BrendanC

Interesting idea! But I wonder how undoable that is?

Here's another example, using a slightly better image of mine. Colour: Mono (from here: https://stargazerslounge.com/topic/326197-ngc-7000-hyperstar-c925/) Combined: It works better when I blur the colour image behind, and overlay the mono image. Now I look at this, I'm not sure it'll work. But I'd still be interested if anyone else has taken this route, and with what level of success. It would just be good to keep using existing equipment and upgrade one step at a time rather than wholesale change. I've come across some threads on Cloudy Nights where people say this works, but nothing here. Thanks, Brendan

Hi all, I've been imaging with an EOS1000D with IR filter removed for the past couple of years. Had a whale of a time with it, and it works very nicely in my Bortle 4 skies. However, I may be moving to London soon, and I'd very much like to continue this hobby, even though it's probably the worst place in the world to do it! So, I've been considering narrow band imaging, cooled mono cameras, filters, filter wheels, all that gubbins. But I recently had a thought: instead of going straight from DSLR to mono with filters etc, and all the steep learning curve and cost that entails, could an intermediate step be to just get a cooled mono camera for the luminance, and combine that with shots from the DSLR for colour? I just tested this by combining my shot of the Horsehead - one of my first ever DSOs and I know there's a ton wrong with it, but it's just for the colour - and combined it with a shot taken from https://www.astrobin.com/full/397555/B/ for the luminance, using the Luminance layer blending mode in Photoshop. My colour version (over exposed, too much stretch, noisy, etc etc): Rick Wayne's mono version, which I've linked to above: Combined - just very roughly, just as very quick test: So in theory this is possible, even if the test image above is a little rough and ready. For example I can see that it's a bit noisier than I would like, but I don't know whether that's just me being a bit fast and loose with the overlaying etc. Is this a 'thing'? Do other people do this? Is it a valid intermediate step between OSC with a DSLR, and mono? Or should I just take the full step and go for filters too? I tend to shoot nebulae and galaxies, although I'm prepared to believe that one or the other (or maybe both) won't be possible from The Big Smoke. Thanks, Brendan

Thanks! It depends. For clusters I can generally get away with a couple of hours. Galaxies about five. Nebulae about seven. More integration means less noise but also, oddly, I've noticed that the colours also definitely improve a lot with integration time too. I also use calibration frames - darks, dark flats, and flats, no bias. I take 25 flats on the night, have a 25-frame-based master dark flat that I re-use, and then a darks library for different temperatures. I know you're not supposed to use dark libraries with DSLRs, but what I've found through extensive testing is that they really do work, for me at any rate.

Thanks! Yes it's a fabulous little performer.

As we come to the end of another astro season, and the light nights mean no astro darkness from end of May until end of July (in the UK at least), I thought I'd post some of my shots taken over the past year since I got a second-hand NEQ6 and sold my 130P AZ. It was a huge step-up and I had to improve my technique because the improved accuracy of the mount really showed up all the things I was doing wrong. Anyway, now I've learned about guiding, calibrating, dithering, polar alignment and whatever else, I love my little 130PDS. The only thing I wish I could change is those iddy-biddy little bitemarks the focuser tube takes out of stars. All photos taken with an EOS1000D with IR filter removed, some are guided, others not, captured with APT, stacked in DSS, post-processed in Affinity and Topaz AI Denoise. They're all pretty much 'the usual suspects', they won't win awards, but I've really enjoyed taking them (as well as being very, very frustrated a lot of the time!). I hope it's OK to share so many in one post...

There is such a thing as a dumb question btw. I was once asked by someone at work whether the Moon was bigger than the Earth.

For some bizarre reason my mount refuses to slew to NGC 7822. No idea why.

Would anyone like to try and get something out of an image taken under possibly the worst conditions? So last night it was a virtually full moon, very high and bright, throughout the entire night. Somewhat foolishly I thought I stood a chance of capturing the Bubble Nebula, because it was on the other side of the sky, and because, well, I don't find clusters very interesting. In the end I had to take 60s subs because anything longer pushed the histogram too far to the right. Oh, and when I examined the subs, it was clear that most of the shots had been taken through the branches of trees, which I thought would be just out of the FOV. I was wrong! Anyway, this is the best I can get out of it. Pretty bad, and I was going to dump the lot, but then I thought maybe some of the good people in this forum might fancy having a go. So, if you want a bit (ok, a lot) of a challenge, here's the stacked FTS file. Good luck! https://1drv.ms/u/s!AqovBuVZMwj3jbgpHZ_1SHVkyWaCIg?e=s864Wi (119MB) If it helps, details of this shot are: • 4:52 hours of integration at ISO800 from 292x60s subs • Bortle 4 sky, 4:52 hours of moon at 93% phase, 40° height • Calibration: 25 flats, 25 dark flats, 50 darks • Hardware: Sky-Watcher 130PDS scope (F5), Sky-Watcher NEQ6 mount, Canon EOS1000D DSLR camera with IR filter removed, Sky-Watcher 0.9x coma corrector, Datyson T7C guide camera (ASI120MC clone), Angel Eyes 50mm guide scope • Software: polar alignment with SharpCap Pro, guiding with PHD2, capture with Astrophotography Tool (APT), stacking with Deep Sky Stacker (DSS), post-processing with StarTools, Photoshop CS2, Affinity Photo and Topaz Denoise AI Cheers, Brendan

