We received a question from our customer about our turn-key telescope solutions. It was actually only a short question, but we answer it in detail to show you what kind of benefit it provides, when ordering a complete telescope system from us.
Could you tell me what the OTA rings on the TEC140 in the attached image (from a Baader installation) are. I can see that the outer rings are the Baader heavy duty rings but what out the inner rings (inside the larger, outer rings). Do you sell these inner rings?
In short: Unfortunately we cannot offer these as regular purchasable products.
In detail: these inner rings are always specially made for each complete telescope project where we supply all instrumentation ourselves. Only in this case we have the telescopes all in house for combining, can measure the EXACT tube diameters and fabricate matching contact-pressure rings, to stiffen out the tube(s), so that there is no chance at all that the tube itself is getting deformed from the three pressure pins of the outer heavy duty guiding rings.
Such precaution is mandatory if the owner wants to do unguided imaging, since otherwise the tube will get deformed differently when the instrument is pointing east or west. Surely this can be remedied partially by doing a proper mount model. Alas – temperature drop causes different flexure, due to making the metal become stiffer across the night, and no mount model is set up to cope with temperature related flexure changes. This would require about 10 mount models per night.
We had offered these inner rings for a while for some telescope brands – but it resulted in an never ending nightmare. Tube diameters are never according to specs, different OTA-production runs will have slightly different tube production runs – and this means changes again. New telescope models come out all too frequently and – last but not least – - the owners have no means or technical knowledge, to supply absolutely correct measurement as is required for this task.
In the end we had to stop offering this service because we got almost every second pair of inner rings back for reworking.
So by now we only and exclusively do produce such special inner rings (and many other, more hidden parts for stiffening out such an assembly) in a bespoke fashion – when we do supply the complete equipment and have every bid of the instruments in house that need to be combined. Then we do the complete "telescope craddle" for one or more instruments and can determine the ideal "balance point" of telescopes and main accessories – and combine everything in an ideal fashion, to exclude any flexure from the combined telescope system.
The video to the left shows this kind of work on a telescope installation in our house in a time-lapse, as well as all other neccessary steps until a complete telescope installation (or in this case also with Remote Controlled AllSky dome) takes its "First Light".
This is NOT CHEAP, as it takes many ours of machinist time, in order to fiddle around with the equipment and put everything together and produce a whole number of specialised parts until it all fits together nicely. But in the end, it is worth the cost and wait – at least according to our customers.