Mandy D

Yes, agrred, but for titles and emphasis it is seen as OK. So why not go with all-caps in your correction, or is that for empasis? Did you see the other thread with the original title that I linked you to? It shows under "Similar Content" at the bottom of this thread.

We have to pose questions in order to answer them. A hypothesis which is currently unllasifiable may become falsifiable or, indeed proven correct, tomorrow. Did not the alchemists attempt to turn lead into gold? Can we not now do this, albeit by other means than chemical? As an engineer I understand all too well that RF works and we engineers use that which works. However, scientists are in a different class to engineers and are looking for the unknown. Sometimes they postulate what might be and set out to search for it. Yes, this is usually founded on what is known and requires adjustment to make it fit with the facts, hence why we currently have a postulate regarding the existence of dark matter and dark energy, yet no-one has found lab samples of either so far. It may end up not existing and in it's place will be found new laws of physics or adjustments to existing ones. It is very clear to anyone with a good grounding in physics that much remains to be discovered and that surprises await us. So, why not dream and consider what some of those things may be?

Well, this is wierd, there appears to be a longer thread out there still with the annoying title: New title is still irritating as we now have the first word in mixed case and the rest in all caps! 😉

Yes, we agree on this point, but a species more technologically advanced and with greater understanding of physics than us would not necessarily be bound by our limited knowledge and 'may' indeed have access to super light speed comms and travel. Indeed, if they were truly space-faring on an intra or inter galactic basis we may have to assume that they do not use radio for their communications. it would be a tad impractical, would it not?

The mathematics of relativity only prohibits non-massless objects frm travelling at the speed of light. You can solve those equations for any higher velocity as this does not lead to a division by zero error, hence relativity does not prohibit FTL. How you would get to those speeds without passing through the "light barrier" no-one yet knows. There may be physics that we do not yet know. The victorians declared that the end of physics was in sight, yet here we are over 120 years later and still cannot see the light at the end of the tunnel.

Any technology which is sufficiently advanced will look like magic. We humans currently use radio waves because we haven't yet come up with anything that propogates faster. Are we really so conceited as to think that there is no more advanced species than us in a vast cosmos? I'm sorry, but I cannot agree that we are at the forefront of everything in the Universe. I would agree that over-unity machines and things of that ilk will never be possible, but I see nothing preventing FTL communications.

Finally got a nice dry day and a bit of sunshine to test the new pier. With the RC6, focal extender and an extra 50mm of extension pieces plus a DSLR it was certainly not the weak link in the chain. With that load the Hercules mount is beyond it's sensible limit and would not actually hold the RC6 and D800 in the horizontal position with a single counterweight, but there was no movement in the peir.

Yes, all of the above. I remember the paper tape reader/puncher and bi-directional reel to reel tape drives using half inch tape which was great for making extra long VHS cassettes from as a physics teacher showed us! Yes, the 14 inch Winchester had removeable platters, a stack of 5 or 6 discs (sorry, disks!).

Yes!!! 😁

Honeywell 516 mainframe with magnetic core memory, 14 inch winchester drives and, of course wire-wrapping everywhere and only 16 k of RAM, all programmed in octal. That was my first (and last) mainframe experience.

The way I read that made me howl with laughter! 🤣 So we can expect more? Cool!

Thanks, @DaveL59 I can't wait to try it out. Just need some clear sky, now!

Pier Project: Phase 4 I finally found time to assemble this to the tripod complete with the Hercules AZ mount. I'm now just waiting for the weather to clear so I can get it outside and mount the RC6 on it to try the new Barlow and focal extender.

Thanks. I'd been taking 20 thou cuts with a carbide tool when facing and roughing out the socket with no vibration at all. It was just the flimsy boring bar when I was finishing the bore. Having the tool below centre height certainly wasn't helping either, but I had no alternatives. The bar in your link looks like what I need and is certainly cheap enough.

Sorry to hear about the problems. Iceland is fantastic, a place you will never forget, there is nowhere else on Earth quite like it. I can't help with the astro side, but here are some "must visit" places. Thingvellir: site of the world's oldest parliament. a valley being pulled apart by tectonic activity between north American European plates with a river and huge waterfall. Geysir: erupting hot springs. Gullfos: the European Niagra of waterfalls Hallgrimskirkja: the huge and dramatic looking church in Reykjavik. Amazing pipe organ inside. Blaa Lonid (Blue Lagoon): over-rated but maybe worth a visit just to say you've been. Could be good theraputically for your wife to bathe in the waters, though. Reykjanes Peninsula: You will see this on the way from Keflavic Airport. Very dramatic scenery. NASA trained Apollo astronauts here as the terrain is so alien and lunar like. Kringlan Shopping Mall: used to have a 4 metre tall stuffed polar bear on display at a sporting goods store. Store went bankrupt long time ago and bear was list for many years. Has been found recently and is on display somewhere in Iceland. Google will find him. Vatnajökull: Europe's largest glacier. Reykir: site of Europe's largest banana producer! The Perlan: Iceland's most famous revolving restaurant sat on top of the water storage vats that feed Reykjavik. Trains: Iceland has no rail network, but has a steam train near the harbour in Reykjavik! It goes nowhere. Food: Fish, of course! we ate at a small cafe in downtown Reykjavik and had the most amazing lobster soup. Everyone is so friendly and nice and most speak excellent English.

