Dall Kirkham Optical Tubes

[Radar]

Not sure how these rank against RC scopes, but they sure look interesting.

http://www.orionoptics.co.uk/ODK/odkrange.html

http://www.orionoptics.co.uk/Resources/odktubes.png


Apertures available are: ODK10: 250mm ODK12: 300mm ODK14: 350mm ODK16: 400mm
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.
ODK10rearThe 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 our newly introduced Precision 3” Crayford Focuser featuring a 10:1 reduction drive included as standard and, as an option; we can include our electronic drive system with variable speed focusing control. Good images need good optics, all fitted in reliable, stable and precise engineering.

So many toys, not enough money!

Ray

[Kokatha man]

:hmm:.....the old DK-Cassegrain's were great planetary scopes, but their f ratios were much higher than these babies.....have seen some of the old ones used for planetary imaging with fine results.....I see these use corrector lens etc for the Deep Sky imaging useage.....pretty pricey too....!:eek::wink::smile:

[Radar]

Yeah interesting telescope. I like how cooling fans and field flatteners are slowly becoming standard on telescopes these days. Not sure what the big difference is with the DK design, but if their price is an indicator I'm sure they go deep.

Ray

[Kokatha man]

.....talking right off the top of my head here Ray - I seem to have forgotten at least as much as I remember:duh: - and I'm sure someone will correct me if I'm off-beam.....but Dall-Kirkham Cassegrains (which have been around a long time) employed elliptical primariy mirrors and spherical secondaries which I believe made it easier to figure/create said in the first instance.....modified DK cassegrains have lens elements in the optical train (I think between the 2ndary and primary:confused:) to create their own specific field criteria.....reputed to be considerably superior to R-C scopes.....so perhaps these new "whizz-bang" versions are really worth the "bang-for-bucks" prices....!

[Radar]

reputed to be considerably superior to R-C scopes.....

Wow, interesting stuff. Not that I can afford one but I'll have to keep my eye peeled for images taken with them. For some reason the types of telescope optics on the market always interests me.

Also interesting that they use an elliptical mirror.

Ray