasus Astro Dual Motor Focus Controller, 10 Micron 12kg (26.45lbs) Stainless Steel Counterweight- GM 2000, I would like more information regarding stock availability dates. The threads were similar on the eyepiece end, but a bit smoother. 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. If the reducer is placed closer to the eyepiece or camera than the distance D, the reduction factor decreases. Can these economical focal reducers from GSO and other vendors result in good images? If you do so, you will achieve the design reduction factor. That said any comparison reviews are helpful. 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. I found both to be very good. By There are many different types of focal reducers and they all effect. We have corrected # (iii) after equations 6 & 7. The reducer is we might presume designed to correct to some as yet un-measured extent, the image of a standard SCT. This may be a problem if the focuser tube or the diagonal (for visual observing) is too narrow to accept light at this larger angle. 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. 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. No negative issues to report. Meade once made an f/3.3 focal reducer for SCT scopes. Also read the reviews here, including those at 4 stars. The most significant mechanical variation, however, is the quality and precision of the threading. The review is a subjective visual impression, which is interesting but not best evidence. The lens has a knurled surface, providing a tremendous gripping surface for threading/unthreading. However, it will not thread into William Optics accessories, and with GSO it is a hit or miss. This factor is designated by a power that is less than 1, and it usually lies between 0.5x or 0.8x. which looks like the same one. This focal reducer and field flattener consists of a four-element multicoated 40mm lens in a metal cell. It's usually specified from the base of the mounting threads on the reducer's housing, and this is the most practical way of providing this specification. Thanks Peter! 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. So Celestron buyers like Celestron, Meade buyers like the Meade and Antares buyer like the Antares. Since the Celestron and Antares are supposed to have different focal lengths and spacing specs, I expected different results. riklaunim Members 559 3,445 Location: Poland Posted October 11, 2010 They are reported as identical. The price for an item/offer must be listed and valid at the time of match. Copyright 2021 Stargazers Lounge 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. This filter threads on to the rear cell of your Celestron or Meade SCT telescope. 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. Michael 1 ronin Members 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. Equation 6 & 7 item two & three does not make sense, both say increase its reduction (one should say reduce its reduction?). This fully multi-coated lens provides maximum light transmission with near full-field illumination. 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. The reducer fits all Meade and Celestron . It must be in stock at the time of Price Match for us to make a guarantee. It's highly unlikely that they could be so precisely identical unless they were. 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. 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. External Focusers for Schmidt-Cassegrain Telescopes 3.1 The Basics of SCT Threads 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. Not a bit. This Antares 1.25" 0.5x focal reducer lens (tele-compressor) is used under the Orion brand name to thread into the nosepiece of Orion StarShoot Solar System cameras and StarShoot Deep Space Color Imaging Camera. I've seen some older threads saying that the Celestron, Meade and Antares FRs are all the same and manufactured in the same factory. Focal reducers for these relatively fast ED refractors are generally for imaging only, not for visual observation. You need to be a member in order to leave a comment. But I am rusty, can you condense a bit for me please? Focal reducers also move the effective focal plane of the objective inward, that is, towards the objective (see Figure 1). 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. 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. Focal reducers are essential optical accessories for astrophotography, electronically-assisted astronomy (EAA), and in some cases, for visual observation with long focal ratio telescopes. 2023 OPT Telescopes. 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. 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. This appendix summarizes how this works based on simple equations from the book Telescope Optics by Rutten and van Venrooij. Thanks for pointing this out. Orders placed over the weekend will be shipped on the following Monday. 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. Well done. I even lost track of which reducer I was using. 2. Given past experience with them, I decided not to include the Meade version in my little experiment, as I have never met one I liked from getting one of the too-short focal length models, to one with some overflow cement in the doublet, to focus difficulties with some eyepieces. Not one detectable iota of discernable difference. Increase that distance, and greater reduction results and visa versa. There may have been an almost imperceptible difference, but the Antares and Celestron were producing precisely the same reduction. 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). Thanks. Manish holds a Master's degree in Electrical Engineering from Virginia Tech and an MBA from the Kellogg School of Management at Northwestern University. 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. Reducer Lens .7x - EdgeHD 1400 Learn More. The f/6.3 reducer is operating at f/5-f/5.5 with a 2" diagonal, depending on the back focus length of the diagonal. By using this site, you agree to our Terms of Use. Many Ritchey-Chretien telescopes available today are made by GSO. The Celestron f/6.3 is ~150 compared to the Antares at ~70. Your mileage may vary. This "speeds up" the optical train by reducing the focal length and magnification of the scope, requiring less time to integrate the same signal. Reviews. But in the end they both do pretty much the same thing and it sounds like any performance difference is subtle. Perfect for the serious student, professional scientist and discriminating hobbyist. However, the China 6.3 R/C has noticeable internal reflections that I haven't figured out yet. I think I remember hearing the reduction factor is slightly different, cant remember more or less reduction. I have the Antares and have no complaints. 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. 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. I use it on my C8 SCT with a 1000d, and it seems to do everything written on the tin. In most cases, the easiest option is to choose the focal reducer made specifically for your telescope. Most manufacturers provide this specification. In this case, an additional T-adapter (with an optical length of 50mm) is needed to get the spacing correct for a DSLR or other camera with a 55mm back focus. Great report and verifies what I had thought all along, Fortunately, my neighbors are not out in their backyards at 11 pm, or they may have thought I was torturing a small mammal.
What To Do If Stopped By Mexican Police,
Kirk Cousins Stats By Quarter,
Monarch Carolina Reaper Wing Sauce Scoville,
Articles A
