iapa

my work here is done

Seems that one Konstantin Tsiolkovsky came up with the idea in the very early 1900s. As well as the basic three stage design still used for rocketry, proposals for hovercraft and the formula establishing the relationship between change in the rocket's speed, exhaust velocity of the engine and mass of the rocket. All good, until his involvement in the October Revolution and subsequent involvement in the Soviet era.

Do Arthur C. Clarke or Stanley Kubrick now appear on the “bad people” list for using the rotating ring with spokes design? 👹

QHY268M Back focus is 12.5mm per Modern Astronomy. the ASI533MC has 6.5mm back focus per FLO. So that the source of 6mm of your difference.

If you have had it apart already, I’d remove any shavings, clean rack and pinion with a degreaser. apply a little lubricant - I’ll leave others to suggest which. Retension; SW don’t provide much in the way of help, but GSO make these for ORION as well as SW. So, their manual helps. from memory, four screws hold cover plate on, and there are three other adjustments to tension the focus mechanism, the left and right should be loosened and gentry tighten tun til just in contact, the middle adjust the tension to stop the tube slipping. Can try to look thing out again if necessary.

Neither the unbranded refractor, nor the much better reflector are much use. See commentary above. The Skywatch StarTravel ST80 has a decent price and performs far better than is generally expected in the price range. This is light enough to mount on a decent camera tripod for observing. For imaging you could easily fit a DSLR to this and track the stars by eye - old time fashion. It’s good for observing, and with a motorised go-to mount, can also provide good results imaging. The original Skywatcher Star adventurer would carry this with a DSLR easily - i did for about a year. Read lots first, Sky and Night magazine has well written reviews. There’s some good stuff on YouTube; lazy Greek, backyard astronomy, astrobiscuit and others. Watch, absorb, ask more questions.

I just like to minimise strain where possible, especially where motors and gearing is involved. Part of my OCD. The worst that can happen surely, is the clutch slipping and the OTA colliding with other metal work? Not currently an Alt-At user so unsure of clearances these days - but in the past I certainly did have my Alt-Az clutch slip and the OTA hit the tripod, that was an Newtonian tho’ and longer that the SCTs under discussion here.

Make sure the cotton wool is from a well known manufacturer and carries the BP* (British Pharmacopoeia) mark, but note that even then there may still be some husk in the product. * other areas such as India, Europe and Japan have their own equivalent.

If you are looking at handles, then, I believe that @JeremyS is the god of handles.

Looks like the OTA is a standard Celestron 6” SCT, so t-ring https://www.celestron.com/products/t-ring-for-canon-eos-ef-mount-camera you may also need the t-adapter to get sensor to the correct position. https://www.celestron.com/products/t-adapter-for-schmidt-cassegrain-telescopes The above is what i have on my Celestron 8” SCT OR, you could get an M42-1.25” nose piece and the t-ring. the first combination would be my recomendation. FLO will sell all of these, as do many other resellers.

I appreciate that the 12lb 8oz OTA is a significant weight for a wee lass of 5’ 6”, so you might consider something like the Oklop carriers? Or the more expensive option from Celestron. If you choose that route, I’d open the bag and dust cover once indoors to let it breathe and dissipate dew. Personally, these days I put a Telegizmos cover over and take things in in the morning. I doubt that Celestron recommend moving the complete rig, and having read their manual for the Evolution, I can’t see that recommendation. With a EVO’s combined weight in the region of 3 stone, these days I’d balk at that (6’2” build like brick kludgie), 5 yrs ago carrying in the 60lb tripod/mount/OTA was easy - then. After getting the tripod where I wanted it, I’d glued some 1p pieces on the patio where the tripods legs went - makes set up quicker. In the lawn, I dug in three bricks just below the grass level- so smallest edge was up, and again marked leg position. Another thing I did was to add all attachments to the OTA when on a table, and balanced it on the dovetail on a round pencil, and marked pivot point with a fluorescent marked - only needs a dot. Then marked the middle of the mount plate - quick and easy initial balance which should be enough for observing.

Did this experiment progress any further?

+1 for Telegizmos 365 My CGX-L has been unused and under one of these since May 2020. Minimum temperatures -9C, max 26C All i did today was demolish some arachnid housing just under the top plate. all knobs move freely. One hex head bolts has slight rust, and there is a small flake of paint missing. A second mount was also under a Telegizmos, it also survived well.

Best tip from the programme: top of the list of things to do - remember to remove the frigging lens cap!!!!!

Horizon is nowhere as good as it was 40yrs ago when it seems that it was more in depth.

For my AVX / C8 SCT rig I use the ZWO 12 5A PSU to power the ASIAIR Pro. This provides power to imaging camera ASI 1600/183/284 Cooled. EAF (the newer USB powered version) and filter wheel data and power are via the imaging camera USB hub. 8” dew heater power is from the No. 2 power port. No issues to date with power. Currently power the mount from a separate 12V ZWO PSU, but did run my AVX from the ASI AIR Pro for a while. The only reason I use separate power is that I have 2 x 12v Phazer batteries from Halfords for mobile use. CGX-L /10” Quattro was managed from Pegasus Advanced, 1 USB hub provided power to a stick PC. Filter wheel and focus motor data via imaging camera USB. Mount, focus motor and imaging camera powered from 3 of the 12V ports. Dew heaters from the relevant ports. Overall power from Pegasus PSU. The power stick ran SGPro, PHD2 for scheduling and guiding.

If 90mm triplet refractors with 2.2 arcminute FOV are good enough for JWST, are they good enough for us plebs?

Reading a number of repeated threads on CN, and elsewhere, a number of people have reported similar to Celestron, and were also advised “we’ve not seen that before”. Hmmmm.

What thickness acetate sheet did you use? Are you saying the acetate will hold itself in shape and in place? Or am I missing something somewhere? Also, what was the flocking material? My paint if flaking off the SCT’s interior so, need some sort of remediation.

I’ve found this: https://www.cloudynights.com/articles/cat/articles/new-articles-in-monthname/cleaning-and-modifying-the-c11-beast-part-1-removing-the-corrector-plate-r2476 which took 3 days for the man to do, without recollimating.

I’ve not used the C8 in anger for some time - at least 2 years. When I took a look at it, through the corrector plate, I noticed some large dark areas on the mirror, check corrector and noting matched. Then I noticed the Matt finish on the inside of the tube is flaking off. Any thoughts as to how best to deal with this? At least the corrector plate needs a clean anyway, but appears to have no scratches of marks, ditto for other optical surfaces.

I use these https://smile.amazon.co.uk/gp/product/B004R255VQ/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I’m with the other responders; use a mains extension with integral circuit breaker.

I am finding myself wondering why I even have some of these there must have been a good reason at one point. Of course, there are the guide scopes as well as the finders.

The one thing I would say I that you should use the recommended ZWO PSU for the ASI Air Pro, and separate power for the mount. I have found that the power demand for imaging camera, guide camera, EAF, and dew strip (using Lynx Astro DC male to RCA adapter cable) is easily met by the ZWO PSU. Sometime ago I posed current draw for these, I'll try to find it.