SteveNickolls

Hi and thanks for posting. I'm really hoping that despite the number of these (and other organisation's) satellites that are due to go up into LEO the stacking software will remove them. My own interest is with wide field imaging so more satellites are to be expected in individual exposures. I have put a temporary hold on buying new gear to see how things go this season. In the UK we only get a relatively small number of clear night's for imaging, in the three years I've been imaging this has varied between 30 and 44 occasions each year. When a future cargo launch of satellites is launched we are likely to endure the initial train of satellites which if this coincides with a clear night has the chance to scupper that evening's work. This year Space X are meant to be launching 5 more of these satellite groups and have up to 12,000 satellites to place, that could mean 200 launches. I understood the craft have a lifespan of 5 years so to keep numbers of the constellation up continual launches will take place. This is just for Space X. I don't envisage changing my sport to imaging satellite trains. Time of course will tell. Best regards, Steve

Yes, just taken a couple for you- Fitting the adapter was a little fiddly, getting it sitting as flush as possible while tightening up the little internal grub screw was perhaps the most awkward part. I don't think I'll be removing the adaptor often if I can avoid it. The other thing I'll alter is to replace the very tight fitting top cap with a little plastic bag and elastic band. I also found I had to take off the mount's DEC clutch lever and re-position so it can be tightened with the iPolar in place. Cheers, Steve

Well I've bitten the bullet and a day after ordering (thanks FLO) have my iPolar fitted into the top of my CG-5 mount's polar opening. The camera is recognised in Win 10 (64-bit) and the iPolar software has been installed on the laptop. Just need the cooperation of the fickle weather now to give it all a try out and to post comments. 😀 Cheers, Steve

I certainly would, you may find it needs no change from the factory. Enjoy the mount. Cheers, Steve

I really wish that Sharpcap will be able to extend its functionality to DSLR's but am haunted by the knowing comment, "let's see how far it gets" here-https://www.otelescope.com/forums/topic/2821-bye-3rd-party-api-used-as-basis-for-ascomdslr-driver/ Cheers, Steve

Sorry to hear this if I'd known performance could vary so much I'm not sure I'd have committed to getting one. I'm aware there are a number of different maker alternatives out there on the market for this caliber of mount. Best Regards, Steve

Hi Fabio, Sorry to hear your experience with the SA has not been so good. I have only just recently been working to bring my old CG-5 Go-To mount back into use and learning how to use PHD2 and decipher its graph to check how the mount is performing. I've not thought it necessary to use it on the SA so no idea what its PE etc are like. Are you using a PoleMaster accessory to obtain your alignment on the SA mount? I have been very pleased with how the SA tracks finding the supplied polar scope so much better than the old Celestron types. It didn't need any adjustment from the factory when checking the polar scope was aligned in the mount. As I mentioned in an earlier post I did find the SA wedge quite poor so it's very likely that quality varies with each part of the assembly, luckily I replaced the wedge for an old Celestron Alt-Az mount/tripod I had lying around which is so much smoother to operate for polar alignment and probably more sturdy than a photographic tripod. I didn't mention before but a house brick (about 3kg) is placed on the eyepiece tray to keep everything steady. Regarding subs at 135mm yes my standard exposure length is 300 seconds and unguided the only time I had an issue was when I had not balanced the set up properly to image at a high elevation and found a few slipped frames. Most of my imaging is relatively wide field with the Samyang 135mm lens at around 6 x 10 degrees but good for making mosaics. Here's a 4-pane mosaic of part of Cygnus from last October each pane was made from between 18-24 300 second light frames with matching dark frames from my library and master bias and flat frames, I've used StarTools to turn it into an inverted image so you can see the stars better, the Samyang gives good star shapes- As I've been busy on the few decent nights this season making mosaics I've not used my 75-300 mm lens much to follow consistently up on the 150 and 180 second exposures performance but may next season give this lens more of a try. After imaging at f/2 using the stock zoom at around f/6 is so ponderous. Again I'm sorry to hear you have had less fortune with your SA mount. Just a thought, is it still under warranty to return it to the retailer? Best regards, Steve

