Robculm

Hi Mark, I don't have one since the latest collimation attempt, but here's how they usually look from my previous flats: There's definitely a 'flat' on the bottom. Is that normal, or it should look more symmetrical?

Coming back to this topic & looking for some advice please. So I bought a different mask, RVO's 'advanced' mask which gives me a kind of 6 axis pattern, but I still see the problem, different orientations / axis give different focus! Here's what I see with the standard Bahtiniv (easier to see from the standard mask): I've spent quite some time going through the collimation. Bought & used a 'long' Cheshire, rather than my usual laser collimator. Secondary nice & circular filling the eyepiece & all circles / dots aligned etc. Managed to get a few test sessions in past few days (nice clear skies of course now that the moon is up!). Still seeing this problem & I'm stuggling to get really accurate focus in my images. So I tried 'defocussing' on a star to look at the ring patters: The circles look reasonably concentric to me. They aren't as clear in the photo as they were visually! Sorry. I am a little confused about the two features (left side & top right corner). One of them seems to be the focus tube (top right I think), but not sure about the other!? There's definitely something not quite right though. As I come out from the focus point, the star loses shape on one side: And at focus point looks something like this: Any thoughts / suggestions please (aside from buying a refractor!)?! Cheers, Rob

Finally got a few hours of clear skies to experiment on this a little & not convinced it's the collimation. I've spent some time checking the collimation. Stars are all of equivalent focus across the field of view & this 'effect' of a difference between 0 deg & 90deg of the bahtinov mask is evident when positioning the star I'm focussing on in any position in that field of view... So maybe it is indeed the mask that's a bit crap! Does anyone have any recommendation for good (but not stupidly expensive) bahtinov masks available in the UK? There are certainly some interesting ones in the link (like 'gold astro'), but can't see those available in the UK... Cheers, Rob

Hi Richard, Thanks for your comments. In terms of power, I've now sorted a mains to 12VDC supply. I didn't realise there was this focussing option in the main camera menu, I thought the APP focussing features were all associated with auto focus, so since I don't have one of those I kind of ignored the whole topic & carried on doing it on the camera... I will give that a try, both the 'dedicated' focus & the preview with my Bahtinov mask. To be honest I've still not had a lot of 'live' time with the AAP as the weather has been rubbish recently. As soon as we get some clear nights will get on to this... Cheers, Rob

I have the Sky-Watcher / Celestron PowerTank 7Ah & have found that adding the Asiair Pro drains the battery very fast. I was previously able to run maybe 6h just powering the HEQ5pro mount, but now only 2 - 3 hours. So wouldn't recommend it! I've just ordered a mains power supply as I'm not using remotely for the time being...

I've only had the Asiair Pro a few weeks, but so far I'm well impressed. Works great with my Heq5 pro, asi120 mini & canon 800d. Wifi is well known to be poor, you need to consider how you will handle that. I have been using with my usual skywatcher power pack running the mount, but drains the battery really fast, so needs a good power supply to do that, or separate, or mains... As I said though, overall I think it's fantastic.

Yes, I did install Sirilic at the weekend and had a try, but not quite there yet, ended up with crazy coloured patterns all over the image! However, while I was reading on this topic I discovered that you can download additional Siril scripts, including OSC preprocessing without Dark https://free-astro.org/index.php?title=Siril:scripts 😁

Thanks Mark, that's a very good suggestion. 👍 Will check the collimation & explore this while the moon is back but the nights are clear! (after I've recovered from the 3 sleep deprived nights of trying to image M16 this week!). I find that collimation is somewhat underrated! There are lots of youtube vids which show how fast you can collimate a Newtonian, but rarely do they highlight the importance of getting the secondary mirror aligned! If you're not careful you can easily end up with great alignment of the primary to a badly aligned secondary! 😖 Thanks again, Rob

