
Description
The full range is based on a focal ratio of f6.8, fast enough for some superb deep sky photo-visual use and, still have enough focal length for high resolution planetary work both visual and CCD applications.
The tube is constructed from Carbon Fibre sandwich design. Very, very strong to avoid flexing and, zero expansion to ensure the focal plane does not change over long photographic exposures. Being an open tube design and very short, cool down times are remarkably fast.
To assist cool down of the telescope, each model is fitted with three fans, all positioned behind the primary mirror.
Exact focusing across the ODK range is achieved with a Starlight Instruments FTF301B-A Feather Touch 3 Inch dual speed focuser included as standard - pictured below right.
Good images need good optics, all fitted in reliable, stable and precise engineering.
Customers with heavier than normal (4kg+) CCD equipment can add features to the ODK tube to enhance stability.

To produce the photo-visual wide, flat field of the ODK range, we have designed and fitted integrally, a corrector lens system. which ensure both colour correction, coma and spherical aberration are optimised to achieve almost a perfect photographic and visual field. Adequate back focus allows all modern CCD cameras to be used with auxiliary equipment. Multi layer anti reflection coatings are applied to all lens surfaces to maintain brighter images.
CNC machined mono construction secondary spider and trim ensures stability in collimation. Our unique collimation adjustment system enables perfect collimation of the secondary mirror to be achieved, quickly and reliably.
All our ODK primary mirrors are made from Schott Borosilicate Low Expansion Suprax glass (virtually identical to Pyrex), as are all our primary mirrors on all ranges of telescopes. The mirrors are all produced to exacting standards to an F4 paraboloid configuration. How exact are they? Well, we don’t release one to our coating department unless it achieves a surface accuracy of 1/6 wave or better. How do we know when we have achieved that very high degree of accuracy?
We use one of the worlds most exacting measuring devices, a Zygo Laser Interferometer. Take a few minutes and visit the Zygo page and be amazed at just how good this machine is at measuring optics, it can measure optical distances which are smaller than 2,000, yes, 2,000 times smaller than the thickness of a human hair.
Without a Zygo or similarly accurate and reliable measuring instrument, it is impossible to give accurate measurements of an optics’ or telescope’s performance. Only the best manufacturers in the business of making telescopes use them because they are not suitable for mass produced telescopes, they are slow to use and need highly skilled technicians to operate them, it just does not lend itself to anything other than the highest quality, hand figured optics, definitely not mass produced optics to a tight budget.
Primary mirrors are Hilux coated for the highest possible aluminium protected reflective surfaces available.
ODK 16
The ODK16 is in use world wide by amateurs and professionals alike.
Viewing the spot diagrams and other graphic information below will show you just how good the ODK16 presents it’s outstanding specification. As wil all the ODK models we don’t skimp by using just 2 lens elements in the corrector system, we could, but we know from extensive computer designs that there is a real need for 3 elements to give a wider, flatter field. It costs quite a bit more to have this extra lens but, if you compare like with like spot diagrams of an ODK with a similar model on the market, the difference is noticeable and, it’s there for every image you take or visual observation you make, you have the best optical performance available in an Optimised Dall Kirkham, anywhere.
The excellent Starlight Instruments FTF301B-A 3 inch dual speed focuser (pictured below) is available as an add on to enable a strong focusing platform for a wide range of cameras.
We recommend that ODK16 are observatory mounted, ideally on a Paramount or similar mount.
Specifications
Specification |
ODK16 |
Primary mirror diameter |
400mm |
Focal length |
2720mm |
Focal Ratio |
f6.8 |
Tube Weight (inc. |
36kg |
Tube Diameter |
450mm |
Tube Length |
820mm |
BFD (Back Focal |
216mm |
Tube Material |
Carbon fibre sandwich |
Secondary Size |
152mm |
Mirror Cell |
Honeycombe CNC |
Focuser |
3" Add on Option |
Corrector Design |
Multi coated 3 lens |
Flat Field Size |
>52mm |
Spot Size on Axis |
2.4 microns |
Spot Size at Field Edge |
6.0 microns |
Mirror / Tube Cooling |
3 Controllable fans. |
Attachment Method |
CNC machined alum. |
Note: All USA AG 'scopes are supplied with adapters to connect to Starlight Instruments focusers. Focusers are NOT supplied with the telescope but are available as an 'add on'. Images used are for aesthetic appearance only.
Optional Dew Shield available - this is a matching, lightweight carbon fibre addition to help curb the onset of condensation in damp prone atmospheric climes. It is fitted or removed literally in less than a minute and greatly reduces the heavy dew precipitation which can so easily ruin what could be a classic imaging session.

Buy risk-free: When it’s time to trade up you’ll get the most value for your used gear.