Thalestris24

Not sure - maybe a simulator - a 'dummy' version without proper hardware in place

Can you use it without the wifi i.e. just with hanset and cable or computer+ cable?

Hi If power is ok it could be a problem with the handset cable or connector. Did it fail suddenly? When did you last use it? Might the handset cable have been damaged? Louise

That looks good - it's like some strange, ancient artefact! Thanks for posting I'll see how my finances are in the new year... Louise

Hi Jon It kindof depends on what targets you have in mind, what scope/lens you plan to use with it and whether you want a cooled camera or not. They are more expensive but perhaps better in the long run. Having said that, some of the new cmos astro cameras are sensitive enough to be able to do short exposures (lots needed) and if used mostly in the cooler, wintry months will likely give quite good results without cooling. Unfortunately, I don't actually have one but plenty of people on here do! Louise

Hi I don't know the camera/sensor but it has been done and you can buy a ready monofied one from here. However, I don't know if it's really worth the time, effort and risk, of attempting it yourself these days. You can buy cmos mono astro cameras relatively cheaply and cooled versions for a bit more. Having a cooled camera is important for long exposure imaging preferably set point with a good delta. Louise

I see https://twitter.com/dhewlett (Stargate Atlantis) has a Prusa ha ha Louise

I just splashed out £119 on a qhy miniguidescope - aluminium tube, 30mm lens and a bracket. Makes you think! Perhaps buying a 3d printer for, say, £100-150 (or less as above), seems good value even if you have to tinker/fiddle/upgrade. Lets face it, us astro people also like other techy toys to play with on cloudy nights . Well I do, ha ha. Louise

Let us know how it goes! Louise

I can't afford, or justify, ~£600 though. I'll maybe look again next year, if I'm still around, lol. Louise

Me being of Czech descent, perhaps there's something to be said for getting a Prusa! Ha ha. I think I'm only now realising that some I've seen are actually clones and Amazon probably isn't the best place to shop for one! Louise

Hi Julian Thanks. Um, what amount constitutes 'cheap'? What 'decent'? Ta Louise

Hi guys Thanks for all the replies - much appreciated and food for thought! The idea of getting a 3d printer was just one of my late night musings ha ha. I was thinking it would be useful to be able to make my own custom fittings and bits where there apparently isn't anything available commercially. I don't think I'd need to print any single item bigger than say 120 x 120 x 25mm, probably mostly smaller than that. I wonder, though, how rigid printed items might be? I'm imagining plastic = bendy? I've no experience at all of 3d printers or their outputs or their limitations, but I figure they must have some uses! I was thinking I'd be prepared to spend up to ~£300. I just had a quick look on Amazon (as you do) and noticed many are priced at <£200 - would that be considered cheap / too cheap? How much are the consumables? What about cad software? More fundamentally, would a 3d printer be safe to use in a flat?? Thanks again Cheers Louise

Just casually wondering what 3D printers anyone has / would recommend. It's just something at the back of my mind at the mo. Thanks Louise

I bought a Samyang 500mm f6.3 which I tried a few years ago and found ok. It was to potentially use on the SA but balancing was problematic and also the SA tracking was terrible at the time... I still have the lens - it lives in a box in the bedroom ha ha. If I could figure out a way to mount it maybe I could resurrect it to use with the improved SA, but it's not a priority. I suppose I might get more out of it with daytime use or maybe even solar with Baader film. I have the 2x converter which might make it better for solar with a dslr. Mind you, with the near permacloud up here, it's just a dream at the moment! Louise

I could do with something like that for my Samyang 500mm though I don't think there's anything commercially available and I don't have the means to make one. In any case, the collar on mine (such that it is) is only about 4mm wide. Had I realised before I bought it (several years ago), I'd probably have sought out a different brand. Oh well. Maybe I'll get another, one day. Louise

That's pretty good! How many subs/length? How do you balance? Louise

Yes - see above! (Did it post-adjustment at 12x speed -> 2hrs rather than a tedious 24 )

I would say the wedge isn't as good as it could have been. However, it's obviously geared up for short focal lengths since the alt/lat adjustment is very crude and not stable. I've only just got my SA going again after 3 years sitting in a box... I ran it with an 1100d + zoom lens at 135mm last night (with guiding) and it wasn't too bad but I had to reset the guiding every few minutes. When I checked after a while the PA had gone off and you obviously need to have the lat adjusted just right but it always seems to move though maybe it was the user, ha ha. I was guiding at 180mm so in theory there should be a lot of leeway when imaging at only 135mm. I've yet to have a close look at the data (just taking some calib frames). I've learnt not to expect too much from it... Louise

Gave it a quick test last night with a 75-300mm lens set at 75mm. Seemed to give ok 60s images at first sight but close up the stars weren't so good. But I only did a guesstimate PA so that could have been quite out. Today I did a bit of diy and drilled some aluminium bar to fit in place of the counterweight bar. That's allowed me to attach a guidescope so will try that out in the hopefully, not-too-distant future... Louise

Um, does anyone know if it's possible to drift align/darv the SA with just a dslr+lens? Obv can't slew the SA as you normally would to drift align. Polarscope is not an option. No guidescope currently attached. Any thoughts/suggestions? Cheers Louise

I have some electronics knowledge It was a case of having to open it up but, as astro equipment goes, it's not that expensive and it had been gathering dust more or less since I bought it 3 years ago. So nothing to lose! There isn't much of a load on it so not much grease required, I don't think. There's only one bearing which kept it's grease. In normal use it only moves really slowly so I don't think the grease is that important - just a little required. Now I know how to undo it, I could easily go back and add some grease should I ever feel it's necessary. The above 2hr 12x test was fine, so that was encouraging. There are two screws which hold the motor in place. By slackening them off you can move the motor to minimize backlash. As I mentioned, you can only get to the second motor screw by undoing everything. There is a hex nut which slackens off the worm gear and an adjuster next to it. I decided not to adjust the adjuster! I hate worm gear adjustment! There is noticeably less play in the RA axis now. I posted a video showing the play in RA 3 years ago but then just put it to one side... I might, possibly, get a chance to give it a test tonight but I'm not holding my breath on that! Louise

I did a quick Sidereal Day test earlier though I cheated, hee hee. I ran it at the 12x speed which meant it completed one revolution in 2hrs. It was pretty spot on so that was reassuring. Maybe one of these days, in the not-too-distant future I'll get some clear enough skies that will let me test it properly. Fingers crossed! Louise

I think life's too short ha ha

Here is a pic of my SA pcb. Should anyone have any interest, I've figured out what most of the ic's are: U1 is a 1502 programmable logic array - 'the brains' U2 is a 352 optocoupler U3 ? (managed to skip that one... It's probably a linear device to do with the motor control) U4 is a 6552 Motor driver U5 is a LD1117 low dropout voltage regulator - anything slightly over 5V is regulated to 5V which is probably how the nominally 6V batteries last so long! It can supply up to 800mA U6 is a PL2303 Prolific usb-serial bridge controller. Presumably only used for upgrading the firmware in the 1502 So not much to it really My usb/5V input seems to be working now All put back together for (initial) testing Louise