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APM Triplet APO Reducer

APM Triplet APO Reducer
Price:  £499.00(Inc. 20% VAT)

Product Code:  APMREDSMALL
Brand:  APM Telescopes



In stock, Shipped in 1-2 working days

APM Telescopes

The Stunning Triplet APO Reducer!

The APM Reducers are a fantastically simple way to give you a second optically superb telescope at a fraction of the price. A reducer, as its name implies, "reduces" the focal length of your telescope by a set factor. In the case of the APM APO Reducer this is 0.75x. So an 800mm focal length scope becomes a 600mm. This has two benefits. The first is that you get a second telescope with a wider field of view for imaging objects that would otherwise be cropped. Secondly, it effectively increases the focal ratio. So our 107/700 F6.5 Apo Refractor becomes a 107/525 F4.9! This allows for significantly reduced exposure times or increased light capturing ability, depending on your imaging needs. 

Of course, performing the reducing function while maintaining the colour correction and other optical criteria such as spherical aberrations, coma and astigmatisms is extremely important. There is no point gaining the benefits of a reducer if they lead to poorer telescope performance. A reducer has to bend light in order to do its job. Therefore good optical design and quality components are an absolute must. In addition to this a Reducer must be matched to a particular telescope type. Unlike a simple field flattener which will work equally well on an 80/480 F6 as it will on a 175/1400 F8, a Reducer has to be optimised. Many Reducers on the market are optically poor and affect the original performance of the telescope significantly because they attempt to be universal. This is not acceptable in an APM system.

Fortunately at APM we know a thing or two about optical and telescope design. We offer two types of Reducer, a large and small type. These differ in the size of the flat field image they offer. The smaller one provides a 40-42 mm image circle, the larger version, 52 mm. All of our Reducers are designed by the respected designer Massimo Riccardi and utilise low dispersion FK61 ED glass in a triplet configuration and offer true Apochromatic flat field performance. They are optimised for specific APM models and are also suitable for use with other manufacturers products where specified.

Each of our reducers are supplied with a Tilt adjuster. This may not be required. However, because of the critical nature of alignment when using a reducer, we provide one so you are always guaranteed the very best performance. This is the APM standard.

We also supply our reducer with the necessary adapters to allow you to attach your camera or offer accessories. We feel this is what you should expect. Unlike other manufacturers, we don"t expect customers to invest in one of our products only to find they have to spend more money buying an adapter to attach it to the rest of their system.

The APM ED Reducer is available in two versions. The small and large. The small can be used with focusers from 2.5", the large from 3". Mounting is either on the end of or internally within the focuser body. Please note that using a reducer requires your telescope to have the necessary back focus. If in doubt, you should contact us with details of your telescope before purchase.

Both APM Reducers are supplied with Adjustment flanges and M48 to T2 adapters. The Small Reducer also comes with a multi-function thread adapter to permit fitting to different focusers, while the Large Reducer includes an M82-M48 adapter.

The Small Reducer costs £409.00 while the Large Reducer is £499.00. We also provide special adapters for use with large focusers such as the 3.5" Starlight Instruments Feathertouch and can provide other adapters to order.

Notice how the reducer specification must change to work correctly with different focal lengths and aperture sizes. Unlike "universal" reducers an APM Reducer maintains image quality!

We currently offer reducers to fit all APM Apochromatic Refractor Telescopes. These are designed for use with either the 2.5" or larger focusers or a 3" and larger focusers.

We also offer reducers to fit the 10" F8 GSO Ritchey-Chrí©tien and the Skywatcher Esprit 150mm F7. Our reducers will also work on other Apochromatic Refractors which have the same focal length / ratio i.e. 80/480 F6. It is advised that you contact us prior to purchase to confirm which Reducer is correct for your telescope.

Common Specifications

  • Type - Apochromatic Reducer
  • Lens - Triplet Cell with FK61 ED Element
  • Coating - Fully Multicoated
  • Magnification - 0.75x
  • Camera Connection - M63 or M82
  • Telescope Connection - M63 or M82
  • Length - 72-98mm
  • Material - Aluminium
  • Back Focus - Model Dependent
  • Corrected Field - 40-52mm


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