Pier Project: Phase 3 Sometimes everything goes smoothly and without a hitch. Then there are those occasions when nothing does: Those days that engineers call "normal days"! This has turned into one of those days ... As you can see from the last photo below, the pier fitted on the tripod perfectly and the adapter fitted on top of the pier. Well, at least, I thought it did, but then on closer examination there was a 0.5 mm gap between the outer mating surfaces. It had to be the M12 screw joining the two pieces that was too long. It really could not be anything else, could it? The socket on the new pier, into which the spigot on the adapter fits was at least a millimetre deeper than required to accommodate the spigot. OK, no problem, just tap the hole in the pier a bit deeper and all will be well, I told myself and try a new screw. For some reason the new screw was binding on the threads in the adapter, so I ran the tap in again, but to no avail. I tried some M12 nuts on the screw and they spun up and down the thread without a problem. The old screw still went in fine, so I ran a different M12 tap in and eventually got the new screw to go in. Great! Problem solved. Nope! Still the same gap as before, so I measured the spigot and socket to check that I had clearance on the depth. Yes, I did. So I machined the socket a bit deeper as it still would not fit, as I was now running out of ideas. Would this cure it? No, of course not, the socket was already deeper than it needed to be! So, I took a closer look at the mating face on the adapter and found a 0.5 mm high burr all the way around it close to the spigot. Put it back in the lathe, machined it off, et voila! As they say en France. I was hoping to get this lot assembled and photographed tonight, but it looks like tomorrow is the day for that, now! The photos show the pier assembled on the tripod as it was before I fixed the problem.

It is 7075 grade (high strength) aluminium alloy. It probably is overkill, but it was a lump of metal I had to hand and should give "adequate" stiffness in this application! I'm glad you are njoying the pictures. I will be posting some of the complete assembly on the tripod later and, if the weather ever clears, with the telescope mounted and pointing at the sky.

I'd love to, but I'm really not that skilled at machining. I am seriously thinking about how I might make a solid and effective AZ head, though, but doubt it will come to fruition. This pier took me to the limits of my machining skills and a bit beyond. It was a real learning curve.

Pier Project: Phase 2 - continued More photos. These show the finishing process for the bore and tapping of the M12 female threads. Note the judicious use of card between the chuck jaws and the aluminium to prevent damage to the smooth finish. I learnt from machining the original adapter that aluminium marks all too easily!

Pier Project: Phase 2 I finished machining the pier this morning. The 65 diameter x 5 mm deep socket to receive the spigot on the adapter that goes under the Hercules mount caused some problems as I don't have a decent boring bar, so most of the cutting was done with a normal carbide tool, after drilling a 3/4" hole with a flat-ended drill. The finishing of the bore was done with a flimsy boring tool that vibrated all the time, so the maximum cut I could take was 5 thou. I really must get a decent boring tool. I have a nice tapping head, so tapping the M12 threads in each end was very easy at 40 rpm. I could have gone faster, but I'm always terrified of the tap shearing! The photos show the machining process for the socket.

@vlaiv Looking at this from an engineering perspective, so I may have some astro points wrong here, would it not be preferable to use multi-stage reduction? Two stages with 3 mm pinion and 150 mm wheel would give 2500:1 reduction. The 3 mm pinion would certainly be preferable to 1 mm. Combine this with micro-stepping and you would achieve you a resolution of 0.081 arc-second, if my arithmetic is correct. I'm not sure about spring loading it, but a rubber tyre on the wheel and a steel pin should provide an adequate friction drive with minimal backlash if the rubber is thin enough.

The Skywatcher 2" tripod I have has an M12 male thread and the Hercules mount has a 3/8" UNC female thread, so I previously machined an adapter to convert between the two, using a 3/8" stud in the top of the adapter. Now I just have to machine the two ends of the new pillar to match the spigot on this part and the recess on the tripod, drill and tap both ends M12 and fit a stud for the bottom of the adapter. Then the system can be used with or without the pillar and will allow compatibility with any 3/8" threaded photo equipment. If I fit dowels at the top and bottom, it can also be used with astro mounts. You can see the machined adapter under the Hercules mount in the photo.

With the planets getting higher in the sky and the imaging train on my RC6 getting longer, it has become difficult to get to the eyepiece of my DSLR, so I've decided that a pier extension for the Skywatcher 2" tripod is required. I have a piece of 4 inch diameter aluminium bar about 250 mm long that is doing nothing so I figured it would do the job nicely and sit between the tripod head and my existing homemade mount adapter. Hopefully, it will be stiff enough! 😉 This afternoon I faced both ends of the bar and cleaned up the outside, but now I need the adapter, which is at home, for the rest of my measurements, so will continue this project tomorrow. I'm going to drill and tap each end of the pier at M12, machine a spigot on one end and a socket on the other to keep everything nicely aligned. The photos show phase 1 of the project. More to follow!

There is a full discussion on the topic of image inversion in a Newtonian reflector here: It seems to cause a lot of confusion, even in here.