Quick question / wondering if anyone else has had this problem... If I set focus with the mask rotation giving a 'horizontal' pattern, but then rotate the mask so the pattern is vertical, I'm then slightly off (i.e. no longer passing exactly through the center). At the moment I'm basically just fixing focus somewhere in between, so it's closest to central for both orientations. We're not talking a huge difference, but it's definitely noticeable & it's always nice to know you're exactly focussed before spending hours imaging...! Wonder if maybe it's a problem with the mask? I'm using the 200mm versions of this one: https://www.ebay.co.uk/itm/373432397287 Cheers, Rob

Just to add my short review of the ASIair Pro now that I've got it set up & finally had some clear nights... Overall - Fantastic, really love it! OK, so for sure the bar was set pretty low as I was basically coming from un-guided & using the Synscan controller! Yes, the WiFi is 'challenging'! But I've managed to get it operating on station mode with my existing wifi extender relocated to the window sill! (indoors). Couldn't get on with driving it through the hand controller, so got the EQDIR cable which works great, Synscan is now well & truly consigned to the 'spares' box! Polar alignment works great. Locating objects is now a breeze & the framing of them / actually be able to see your image there & then is amazing! Gone are the days of taking out the camera SD card, running inside to check it on the computer, back out & trying to guess which direction & how far to move... Guiding is great (sure I guess that's the same whatever 'platform' you're using, but coming from unguided, brilliant, no more filtering through the images & throwing half of them in the bin!). Seems to work great with the Canon 800D DSLR... Being able to monitor what's going on while back indoors with the pad is great (although have had a few occasions with the wifi dropping!)... Only negatives so far are that I'm running it together with the mount from my battery pack & it sure drains power a lot faster, but that's easily solved - Lynx Astro power supply is in the mail! And struggling with the live view (i.e. unable to use it when I focus (Bahtinov mask), so having to focus on the DSLR screen), would be nice to get a larger image! So very happy & looking forward to the longer / darker nights... 😀

Thanks HTH, I have started dithering now that I have the guiding capability (ASIair pro seems to be working a treat in that regard), so will definitely give this a try. Only problem is, it's brings me back to the problem that without darks, the OSC_Preprocessing option in Siril won't run, so as you've mentioned several times, I'm going to have to learn to use it 'manually'!!! 😆 Cheers, Rob

So here's the comparison. 1st without UHC, 2nd with. Both ISO800. Have to caveat that I used 5min exposures with UHC & 3min without as the histogram was well over at only 3m. Also, there's only 72min total exposure without & 110m with (running the mount & ASIair pro drains the battery rather quickly! Lynx astro power supply is in the post!). Minimal post processing, stacked in Siril, Photometric Colour Calibration, Green Noise removal, auto stretch & then just auto black point set (Pyastro) in GIMP, crop & export as jpg. Lot of background noise. I usually remove in Siril, but hard with nebulae as it's hard to avoid the 'emission' regions! So for sure the UHC is highlighting the Hydrogen alpha, but it does also distort the star colour. I guess maybe the answer is to have the camera modified (IR cut removed), so as to capture the emission but keep a more natural overall colour! Cheers, Rob

Hi HTH, I didn't pick up on this specific comment at the time, but can you explain more about losing the dark frames? Thanks, Rob

Well, the forecast high cloud hasn't materialised yet, it"s a beautiful clear night. Running at 800 without the UHC, so will let you know how it turns out!

Hi HTH, Thanks for your response. Understood in terms of "light capture". Will have another try at ISO 800 to start. But not sure how removing the UHC filter helps? Surely that's improving the level of 'emission" compared with the stars, with an unmodified camera? Cheers

Hi All, Interested to get your thoughts on this. I'm using an un-modified Canon EOS800D (with Skywatcher 200PDS), which from my understanding / interpretation of the online data has very good low ISO performance. My feeling (and experience to a limited extent) is that for Nebula imaging, going as low as possible in ISO gives a better 'dynamic range' (not that I'm even sure what that means!), i.e. allows more enhancement of the fainter areas without blowing out the brighter ones...? Note, I'm using an Explore Scientific UHC filter with this set-up. I've been trying to work at ISO 200, but obviously there's quite a trade off in terms of light gathering capability at such low ISO. Even at my current 5min exposures, the histogram is barely off the left. What are your opinions on this? Is there really a benefit to going as low as this or better to get more light & work at 400 or even 800? To date, I've kind of settled on 200 for Nabulae, 400 for Galaxies & 800 for star clusters etc... Although, being a nebie & currently struggling to get much imaging time what with learning how to use autoguiding, crap weather (until now, just as the moon is coming back in play) & the short summer nights, I'm looking for some advice as I'd really like to try & capture M16 before it's out of range for the year... Many thanks, Rob

