SnakeyJ

All the way from Sweden and deposited on my door step by the courier three days earlier than expected - As it was palleted and weighed almost 70kg, it was left out in the rain until I got home from work!

The box was a little soggy, but it was well packed and wrapped in polythene, so no problems (other than a long explanation to my wife) - Fair to say it is a bit of a beast and I shall look forward to hoovering up some stray photons once I can get it mounted and balanced in my obs.

Just looking around and the light curve from https://www.aavso.org/vsots_alphaori and there seems to be quite regular dips down to around 1.5 and a more exception dip to almost 2 in 1948 ish.

Very unlikely, but It would be quite special to see such a close SN in our lifetime - it would also be sad to loose an old friend of some 50+ years in my case.    

Quite a good article at Sky and Telescope from new years eve, but the light curve they plot for the last 50 years.   If we're fitting 1.66 now it is hitting an exceptional low.

6 minutes ago, paulastro said:

Here's the catalogue entry for it.  The catalogue is from 1971.

HI Paul,  Many thanks for finding and posting this - wonderful to see the original specification and pricing.     Over £ 4,000 pounds in today's money...

6 minutes ago, John said:

The mounting used was really massive - Sir Patrick Moore used one on his 5 inch Cooke refractor:

 

Now that is a thing of beauty and very good provenance.

Just now, John said:

Oh boy, does that bring back memories !

My school had one of those in a dome which we used when I joined the after school astronomy club. It seemed a giant of a scope when I was 12 years old

That was 1972 so your dating would be about right Jake

It does smack of quality, the mirror looks to be 2.5" thick!     I've never seen a mount quite like that, but I do like the double D lines..... slightly reminiscent of the robot in 'Forbidden Planet'

No connection to the seller, but this looks really interesting, with a very heavy and unusual looking EQ mount.    I would guess it's early 70's, but would love to know some info on this.

https://www.ebay.co.uk/itm/184162508130

Sadly I don't have the time or space for another project, but hope this finds a good home.

I love that, a most well deserved AAPOD and hopefully more to follow.

16 hours ago, Rusted said:

d) White Hammerite paint is the cheapest form of stainless steel.  <Arrowed.>

Excellent point Rusted - I have a lot of assorted cast iron weights of various makes and colours and will invest in some white smooth hamerite and a few cheap brushes

15 hours ago, Ben the Ignorant said:

This is one of the A2 bolts that's been enduring the weather for at least twenty-two years, that lamp was already converted to sodium when I moved into this neighborhood. No one to clean it up but shiny after all those years. Note that there is some lateral color because the photo was taken through a Baader Hyperion 10mm, which are notorious for that, but the Sun's reflection on the bolt at the center causes no fringing, thanks to the very good correction of the FPL-51 80mm f/7 doublet.

The clamp is either aluminum or stainless, too, and didn't suffer any corrosion either.

Thanks Ben - amazing condition given 20 years exposure to British weather.   I'm sure that 20 years will see me through.

Interesting that the street light, a traditional bane of  UK astronomers, can prove to be such a useful tool.   In my area we changed over to LED some 4-5 years ago, I expect the contractors will have scrimped on fittings, but will take a closer look now!

2 hours ago, Chriske said:

Very hard to machine indeed SS.
That's why I rarely use it. I use brass instead. Polished it looks awesome.

It certainly would look awesome, but a fair amount of polishing to keep it gleaming - would look great for that cyber punk effect (like the Great Weatherall Refractor below) and a little denser than SS, but also fair bit more expensive to buy.

The stainless surfaces up nicely with Carbide tooling on my lathe and no problems so far with drilling, boring and tapping ops - though I did use the feed and suds pump for the finishing cuts.

On 12/07/2019 at 00:16, JamesF said:

Not seen you posting for some time, Jake.  Good to know you're still here

My gut feeling is that it's better to have more weight closer to the mount than less weight further out in order to reduce the moment of inertia (which varies with the square of the distance from the axis of rotation, IIRC).  You've got a lot of weight there though.  What's on the business end of the mount?  The OO 250?

James

Hi James, and thanks for your response - I do still dip in and follow the forum and progress on your obs, but have been busy with my daughter and very little time and energy for astronomy.   I have managed to sort my bijou 8x8' workshop and trying to get my new planetary setup running.

My rig is quite unweildy, with an OO 14" swinging on old style CGE Pro, within a 2.2m pulsar dome.   To shift the OTA CoB forward sufficiently to operate in the dome, I had to add almost 5kg of lead flashing wrapped around the front of the OTA.   This is held in steel rings between two 14" losmandy dovetails.   All up with camera, ADC and Barlow's, just under 30kg.

