Forum Replies Created
-
Posts
-
Yes. That makes sense. Had wondered about getting an additional USB socket on an Express card. Hadnt thought of the docking station though (I do have one somewhere). Might get a spare docking station while they are still available – I have a feeling the later Dell models also have a connector, but its a different format – will worry about that when I upgrade (I’m a fan of kit thats oldish, so that when it breaks it is not an expensive event – good for the stress levels.).
Will grab a card and let you know how it turns out.
Glad to hear I havent got it completely wrong then. It is very reassuring to hear other people already do this.
I made sure the Dell I am thinking of is W7 rather than XP on because XP doesnt get security upgrades anymore.
Now, if I can just get the garden sorted and the redecoration done and the skirting boards replaced and the paths laid and the…..
This will be fun.
I did try a Dell D630 30ft away from the house in the garden, with a CCD attached and it seemed to work fine when accessed by Remote Desktop and a Wifi connection. It happily sat there taking 5s exposures for me and displaying them. I didnt even need to move my Hub from the other end of the house – I will probably add a repeater when I use it in anger (theres minor issue of putting a pier in, adding the mount/scope and adding an observatory to be overcome yet) or add a couple of ethernet cables to the trunking carrying the mains out there.
I’m not sure why more people are not using Remote Desktop. What dumb error am I making? Security? 🙂
A key fob on the roll off roof is pretty cool 🙂
Will indeed look out for well protected cables. We have foxes round here certainly – the footprints in the recent snow were really obvious. Other things too – though pheasants, deer and voles are not normally a problem for telescopes, but rather unwelcome in the nearby veg patch.
I noticed several people mentioned the software they use to access the instruments in the observatory from indoors. Sounds like there are several good options out there – and some of them free to private non-commercial users. Its nice to have multiple good choices. I’m rather favouring using Dell D630 laptop outside as they have 4x real USB sockets and are rather cheaper than decent spec NUCs – t he NUC may come later (its compactness is attractive). Dell D630s are certainly not the fastest machines in the world but good enough to run an autoguider and CCD at the same time.
Thanks for the comprehensive reply.
Fortunately, I am not going for a fully automated solution. In the absence of a shed that lends itself to automation I don’t think its worth the hassle for me just to avoid going outside in the dark/cold for 10 minutes at the start and the end of each session. Can see the joy and challenge in it though.
In light of what seems to be the opinion of USB over internet, I will probably go for a NUC hung on the back of the scope so all I need a is 5A 19V power supply cable and an ethernet cable connecting to them to Remote Assist/desktop via.
A thermostat/heater on the NUCs will be needed of course as few computer drives are good for operation sub-zero.
Still means trench digging of course, but theres no way round that without recourse to batteries and a big solar panel on the shed roof.
Shame no one in the UK manufactures motorised run off roof sheds that can be run from a PC. Theres a market niche.
Perhaps if my DIY To Do List was <1 sheet of A4 (8 point font). 🙂
Thanks again. Have you published any accounts of your observatory?
So the Pi handles the USB control locally (and presumably provides buffering) and then squirts it across the network as loading permits? Thats sounds fun and worth trying out. Four Pis are hardly expensive – I recall that in the earlier models Pis were internally a single USB port so I would probably need at least 3 if I use two imagers.
Thanks.
Thanks for that. The only colleague I could find who had used one much in anger was merely feeding keyboard and mice down one Cat5. Unsurprisingly, he didnt have much problem.
Thats an interesting presentation. Am I reading that right? The 1pps pulse goes straight into what appears to be an Arduino GPIO – should work!
Yes, the slow speed (4800 or 9600) of the serial comms links many receivers use worried me and I know that several that are ostensibly USB actually use a USB/Serial interface internally and so are just as bad. I noticed that to get round this the NMEATIME2 shareware uses a Kalman filter to filter NMEA arrival times and manages to get an accuracy down into the single milliseconds.
I’m told – would have to check old emails for detail – that the 1pps is very accurate long term (so count 100 pulses and the average interpulse time will average very close to 1000ms) but the individual arrival time of a pulse is still somewhat dithered – on some hardware.
Can dig out the emails if you are interested.
So, on eclipse day you were in a jeep too Martin. We were in the back of a jeep driven by the operator of the 88″. Woke to pouring rain and no hope, but the guy – who could have gone to the top of Mauna Kea (being observatory staff and able to get past the police cordon) if he hadnt stuck with us – went to the saddle road and waited.
Managed to see it through fog – so stuff all corona apart from prominences but binoculars showed the structure in the inner corona despite the fog. No Cat Stevens (happily) but there was a burst of Robert Plant’s Manic Nirvana before we left base in Hilo that morning.
Just an update: I have been out with the RASA on two nights so far – 11th and 13th – and not yet had trouble with dew forming on the corrector plate – even in the absence of a shield. Hiwever, neither was a wet night (it was -1C and -5C respectively) but there were hard frosts (really hard last night). Will update again when I have used it on a night when water is running off the mount or pier.
A friend has tried a Canon 450 on it but nothing bigger yet. The Starlight 56 has too big a body – the issue being the shutter. The Starlight 25 would be a nice start or better still a 35. However, I don’t have access to anything bigger and so cannot oblige. Anyone want to lend me one? 🙂
I think Celestron have said that wings of the focal plane should run off to 60-70% of peak. The 14″ version is better controlled and is corrected better for wavelengths beyond 800nm.
Finally got some quality time with the Celestron 11″ RASA. The attached image is M81 and M82 – though I rather suspect you all knew that. I used a venerable Starlight H18 for 15 unguided 60s frames last night. The focus was a little off – my fault not the scope – and also the camera body is not properly aligned with the focal plane after some changes made to ensure it worked with a Canon lens adaptor. So, this pretty much suggests that someone doing the job properly will get quite a nice result.
I liked the focuser, the quality of the images and the speed of the system, but it has made it very clear I need to sort out the cable mess I have before I go much further. I’m not used to wires coming of the scope front – not after using a RC for a while.
I tried deleting one of the images but lost both, so two it is…
