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Celestron – Focal Reducer & Field Corrector Imaging Accessory – Reduces Focal Length & Ratio 37% – f/10 to f/6.3 – Ideal for Deep-Sky Observing & Astroimaging – Works w/Schmidt-Cassegrain Telescopes

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$160.55

$ 66 .99 $66.99

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1.Style:Corrector


About this item

  • LIKE HAVING TWO TELESCOPES IN ONE: Your long focal length Schmidt-Cassegrain is well suited to lunar and planetary work. Add the Reducer Corrector and you have a short focal length telescope perfect for deep sky observing and astrophotography.
  • REDUCES FOCAL LENGTH AND F/RATIO BY 37%: Simply thread the reducer onto your telescopes rear cell and an f/10 Schmidt-Cassegrain becomes f/6.3. An f/11 instrument becomes f/7.
  • COMPATIBLE WITH ALL YOUR ACCESSORIES: Once the reducer is installed, you can add accessories like a T-Adapter, visual back, star diagonal or off-axis guider as usual.
  • GREAT FOR TERRESTRIAL DIGISCOPING: The faster f/ratio allows you to shoot in dimmer lighting conditions and still properly expose your subject. This fully multi-coated lens provides maximum light transmission with near full-field illumination.
  • UNBEATABLE WARRANTY & SUPPORT: Buy with confidence from Celestron, a leading telescope brand in California since 1960. Your purchase includes a 2-Year US Warranty and unlimited support from our team of US-based experts.


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. With the Celestron Reducer/Corrector Lens, that’s precisely what you get. Explicitly designed for Celestron Schmidt-Cassegrain telescopes, this unique lens reduces your telescope’s focal length and f/ ratio by 37%, turning your long focal length telescope into a fast, short focal length instrument. A f/10 focal ratio now achieves a f/6.3, while an f/11 focal ratio now achieves a f/7. For visual use, this means you get lower power with the same eyepiece and a wider field of view. Photographically you also get a wider field and much shorter exposures. 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). Once installed, you can add additional accessories like T-Adapters, 1.25” Visual Back, Star Diagonal, or Off-Axis Guider. The Reducer/Corrector can also be used for terrestrial digiscoping. The faster f/ratio allows you to use slower film or shoot in lower light level situations and still properly expose your subject. This fully multi-coated lens provides maximum light transmission with near full-field illumination. The lens is housed in machined aluminum for are machined aluminum black anodized. The internal surfaces are blackened and glare-threaded to provide the highest contrast. The lens has a knurled surface, providing a tremendous gripping surface for threading/unthreading.


