Astrosurf Posted September 14, 2011 Share Posted September 14, 2011 I never seem to be able to get my scope to track well, even with a successful 3-star align and objects being dead centre. I know I should ensure my mount is level, which I don't but thought about getting into autoguiding now I've managed to get going with astrophotography.Can anyone advise on the cheapest set-up: guide scope, sw etc?Alexxx Link to comment Share on other sites More sharing options...
Kai Posted September 14, 2011 Share Posted September 14, 2011 You are still going to need to make sure your mount is level and correctly polar aligned to get the best out of any type of imaging , guiding will not cure this.Why not spend some time setting your mount up and see how long your subs increase , you dont say what scope / mount combination you have but i would of thought 60-90 secs are achievable unless you are imaging at a long focal length. Link to comment Share on other sites More sharing options...
Spikey Posted September 14, 2011 Share Posted September 14, 2011 Hi Alex, I hope that means the handset is working well I would echo Kai's comments, with a good setup I can easily achieve 3 min+ subs unguided. Equally when I've made a mistake or rushed soemthing I can't even get past 30 seconds without the sub lookng terrible.What mount /scope combination are you using at the moment? Link to comment Share on other sites More sharing options...
Astrosurf Posted September 14, 2011 Author Share Posted September 14, 2011 Yes, the handset's working well now, apart from seizing up at one point, so thank you!I have a Skywatcher 200P on an HEQ5 mount. I polar align using the reticule and setting circles (from Astrobaby's turorial) and which seems to work (calibrated reticule, set Polaris transit etc, etc). I would have thought that the 3-star align would be out if my polar alighnment was out? So, apart from a non-level scope, what could I be doing wrong?? Link to comment Share on other sites More sharing options...
Kai Posted September 14, 2011 Share Posted September 14, 2011 Have you calibrated the Polarscope ? , if you have then all i ever did was to use Polarfinder and place Polaris in the small round circle.Next time you are out forget about the Handset alignment, just have it running , level the scope , set Polaris and point the scope to the East or the West at about 45 degrees and take some images and see how you go from there. Link to comment Share on other sites More sharing options...
Astrosurf Posted September 14, 2011 Author Share Posted September 14, 2011 Yep, calibrated the polarscope. I'll have a go at levelling the mount next time. It's a shame I didn't get hold of one of those spirit level attachments that FLO were selling. I don't think they can get them any more! Link to comment Share on other sites More sharing options...
Merlin66 Posted September 14, 2011 Share Posted September 14, 2011 The mount doesn't need to be level to do its job.....all it needs is the polar axis to be aligned to the pole - that's it.KISS (Keep it Simple, Sunshine) Link to comment Share on other sites More sharing options...
Astrosurf Posted September 14, 2011 Author Share Posted September 14, 2011 But I've done all that and it still doesn't track perfectly. Link to comment Share on other sites More sharing options...
Merlin66 Posted September 14, 2011 Share Posted September 14, 2011 That's where the auto guiding comes in...the mount may be pretty well aligned but the accuracy of the drives - variations in the gears etc etc can cause the tracking to be less than accurate. The idea of autoguiding is to "lock on" to a star and hold it perfectly in place (within a fraction of a pixel) - this is done by measuring the error (very slight movement of the star image) and issuing a correction signal to the drive electronics to move the star back to position - before the movement even becomes noticable in the image .....white mans majic.Seriously, if our mounts tracked well, we wouldn't need to go to all this hassle about autoguiding....such is life. Link to comment Share on other sites More sharing options...
jaffons Posted September 18, 2011 Share Posted September 18, 2011 Im also starting this hobby and asking Q's:If mount is autoguided, how much different mounts have difference in accuracy? For example EG3..EG6..Losmandy ect..What kind of focal lenght and quality is needed for guiding scope?And as the OP asked: Can anyone advise on the cheapest set-up: guide scope, sw etc? I have also skyliner 1200/200mm(f6)How long subs can one have without guiding, if using shorter focals (85mm..300mm)? Link to comment Share on other sites More sharing options...
ollypenrice Posted September 18, 2011 Share Posted September 18, 2011 To ditto Ken, you do not, in fact, have to have a level mount, just a polar aligned one. The very accurate Takahashi mounts don't even have adjustable legs. Don't confuse pointing accuracy with tracking accuracy. They are not connected.The difference between mounts in terms of tracking accuracy (lack of periodic error) is enormous and closely related to price. Premium mounts run at a couple of arcseconds of error while budget mounts like the NEQ6 run more like 20 or more arcseconds. But now for the good news; mounts like the NEQ6 autoguide out very well and, unless you are using a long focal length, will allow you to get excellent results. Just get into autoguiding! I can't help on the cheapest option because I see it as the most important part of the setup and don't skimp on it. But an ST80 with QHY5 seems to deliver the goods for lots of SGL members, running in the free PHD software.Olly Link to comment Share on other sites More sharing options...
x6gas Posted September 18, 2011 Share Posted September 18, 2011 I have a Synguider running on a Skywatcher ST 80. ST80 bought second hand including guiderings and total cost ~300 quid. Not a bad, very portable guiding solution IMHO.HTH, Ian Link to comment Share on other sites More sharing options...
malc-c Posted September 19, 2011 Share Posted September 19, 2011 There's some debate over using an 8 x 50 SW finder as a guider with a standard web cam and adapter from Modern Astronomy. I was going down that route the week an HEQ5 / ST80 / QHT5 came up for grabs on the FS section. If money is tight then for £60 - £70 for the adapter and camera it would give you a means of auto guiding without hitting your bank balance too hard Link to comment Share on other sites More sharing options...
jaffons Posted September 19, 2011 Share Posted September 19, 2011 So I have this lying around, and I wonder can I make it autoguider with any cheap cmos webcam? I dont like Idea about 200e guider camera.. Link to comment Share on other sites More sharing options...