I'm hoping the OO ultra grade optics, smaller CO and open tube will give the C14's a run for the money and have a couple of years yet to tweak before Jupiter, Mars and Saturn become decent UK targets. 

Certainly not expecting this to perform for LX imaging, but with CMOS sensitivity improving, exposure rates commonly over 100fps at f15-f20 and the rig reasonably sheltered from the wind, it should be stable enough.

Just now, fozzybear said:

we use 316 at work but would cost a fortune to ship an offcut to you we waste a lot.... but recycle it... anyway, how about a steel billet and then cold glavanise it (spraycan) cheaper?

316 is good, but much more expensive and harder to machine, though a few inserts or taking lighter cuts makes little real difference to me at home.

Cold galvanise, paint or electro plate all good enough for me, but it would be nice to do stainless if I could find a bit.  

I managed to source some 32mm diameter 304 grade SS at a sensible price for another project, but have enough left to make an extended counterweight shaft for my cge pro.

Looks great and machines nicely - pretty sure it will do the job and stay shiny in my obs, but just wanted a second opinion.

The original is 15.5" X 1.25" including turned down externally threaded end at 1" X 16tpi  but thinking I might add 7-8" and reduce the number of weights (currently 25kg, original Celestron 10kg, 2 X SW 5kg and 2 X 2.5 iron gym weights).

(BTW - I'm still looking for some cheap/free 8" SS billet bar - about 10" should suffice and a powered hacksaw/ bandsaw.... )

There's a v3 synscan controller on Astroboot at the moment £ 77.50 less 10% (Snow Sale Still On!)  - http://www.astroboot.co.uk/AstroBoot

2 hours ago, Gina said:

I too have the problem of wanting to do high speed capture, not particularly for planetary though that is in my thoughts for the future, but for solar Ha imaging where the same applies.  I have an Ethernet feed to my observatory and 1Gbps capability so could capture what amounts to video indoors.  Alternatively a USB3 computer of some sort in the observatory could be used for capture.  There are several Linux based image capture applications.  KStars/Ekos/INDI will certainly control domes.  There is another micro-computer board like the RPi that has USB3 - forget it's name ATM.

I will definitely run in some fibre when I pull in the permanent power feed, so this will be an option.   I shall have a dig around re other RPi like boards, but nothing cheaper than what you already have and quite happy to run my laptop headless, with control back in the house - It might even be easier to run this with a remote KVM extender and I can switch this with my home desktop inside in the warm!

1 minute ago, Gina said:

I too am virtually Linux only and use KStars/Ekos/INDI together with my own hardware for remote and auto-focussing using the Raspberry Pi 3 instead of a laptop in the observatory, right on the pier top.  I'm currently adding to my tutorial blog - Setting up a Raspberry Pi for Astro Imaging and Control - Ubuntu Mate

Thanks Gina - I would love to do this and probably makes a lots of sense for deepsky, but I don't think the Pi3 would provide enough grunt (USB3 connectivity or the i/o to SSD) for high speed planetary imaging.     However I could run all of this on Linux on the laptop and firecapture will run natively on Linux (limited support for cameras, but does cover the ZWO/QHY).    I will have a read through your blogg as I do have an idle RP3+ available and was thinking of using this to control my dome.     

18 minutes ago, tekkydave said:

I suspect the problem may be down to FC refusing to use non-64bit drivers. I'm not really supporting this project anymore and I dont have the tools to make changes to the driver which requires windoze ( I only use Linux these days).

If you get hold of the latest free copy of MS Visual Studio you can recompile the driver easily for your platform. All the source code is on the AAF Sourceforge site.

Hope that helps.

Dave

Thanks Dave - I didn't realise the source code was available for this - I might just have a pop at this as the focuser works beautifully and it's far more satisfying to DIY it (rather than forking out £300+ to Baader/Moonlight/FT).   

33 minutes ago, tekkydave said:

I think it's 32-bit but it should work fine on a 64-bit o/s. 

It does and the AAF2 is working fine, but Firecapture x64 won't play with it and gives an error about non compliant 32 bit drivers!    I'll try and screenshot the error tonight, but I still have the option of using AAF2 as a separate program or going back to x86 version of FC, so not a show stopper but wanted to check.

To be honest I'm not sure if there is any real advantage in using the x64 version of firecapture, as USB3 and i/o to SSD are probably the main bottlenecks  affecting frame rates at larger ROI's.

