Thalestris24

Yeah, I'm intending to print somebody else's design of a diy astro spectrometer so it would be probably be opening a can of worms were I to attempt to change any dimensions. It's only quite small (of the order of about 100mm on a side, and maybe 70mm deep) - mostly a shaped box/enclosure and fittings for the optical components with telescope and camera interfaces. As long as it stays stiff enough it'll be ok but might end up just being a prototype... Louise

BTW has anyone tried carbon fibre or other reinforced pla? Just curious, really, but also thinking ahead to a possible MkII version. The Lowspec spectrometer is going to be reliant on the stiffness of the parts. Ideally, it should be made of metal but that's not going to happen! I may be overthinking again ha ha. Louise

Yes, that's the one! I've started getting the parts in Creality uk are a bit ambiguous - it says 'out of stock' but with a green tick next to it - hmm... As you say, there are other sellers though I've read you need to buy from Creality to get their support, should one need it. It may not be a big deal in reality. Anyway, I've contacted them to check their stock situation. Louise

I'm probably overthinking things - I do that! The designer of the Lowspec spectrometer (which is one thing I want to build) used pla so it must be ok for prototyping, at least. Maybe I could also spray paint or otherwise coat the printed parts to improve durability. Creality UK seem to be out of stock with the Ender 3 Pro at the moment though Amazon appears to have them. Louise

Have seen all those, thanks! Louise

The Ender 3 Pro does look quite good. I'm a bit concerned about the durability and stiffness of things I might print though. Apparently, PLA, though environmentally friendly, does tend to break down over time. That really only leaves ABS which I know isn't so stiff? I need stiffness and durability for astro parts/stuff. I've read about PETG but maybe the Ender 3 can't cope with the higher temperatures needed? Any thoughts? Thanks Louise Any thoughts?

Yeah, I've figured all that out now Louise

I've been reading through all the relevant Shelyak product user guides and feel I have a better understanding of how slit spectroscopes work on a telescope now One of those Lhires III instruments would be nice to have... Oh, previously I hadn't initially twigged that the Lowspec was essentially the same as the commercial instruments - d'uh. Louise

Yes, I've seen that and downloaded it all,, thanks Louise

That helps a bit, I think. Hopefully your book will be useful too Am I right in thinking that, once everything is properly aligned, it's the reflection of the (Ovio) slit in a mirror that enables locating the target star via the guide cam? Being a total slit newbie means those details aren't so clear to me, though must be second nature to you! Cheers Louise

I have all the files but there doesn't seem to be anything that describes theory of operation or how to use. I suppose just have to figure it out... Thanks Louise

I may be having a senior moment, or it's just that I have a rotten cold , but I've not been able to locate an overview of the Lowspec design. I'f downloaded all the files from thingiverse but couldn't see any actual design document. Ditto the forum. Anyone have a link? Louise

I was thinking of the cost of the Alpy guide module price - Euros 855.60 😮I'll have a deeper look into the LowSpec - have downloaded the files. Louise

Thanks, Robin. I see the difficulty... The mirror slit is probably something you can't make yourself - hence its expense . I might just only build a bench spectrometer and leave it at that. Perhaps a beam splitter could be a workaround, accepting a loss of transmitted light. Oh well. Louise

Cool - and, thanks!

Hiya Ahhh - the Merlin Spectrometer! Are you by any chance the author of https://www.amazon.co.uk/gp/product/1441972382/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 ? I just ordered a copy Have you ever built a uvex? Louise

Mirror slit guider? Ah, I think this explains it

Ta for the info, Robin! I think this astro spectroscopy has given me bipolar disorder - I'm blowing hot and cold over it! Can I ask why the system would be unusable without the guiding module? Wouldn't a standard oag work instead - or even a normal guider? I'd still only be doing brighter stars - if I actually do get around to it... Louise

I think the optics part of this even simpler Czerny-Turner could easily be built first, as a stepping stone There's no need for the RPi control/electronics stuff! http://2018.igem.org/Team:Aachen/Hardware Louise

I guess not! I've been through Christian Buil's documents and had a peak in the spectro-aras.com forum. With the right setup this Czerny-Turner slit spectrometer looks to give very good results. The incorporation of a cylindrical correction lens appears to make all the difference. I'm thinking it could still work ok with my equipment (fracs) and the cost of the components isn't that high compared to commercial spectrometers. It does need a 3D printer to fabricate the casing etc. but I'm looking at getting one of those anyway. The hard part seems to be the optical adjustment which needs to be precise. Plastic will always suffer from flex and a version machined in Al/alloy would be a lot better, but beggars can't be choosers! Christian has designed it to reach well into the UV part of the spectrum and with the ability to switch between the wavelength ranges of interest i.e. toward UV or toward IR. Since my telescope equipment isn't anywhere near up to his gear's capabilities, I figure a 'downgraded' version of the UVEX3 could still be built with maybe a lower specification, or lower expectations (or both!) but still be better than a Star Analyser. He has tried the UVEX3 with a short frac and still got ok-ish results albeit at a much reduced resolution, I think. There will always be limitations due to imprecise colour correction of a lens-based scope. And, living in Glasgow, the wet atmosphere, turbulence and light pollution won't help my efforts at all! Anyhow, here are links to the design and construction info: https://www.shelyak.com/wp-content/uploads/SMSW2_Buil_UVEX.pdf http://www.astrosurf.com/buil/UVEX_project_us/ I might have a go at building a simpler 'bench' version without the complications of interfacing to a telescope. It's a diy project but not a trivial one! Not sure when I'll be able to find the time (I'm doing an evening class at the moment which generates lots of homework and assignments but the Christmas break isn't so far off. If I get a 3d printer now and can get my head around it, then I might be in a position to have a go at the UVEX3 over Xmas. ) Still, if anyone else wants to have a go, the optical components are easily available from Thorlabs. He gives the part numbers in the pdf. Louise

Hi Nigella The RSpec video tutorials are very good and I imagine the BASS software isn't vastly different. Same principles anyway. I joined the Astrobodger forum last night but haven't yet downloaded the BASS software but will do soon. Here's a link to the videos on youtube: Workshop: RSpec link: https://www.rspec-astro.com/more-videos/ Good luck! Louise

Gosh, it's just over a year since I started this thread! I never did get around to buying a 3D printer kit... But... but... Now I think I really do want to get one Is the Ender 3 Pro still a reasonable starter? It's going for around £220 at the mo which seems affordable. I just want to print smallish things mostly linked to astro stuff, maybe no more than about 12cm square by maybe 8cm high. Until I get one of these things I will know nothing, and have no feel for the ins and outs of 3d printing, so have to just dive in! Any thoughts or other make suggestions? Cheers Louise

Anybody built and used a UVEX(3)? Also, ditto the same but with a Schmidt correcting plate/optics? (A bit niche that, I know! ) Louise

I have a qhy183m (cooled) and I love it! It has a high qe and is fast (via usb3) and excellent for live stacking using the Ascom driver in SharpCap Pro. It's low noise even at full-well and you only have to cool it to -10 deg. It's very versatile as you can use binning as well as ROI. It's my fav camera these days! I also use the qhy5l-ii mono for guiding on some setups - never had a problem with it. Louise

The specs don't claim the tec will work reliably at 100% - as above, operation becomes unstable >90%. The spec only claims a delta of 35-40 deg below ambient within the given environmental limits. Louise