Thanks for the additional comments 🙂 I've established the initial set up, app, connections etc... Just waiting on the weather now! 🙄

Thanks Stu & Dave. The mirror lock-up feature is just something I've always used, so I guess I've no evidence to 'compare' it's important! It's certainly a topic of much debate on various forums. The 200PDS (I think you have similar Stu) is rather unweildy on an HEQ5 mount, so I try to minimise any 'wobble'! But let's see... To be honest, guiding without having to use a laptop is my main aim with the ASIair pro. I was pretty happy with the camera triggering using my intervalometer. But the dither features using the app are appealing... Cheers, Rob

Ha, I'm going to ignore all the nagative or PI fan comments 🙉 now as I've already ordered the ASIair pro, hopefully arriving tomorrow! I do have a quick question regarding DSLR camera connection though if anyone can help please as it's not clear to me from the manual... I'm planning to use my Canon 800D as the 'main camera'. Looks like I need to connect from the camera data cable connection (looks like USB type 2 mini?) to the USB3.0 port. Do I also need to use the shutter release cable (2.5mm jack) or this is handled through the data connection? When taking images, are these then stored on the ASIair pro memory card, rather than the Camera's memory card? or both? I also note there's a comment in the ASIair pro manual saying to turn off the shutter lock up function? Does this mean that shutter lock up is covered within the ASIair pro software, or that this (important) feature is lost? Many thanks, Rob

Thanks Stu. I think I'm pretty well convinced & ready to give it a go... Will report back how I get on! Cheers, Rob

Many thanks for the feedback. So generally positive, but mixed & some negatives, even from those who appear to like it!!! 🤔 Am I correct in thinking that as long as your home WIFI is strong enough for the ASIair pro to connect to it, you can just connect the tablet to that home WIFI too and work like that? There's no to use the ASI's WIFI transmitter? Also, it's possible to use either the Synscan handset + ASIair pro, or bypass the handset & control everything from the ASIair pro. In the latter case, can you make minor ALT / DEC adjustments to frame the image? Don't understand why you would need to use EQMOD/safari in this case? Cheers, Rob

Hi all, I posted a while back asking thoughts on replacing my broken 'outdoor' laptop with a 'remote' setup and as seems to be the norm in this 'business', received many different opinions / options / preferences! I don't feel my IT skills are up to the Raspberry PI approach, so I'm down to deciding between a budget laptop or the ZWO ASIair pro. Wondering if there's anyone here using the ASIair pro with a similar set up to mine (Skywatcher HEQ5 pro mount (with a good helping of periodic error!), 200PDS, ASI120 / mini finder, Canon 800D) that can share experience / recommendation. I had only just embarked on using guiding, started with the PHD-2 software & was still using the Synscan handset for alignment / targeting etc & manual polar alignment. So my point here is that I'm not 'attached' to any existing guide / control set-up & happy to embark on something new, but I had seen some complaints that with the ASIair you're specifically limited to that 'ecosystem', so mainly just wondering if it's up to the job compared with a laptop set-up and all the possible software options that allows! ASIair certainly looks appealing from the perspecive of minimising equipment / hassle! But only if it gives good results! Many thanks, Rob

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Thanks, will have a play with the 2 layer approach :-). Being that I haven't properly learnt how to use Siril yet, I can't try the tacking of different exposures, as I assume you need to stack them separately & then stack them together?!

Here's my M5 attempt from early April. This was 180s, ISO400, but only about 15 frames.