@tekkydave - Dave does your 2.5 version include an x64 bit driver?

I upgraded my version of Firecapture to try the x64, but it doesn't play with the original ascom driver.   Not the end of the world as I can still use the AAF2 software to control the focusing outside of FC.

I've been using the original version of this project for the last four years, but will update and build a new version now for new monster planetary setup!

3 hours ago, martin_h said:

I have foxes camping under my obs, one end is 2 feet above ground level, no problems so far but the do get the blood pumping at 3 am when the decide to have a fight!

I'd be all up for the foxes, or badgers, hedgehogs (pretty much anything other than rats or a big wasp/hornet nest that closed the observatory.    However, having kept chickens briefly on multiple occasions, I totally understand James taking sensible precautions to dissuade the foxes 

9 hours ago, JamesF said:

I find myself tempted by a "Todmorden pier" now I've done a bit more reading, especially if I could find a suitable adhesive for the blocks as well as bolting them together.  It achieves my goal of being removable which is good.  I want about 900mm above floor height for the top of the pier, so I'd have to bring the foundation very close to the underside of the floor, or get the disc cutter out and use two and a half blocks instead.  I reckon that would get me close to a total pier height of 1200mm which was what I was planning in the first place.  Given a suitable length of threaded rod I could even embed it in the foundation and run it all the way up through all of the blocks to tie them all together.

And if it didn't work out I could always unbolt them and mount a normal steel pier held in place using more rod with resin anchors.

Doing a quick search suggests the actual dimensions of the blocks are 215mm x 440mm and they weigh about 25kg each.

I shall ponder on this overnight.

James

I'm pretty sure that any of the waterproof foaming gap filling adhesives would do a good job with concrete block, as it's such a large and pourous area to join (gorilla glue?).   Otherwise a tube of masonry/fixing epoxy resin should give a bomb proof bond.

I've bolted my piers down on 16mm rebar - galvanised as I'm sure this will still outlive me!  When I moved out of the last house I bolted the roll off roof down, took away the runners, removed the pier and ground the bolts off with an angle grinder.    The shed conversion took 2-3 hours, or about 1/50th of the observatory build time and the new owner was very pleased with the posh shed!

Glad to see you are finally getting around to this build, it has been a long time a coming.    Quite a challenging site for a build, but will be good to have a raised deck/base as the floor, which should keep you and the equipment safe from any flood waters.    I'm sure that West Country builders built the shed square and the dry stone wall is still standing, so blaming camera distortion.     Are you rolling the roof off uphill towards the house, or going for extra long legs on the downhill end and does this affect the warm room?   Hope you get the time and weather to enjoy the build and some clear skies this autumn and winter to sit back and enjoy the views.

3 hours ago, OuterObsession said:

Hey I've been following this project for a while now and think it's really cool. After not having a lot of success with the 28byj-48 stepper motor (too weak) I switched my setup to use a nema 17 stepper motor. Because of the larger motor I now needed to use a different solution to drive the larger motor, I found the easy driver board to be a great solution!

As a result the code isn't compatible with the different board, unlike the 28byj-48 stepper motor which uses a uln2003 to drive the motor you don't have to manually switch between each set of coils to get the thing to turn. The really great thing about the easy driver is you just tell it when to make a step, which direction you want to step in and the resolution of the step. So as we speak I'm in the process of creating a 'B' variant of the 2.5.0 arduino sketch designed to work with drivers that simply take step commands. This will help people out there who are struggling with the arduino stuff who have used something other than the uln2003 to drive their motor. I'll share it when I'm done so people can at least get the sketch from here or tekkydave can add it to the sourceforge if he's still hanging around

Happy imaging and cheers from down under,
~Jameson

Look forward to seeing this and probably will have a look at the Nema17's too!

Worth saying I struggled with 28byj-48 steppers, which was not quite enough to move the OC2 focuser, FW, Barlow and Cam on my OO newt (via 10-30 MX belt reduction).    However, earlier in the thread someone pointed to a 12v version of this motor which has worked brilliantly (even working supporting my DSLR and coma corrector).    Though, if you are directly connecting to the focuser shaft a more powerful stepper like the NEMA17's  is needed.

Well done Steve, a long and difficult path and not for the feint hearted - rather more of a pilgrimage in hair shirt 'n shorts. The end result must be even more satisfying, particularly after a good night's sleep.

Now it just remains to batch and automate the processing :-)

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