Ryan Bowhall
2025-09-03 11:44:08
Excellent enhancement to planetary viewing.
Jahan Dawlaty
2025-08-12 21:03:49
I put this on my celestron 8se SC telescope with the goal of increasing the field of view (because I have a zwo asi224mc camera with a relatively small sensor area). It was easy to install and worked quite well. Before buying it, I was worried that the focal plane would shift so much that I would not be able to focus within the limits of my focusing knob. But that worry was unfounded and I got to focus easily. I could fit the Dumbbell nebula with enough contextual background in the field of view of my camera. As far as I could tell, I did not observe significant vignetting. My plan is to leave it in the back of the telescope forever and only take it off when doing planetary observation or imaging (which requires higher magnification).
Zauber
2025-08-04 10:55:02
Mejora significativamente un Nexstar reduciendo su larga focal, haciéndolo más rápido en la captación de luz. Me gustó la calidad de su óptica. Me ha permitido mejorar las tomas y observación de objetos celestes de cielo profundo. La foto de la Nebulosa de Tarántula no es de gran calidad pero no es culpa del reductor focal. Ya sido una toma una toma con cámara planetaria. Aún lo estoy probando
J. Sands
2025-07-26 15:13:22
This focal reducer turns my slow f/10 Celestron C-8 into a much faster f/6.3 telescope! It brightens and flattens the field significantly rendering stars sharp in the corners of my micro four thirds images. Highly recommended!
Railbird
2025-07-07 13:20:40
My main motivation for buying this was to fit the sun (and moon) into the field of view of my APS-C (24 x 16 mm) camera sensor using my Celestron 8" SCT (2000 mm FL). Using a full frame sensor is not an option since the C8 will vignette. This device also allows a slightly wider field of view and lower f-number for deep space object astrophotography.Handy reference numbers for those wishing to photograph the Eclipse or just the entire moon: Max focal length when using an APS-C camera is about 1260 mm. When using a full frame, about 1900. But only if you can center the target and keep it centered. (To photograph the moment of eclipse use 400mm APS-C/600mm Full Frame and no solar filter.)This device is not useful for solar system astronomy, except the sun or moon, or when using eyepiece projection photography. But you can always just take it off.One huge advantage of this device is that you get just about the same performance as you would with an Edge HD telescope, and the field flattener costs half as much. If you buy an Edge HD 8" OTA you get a built-in field flattener, but still have the longer focal length, and hence smaller field of view and slower f-number. To see the whole sun or moon, or a more of the Pleiades in a camera, you would have to buy another focal length reducer, about $300 bucks. Since the Edge HD comes at a $400 buck premium over the SCT you spend an additional $700 bucks to get to the same optical setup you get with the the SCT plus this item at about $150 bucks. Go with this plus the SCT and save $550 bucks, and you will even have less glass between you and the stars to boot.The construction is very solid, you should have no problem hanging a DSLR (or better a mirrorless camera) off of this thing.
OSVALDO
2025-07-06 14:56:03
cumple con lo ofrecido
Ronald Hicks
2025-05-22 12:38:06
works real lwell with my c-8
Night Sky Fan
2025-04-14 11:04:29
I am sorry that I did not buy this accessory two years ago. It all began with a used Celestron C5. Then I bought a very nice used Nexstar 8SE and thought wow, I should have done this go-to thing sooner. After a year or so, I moved up to a new Celestron CPC925 and decided to explore video astronomy with an inexpensive Samsung SBC-2000 security cam. Most SCTs have a focal ratio of about f/10 (focal length divided by aperture) but a camera works better with a faster (shorter focal length) scope. The usual way to do that with a video camera is to screw on a small .5x reducer. So I bought on of those for $35 and was just amazed at the detail and colors in the Dumbbell Nebula. Then someone over at Cloudynights.com suggested that try adding a f/6.3 reducer (stacking reducers). So I bought the f/6.3, screwed in on the back of the CPC925, replaced the visual back and diagonal, mounted the camera (without the .5x) and stayed up until 2AM looking at the Orion Nebula. Before heading for bed, I pulled the camera, put in a 20MM 68 degree APOV eyepiece, and had another "Wow!" moment.The Celestron f/6.3 reducer-corrector really brightens the image, widens the field of view, improves contrast and detail, and flattens the image improving the look of stars near the edge of the field of view. Many people leave them on all of the time except when looking at the moon and planets or other high magnification situation.There are other and cheaper reducers on the market and they do work. However not all of them offer the same degree of improvement at the edge of the field of view. Rod Mollise writes "...6.3 r/cs are one of the best--if not the best--SCT accessories to ever come down the pike" and "I'll put it this way...the 6.3 rarely comes off the rear cell of the C8."
Ron Osborne
2025-04-09 20:27:58
Bought this as return with unspecified minor flaws. Turned out to be just some crap on the lens that easily wiped off. If you own a Celestron C8 and want to see the entire moon its a must-have.
Felisberto Andreas Bub
2025-04-08 15:08:47
Ainda não tive a oportunidade para utilizar. Mas o produto parece ser de boa qualidade, bem construído, em alumínio fundido e pintado, lente multi-coated.
JG
2025-03-11 14:48:20
Muy buena calidad de imagen y materiales.
R. Paris
2025-01-22 12:58:30
Bought for my Celestron C5.Works well, nicely machined, solid and let's you have two telescopes for the price of one!
Mr. G. Marchant
2024-12-18 10:47:40
This seems to work well on my 1970s celestron classic orange tube c8. From what I have seen weather permitting it’s seems to work well. But the weather in the uk has been mixed back over the months and not had a good long time to test the item. But in a short test it’s working well.
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