page contents

ASA 12N-OK3 12" F3.6 Astrograph - LOWER PRICING!

ASA 12N-OK3 12" F3.6 Astrograph - LOWER PRICING!

can be shipped within 90-120 days

Price includes VAT, plus delivery



ASA Astrographs – High Quality, Stable, Perfect

ASA Astrographs have been developed with the help of experience from some of the leading astrophotographers of our time. The correctors are designed by Dipl. Phys Philipp Keller and have been perfected by use of high end materials. ASA Astrographs offer perfect image performance over a large field of view, are lightweight but stiff and have very fast focal ratio.

The tube is produced using high grade carbon fibre with internal velvet flocking. The carbon construction offers very low thermal expansion and great rigidity. This ensures that focus is very stable and there is no detectable tube flexure. As standard, the telescope is supplied with the OK3 3" Motorised focuser which has a load capacity of 3kg.

The ASA Astrograph has a very fast focal ratio. This offers good signal to noise ratio with short exposure times. Through the uncompromising optical design of Philipp Keller, the corrector lens system deployed can handle large format sensors. Even the largest sensors will have perfect correction all the way to the corners.

The N-Series Astrograph employs a parabolic main mirror with a focal ratio of F3.6. by switching the corrector lens system, the focal length of the telescope can be shortened or extended with minimum effort.

With the supplied 3” Wynne corrector, F3.6 is achieved. By using the 2” Reducer, this is lowered to only F2.75. By adding the 2” Barlow, the focal ratio increases to F6.8.

All ASA Astrographs are manufactured from superior Suprax glass and polished to an accuracy of P/V = 1/7 Lambda. The coating is an advanced aluminium coating employing enhanced multi-layered overcoats to increase the reflectivity of telescope mirrors to 97% over a wide range of the visible spectrum. All secondary mirrors are made to the same specification.

On request, premium Astro-Sital zero expansion ceramics polished by LOMO Optics can be ordered.



Aperture                                  12” / 300mm

Focal Length                            1140mm

Corrector                                  3” Wynne

Secondary                               120mm

Focuser                                    OK3 Motorised 3”

Tube Length                             990mm

Tube Diameter                          360mm

Weight                                      16kg


Performance with Correctors                                            

                                                Lenses       Image Circle        Aperture Ratio           Weight

3” Wynne Corrector               3                    50mm                         F3.6                      780g

3” Reducer                             4                    30mm                         F2.75                    720g

2” Barlow                               5                    35mm                         F6.8                      315g


We also recommend

Prices includes VAT, plus delivery

Browse this category: Newtonian Astrographs