Antares F/6.3 SCT Focal Reducer

Antares F/6.3 SCT Focal Reducer
  • The Antares f/6.3 SCT Focal Reducer will widen the field of view on your SCT or Mak.
  • For visual or photographic use, "converts" f/10 focal ratios to f/6.3.
  • The Antares f/6.3 SCT Focal Reducer is four element, fully multi-coated for quality images with good contrast.
  • Screws onto the rear cell of your Schmidt- or Maksutov-Cassegrain telescope.


Antares f/6.3 SCT Focal Reducer

Focal reducers are very versatile accessories. More powerful focal reducers are limited to photographic use, but the f/6.3 reducer works well visually or photographically. When used visually, they extend the field of view. Eyepieces used with a focal reducer yield lower-power views. Photographically, a focal reducer shortens your exposure time by allowing more light to reach the film or sensor.

This focal reducer is made to attach to the rear cell of Schmidt-Cassegrain or Maksutov-Cassegrain telescopes. Optically, it consists of a four-element lens that is fully multi-coated for high contrast and resolution.

Antares Product Number: SCTFR

Additional Information

Additional Information

Manufacturer Antares
Barrel Size Thread-on
Warranty 2 Year Warranty

Customer Reviews 4 item(s)

Antares focal reducer coatings
The Antares focal reducer worked satisfactorily to get a wider visual field with my Meade 12 inch LX90. Unfortunately I tried cleaning a spot off from the rear lens, using Mead's recommended lens cleaning solution and plain kleenex, and damaged the, apparently, very delicate coating.
1= Houston, We Have a Problem & 5= It's Out of This World
Review by / (Posted on 7/8/2011)
Excellent for Meade DSI
I have bought this focal reducer for use with a Meade LT6 and Meade DSI II camera. The results are abolutely great: there is no distortion whatsoever in the FOV of the camera, and the gain in imaging speed and FOV is impressive.

It also worked in visual tests, with only some stars at the extreme edge of low-powered eyepieces becoming slightly distorted.

An excellent product.
1= Houston, We Have a Problem & 5= It's Out of This World
Review by / (Posted on 2/13/2011)
Antares F/6.3 SCT Focal Reducer
Unfortunately, I did not enjoy the same results with the Antares Focal Reducer as the previous review.
Using moderately wide 26mm Plossl and 28mm RKE eyepieces, the Antares Reducer produced short arcs of dashed star images in the outer field of view of the eyepieces in a Celestron C5 starting from about two thirds out from center.
Returned for the Celestron f6.3 Focal reducer which shows a relatively flat field and pleasantly tight star images.
1= Houston, We Have a Problem & 5= It's Out of This World
Review by / (Posted on 11/29/2010)
Antares vs Meade comparison
I recently had the opportunity to compare the Antares f/6.3 SCT Reducer/Corrector with the Meade f/6.3 Series 4000 Focal Reducer/Field Flattener.

The Antares focal reducer comes in a small box. Unlike the Meade f/6.3 Series 4000 Focal Reducer/Field Flattener, the Antares has only one cover, which surprised me. You attach the focal reducer to the rear port on a SCT and can keep it covered. But when not in the box or on the telescope, there is no cover for the other end. I wish there was.

With a 2000mm focal length f/10 telescope like a 8 SC or 8 ACF, both the Antares reducer and the Meade reducer should yield a 1260mm focal length f/6.3 telescope. This makes the telescope a faster system with a wider field-of-view and brighter objects, requiring shorter exposure times when doing astrophotography.

Unlike a problem I had with the Meade focal reducer, I had no problems focusing eyepieces or my Nikon D70 DSLR camera on either an 8 LX90-ACF or an 8 LX200-ACF with the Antares focal reducer. I did notice an image size difference between the Meade and Antares focal reducers when using the same setup. When I attached an Off-Axis Guider, the guide eyepiece field-of-view was not restricted, unlike what occurred with the Meade reducer.

For visual work, the Antares reducer worked fine with all the eyepieces (both 1.25 and 2 I tested on both the LX90 and LX200. The expanded field-of-view and the increased brightness of objects really added some enjoyment to the viewing. Depending on the telescope/eyepiece combination, there was no distortion or minimal distortion at the edge of the field-of-view. When distortion was visible, it was not distracting.

I was very pleased in the images I was able to capture with my DSLR when using the Antares reducer. The increased speed of the system made a considerable difference in what could be photographed in the 3-5 minutes that the exposures could be made when mounted in Altitude/Azimuth, without experiencing field rotation.

One thing to keep in mind when using a focal reducer with an Alt/Az fork-mounted telescope is the eyepiece/camera clearance from the base. I found that the maximum elevation on the LX90 and LX200 can vary from 90 degrees to less than 65 degrees, depending on the accessories used.

Based on my photographic and visual tests, I prefer the Antares focal reducer over the Meade focal reducer. The Antares focused in all my test scenarios whereas the Meade reducer had problems reaching a focus with most of my accessories. The physical and optical quality seemed to be essentially identical for both but the Antares model is somewhat less costly.
1= Houston, We Have a Problem & 5= It's Out of This World
Review by Mike Weasner / (Posted on 10/30/2008)
Included Items

Included Items

  • Antares f/6.3 SCT Focal Reducer
Questions & Answers

Product Questions

Are there any focal reducers that reduce the sc more than f 6.3
Will this work on a Takahashi Mewlon 180 or 210?
Will this work with an ETX-90? Or, do I need to use a focal reducer with field flattener such as the Meade product?
Hello, I purchased this product in September for my Meade LT-8 ACF telescope. I already knew that image distortion may occur as this product is not for ACF optics. But, it was okay for me, as I would use it only for visual observation. So, I purchased it, and tested it only on today. There was a problem - this reducer threads onto the rear cell of my telescope ONLY HALFWAY!! Before I made a decision to buy, I had read many user reviews, and no one had reported this problem - I never knew this would happen.

Isn't this product supposed to fit into the rear cell of the most SCT (Meade or Celestron)? I can still observe stars with this reducer half attached, but is this the right way to use it? Am I the only one to report this problem?

Or, can you recommend any adapter for Antares F/6.3 SCT Focal Reducer and my LT-8 telescope?
Will this work with a Meade 10" LX200 ACF?
Hello. Will it fit on a skywatcher 150 - 1800 mak-cass? Does it work well for full frame dslr astrophotography?
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