Whippy Posted September 20, 2011 Share Posted September 20, 2011 There's some debate over using an 8 x 50 SW finder as a guider with a standard web cam and adapter from Modern AstronomyThe problem with webcams is that unless you're planning to do the long exposure mod, they simply don't expose for long enough to grab only but the brightest of stars. Time you add in the cost/time for the mod, plus either a guideport box or go the EQMOD route buying the necessary lead, then you might as well get a proper guidecam with a ST4 port. IMO, spend a little more and make it hassle free. Get a specific guide camera like the QHY5, a small cheap refractor and a side by side bar. Install PHD on your imaging computer and off you go. In the 3-odd years I used that setup, it never failed .Tony.. Link to comment Share on other sites More sharing options...
Astrosurf Posted September 20, 2011 Author Share Posted September 20, 2011 I don't really understand all this! Can anyone post a pic of your setup and what you use, even a link to some equipment? That is, guide scope, software etc, and please assume I'm a complete numpty! Well, I am! Link to comment Share on other sites More sharing options...
Kai Posted September 20, 2011 Share Posted September 20, 2011 Alex please dont take this the wrong way but names , pictures and links will get you even more confused than you are now.Why not spend some practical time with somebody at a Star Party for example and see the equipment / process they go through , you will learn faster and actually get a "feel" for what you need and if its the right thing for you.Im sure one of the seasoned imagers wouldnt mind Link to comment Share on other sites More sharing options...
appalachik Posted September 20, 2011 Share Posted September 20, 2011 Hi Alex, QHY5 / PhD autoguiding works fine for me... I just use an 8X50 Celestron finder, eyepiece removed and QHY5 screwed via an adapter I got from Modern Astronomy. In fact, it was Bernard at Modern Astronomy who suggested this setup to me. The whole lot is on my main tube assembly, attached with a TS Optics SuHa50 mount. I get very acceptable results from a relatively inexpensive and simple setup. Nothing fancy, like Merlin66 said... KISSJenna Link to comment Share on other sites More sharing options...
malc-c Posted September 20, 2011 Share Posted September 20, 2011 Alex,Hope this helps, but I have to agree, if you can find someone local who can help show you the settings etc. Doing it on your own is a steep learning curve, as I'm finding out.Anyway, if you want to convert your SW finder and connect a web cam or preferably a QHY5 then you'll need a T mount adapter like thisThis replaced the eyepiece and allows the connection of the camera like thisI would have to agree, you will be better off using a QHY5 for guiding than a web cam, but the suggestion was more for information only... it (as pointed out) has drawbacks as it lack the exposures to pick out fainter stars.The alternative "standard" seems to be the SW ST80 with an QHY5 camera, often piggybacked on top of the main scope, or using brackets and dovetails, along side it. There are lots of examples of this - best place would be to look in the thread of "show us your equipment" that's currently running.PHD seems to be the defacto freeware program to handle the guiding, and preferred use is with EQMOD to control the scope. The QHY5 also has a ST4 port so if you control the scope via the handset you can plug the camera directly into the handset / mount if you don't use a laptop Link to comment Share on other sites More sharing options...
Astrosurf Posted September 20, 2011 Author Share Posted September 20, 2011 Thanks guys. I do think a demo will be needed. Mind you, I really don't have the money for a guide camera. I was hoping that my Phillips webcam would be suitable but obviously not. I'll just have to get used to sub-standard pics for the time being. Very frustrating! Link to comment Share on other sites More sharing options...
malc-c Posted September 20, 2011 Share Posted September 20, 2011 Alex, for £29, the cost of an adapter from Modern Astronomy to connect the Phillips webcam, you could always give it a go. If it works out within the limitations of the exposures then all well and good. If you find that you need to point it at a very bright star to make it practical, then look modding the webcam for long exposures. However, it's worth considering purchasing secondhand. Average price for a secondhand QHY5 is £110... that's only a little more than the cost of a pre-modded long exposure webcam (typically £90 off e-bay) Link to comment Share on other sites More sharing options...
RogerTheDodger Posted September 20, 2011 Share Posted September 20, 2011 BTW, I have found a bug in PHD when used with an LX webcam, Craig Stark has provided me with a fixed version this morning which seems to work, but obviously I haven't had a chance to evaluate it outside yet. I'll post a thread with the details later. Link to comment Share on other sites More sharing options...
Astrosurf Posted September 23, 2011 Author Share Posted September 23, 2011 Thanks guys. When I can justify the dosh I'll look into this. Link to comment Share on other sites More sharing options...
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