Hi, and thanks for posting. I’ve had my Star Adventurer (SA) mount since April 2017 and found it a lovely piece of equipment for taking wide field images. Used within its operational capabilities it works extremely well, the tendency is to push too long a FL optic or payload weight onto it. You will need to factor in a suitable, rigid tripod to hold the SA and your experience with the SA’s wedge will vary. Mine was very stiff to use and coarse so I did away with it and used an old Celestron heavy duty Alt-Az mount which is way smoother when polar aligning. Your experience will of course vary. The large clutch on the SA can get over tightened but Sky Watcher produced this video to help rectify the matter- You soon get to judge what tightness is needed on the clutch and how to do things in the dark! When polar aligning the SA’s polar scope is very decent and if you employ the SkyWatcher Star Adventurer Mini App you can use the polar clock capability to accurately set Polaris. My advice would be to finish polar alignment when Polaris is at either a major division (eg 0, 10, 20, 30 ,40 ,50 minutes) or at the half way point (5, 15 etc.). This accuracy can make the difference when using longer FL lenses. I was able to increase the exposure time at 300 mm FL from 150 to 180 seconds using this technique. The polar illuminator that comes with the SA is annoying and has a tendency to drop off until you use some tape to secure it. Using the SA you come to the point wondering what sub-exposure length to adopt as with short FL lenses you find you can track for ages. There’s a law of diminishing returns as far as exposure time goes, especially if your location is controlled by local light pollution. With shorter FL lenses such as 135 mm I’ve been quite able to obtain exposures of 15 minutes but depending on the light pollution where you image a much shorter exposure time may suffice. Here the speed of your optics will come into play. I generally use a 135 mm Samyang f/2 lens with a clip-in Astronomik 12nm Ha filter and find 300 seconds an optimum exposure time, I have done longer but 300 second sub-exposures do the job and now a spoilt frame due to cloud only loses 5 minutes of the session. The 300 seconds sub-exposure time came partly out of extensive imaging and using the histogram in BYEOS to best judge what I considered was an optimum exposure time, it comes out pretty close to what is explained and calculated in the presentation below. You might find this sky fog calculator useful- http://tools.sharpcap.co.uk/ with it you can determine the amount of light pollution at your imaging site and employ the value to provide a value for your optimum sub-exposure duration depending on your optics, local light pollution level, type of camera (colour/monochrome) and any filter you are using. This presentation is very rewarding on the matter of what sub-exposure lengths to try and well worth watching all the way through- You could skip the very interesting presentation and go to 49.12 in the video where the formula for calculating your Optimum sub-exposure time is given. Provided you know the read noise of your DSLR, how much sky glow you have and how much extra noise you can tolerate in the image you can quickly work out your sub-exposure length. For my set up the sub-exposure time calculates to 312 seconds if I accept a 3% added noise so close to my 'suck it and see 300 seconds actually used. I hope this all helps, I’m sure you will really enjoy the SA mount and look forward to seeing your posts on SGL in the future. Best Regards, Steve

Hi, and thanks for posting. My experience with longer FL lenses (Canon) with the SA mount is that at 300mm FL expect up to 3 minutes sub-exposures if you get polar alignment and payload balance right. That was with a fairly light 75-300 mm zoom lens and which together with a Canon 600D weighed in at 1,164g (2.57lbs). The lens was simply connected to the camera with no additional support. Mostly however I use shorter, faster FL optics on my SA to provide long enough exposures for my imaging conditions in a Mag 5.0 sky. Good luck coming up with your decision and don't forget to post your successes on SGL. Best Regards, Steve.

Thanks, The Samyang lens is reviewed here-https://www.lenstip.com/index.html?test=obiektywu&test_ob=442 I can only add I have been extremely happy with mine which I always use at f/2 with a modified Canon 700D. I'm sure other SGL-ers with the lens will similarly vouch for it. The RedCat 51 has a lot of positive, desirable features but the speed of the optics (from my point of view) isn't one of them. If you bought the Samyang lens (it retails around £440 new) I don't think you would be disappointed. ? Cheers, Steve

+1 to all that. However it's 51mm objective and f/4.9 optics light grasp pales against the Samyang 135mm f/2 lens. Apples and pears though. Cheers, Steve

No, sorry but rather wish I had to prove the value of using an Alt-Az mount. Do post your successes. Best Regards, Steve

Do they export? Cheers, Steve

Thanks noah4x4, yes I've learnt such a lot with my DSLR's and part of me feels they still have a lot left to give so I'm not really in a desperate hurry to spend what is rather hard earned money and prepared to sit out some CMOS developments. The only caveat is I'm not getting any younger of course ? but am prepared to wait. My original idea of adding guiding to the existing gear was that I could become familiar with guiding hardware and techniques and au fait with the software, all things that would eventually be useful with a future dedicated astro-camera. Using a remote mini pc would be the icing on the cake and reduce the number of cables across the garden. Cheers, Steve

Thanks for the vote of confidence over the mini pc ? I really do hope so. Worth keeping those £ in the pocket ready for future use at the right moment. Cheers, Steve

Thanks Noah4x4 and Graeme, you have made very helpful, valid points which will make my decisions easier. My laptop is quite a high spec one with an i7 processor and the concept of trying things out with the laptop and guider first is excellent. I'm reassured Graeme over the mini pc's capabilities in terms of what programmes it can comfortably run with. So to get the terminology right in my head, the mini pc will be the host and the laptop indoors the client? The mini pc comes with Win 10 Pro installed. ? Thanks everyone for this help, it is very much appreciated by me and may serve to help others on this route. Cheers, Steve

My initial intention was to get something such as this-https://www.amazon.co.uk/dp/B0749J27Y2?tag=stargloung-21 so very low power. I would (at least for sometime) be only using it to run BYEOS (for my current imaging cameras), and PHD for the guide camera. I would not be looking to automate focus control, use a filter wheel or plate solve), so quite basic. My initial thought was to control the mini pc at the imaging location down the garden (around 20 metres) using a crossover LAN cable but was not sure of the practicality. The mini pc sited on the mount would connect to the DSLR by a short USB connection and use the mount and guide camera's ST-4 ports (initially) to control guiding. My mount (a CG-5) is run off a battery and the DSLR is usually powered by a dumb battery connected to the mains supply. However if things prove too complex as it is all sounding I might just go ahead initially without a mini pc etc. etc. and simply use another USB cable to control guiding using my laptop (Win 10 Home) in the kitchen. Regards, Steve

I certainly intend following that advice. Cheers, steve