I used the Synscan Pro app and really liked it. I connected to my old Sky-Watcher AZ mount via the handset and it worked well. Then I got a second-hand NEQ6 and it just would not play ball. The only way to get it to work was using EQMOD with a direct connection. EQMOD has mount limit control, which is very handy for preventing your OTA from grinding into your tripod's legs if it overshoots. I think it comes with other features that I haven't explored. But, for just controlling the mount, it may as well not be there - in exactly the same way as the Sky-Watcher drivers just get on with the job in the background. So I'd say, if your system's working for you now, carry on as you are. I was very reluctant to have to go the EQMOD route after getting my workflow all sorted. It wasn't that hard in the end, and it did succeed in connecting to the mount where Sky-Watcher's own software failed, but I don't really know that I gained any more functionality. And if there's one thing I've learned so far, it's not to mess around with a system that works, even if it has little annoyances or glitches that you have to work around occasionally! I'm sure others will know more about special stuff EQMOD does, but that's my take on it having used both connection methods.

Hi all, When I'm stacking in DSS, I put my lights into separate groups according to temperature, and then add the matching darks for each temperature from my library. All good so far. It just occurred to me however: when I'm adding the darks, I generally just highlight them all for that temperature, and add them all - which means that I add all the individual darks AND the master dark. I do this because I'm lazy, but also because I like to hold onto the individual files come the day I decide to use a package other than DSS, for example APP or, heaven forfend, Pixinsight. So, my question is: does it matter? If I add individual darks, and the master dark, will I end up with some sort of horrifically overblown master dark? Will it get more pronounced every time I do this? Should I be more sensible and just use either the individual darks, or the master dark? Or, does it not matter? Thanks, Brendan

Thank you! I think you're right about the elongation of the stars. I was forced to use 120s subs because guiding wasn't working at all (turned out I'd moved the guide camera and PHD2 didn't like it until I recalibrated the next day), and I thought I could push the mount to that time without guiding. Looks like I pushed it too far. It's an old(ish) NEQ6 but has the belt mod. Maybe I should get it serviced or something sometime. The star colours might be fixed from now on because I discovered how to use the Max RGB feature in StarTools (which I use for most of my post-processing, I generally just use Photoshop and Affinity for additional tweaks). I discovered that I had a lot of green in one image, which might mean I can go back and fix the others sometime. Interesting idea about processing RGB and Lum separately. I used to do that in Photoshop to stretch each channel but not since using StarTools. I don't even know how to do that in ST, or even whether it's possible from a DSLR image. But I'll have a look. For the noise, I use Topaz AI and it works well, but recently I've noticed more noise than I'd like. So, last night, I ran a test on M64, in which I did equal times of 120s, 180s and 240s exposures. I'm actually processing them all now, so let's see which one yields the best results. Really appreciate the feedback. Thanks again. Cheers, Brendan

Thanks. Although nobody seems to think there's a problem!

Hi all, I recently took this: Now, I quite like how the galaxy turned out, but the stars leave a lot to be desired. They seem a bit noisy, bloated and ill-defined. I'm not sure what's wrong. Am I overexposing? Is it noise? Have I overdone the processing? If so, which bit? Are my calibration files crap? Or is it just a basic limitation of my kit? Any/all comments/suggestions/recommendations/ideas/thoughts/opinions/insights/questions welcome. Here are the details: • 4:42 hours of integration at ISO 800 from 141x120s subs unguided (240s subs were planned but guiding wasn't working) • Bortle 4 sky, 45 mins of moon at 6% phase • Calibration: 25 flats, 25 dark flats, 50 darks • Hardware: Sky-Watcher 130PDS scope (F5), Sky-Watcher NEQ6 mount, Canon EOS1000D astro-modded DSLR camera with Sky-Watcher 0.9x coma corrector • Software: polar alignment with SharpCap Pro, capture with Astrophotography Tool (APT), stacking with Deep Sky Stacker (DSS), post-processing with StarTools, Affinity Photo and Topaz Denoise AI I didn't bin the image. I nornally 2xbin in StarTools to increase SNR, but sometimes, if I want the central object to be larger, I don't. So perhaps that has something to do with it too? If it helps, here's the larger, binned image, in which the stars are a bit better (I think): Or are they ok and should I stop worrying? Thanks, Brendan

Plus... Sky-Watcher's own Ascom drivers didn't work with my second-hand NEQ6 but EQMOD did..

If you're doing this with a laptop then I highly recommend Bahtinov Grabber. It basically tells you when you're in focus by analysing the Bahtinov mask image. The Bahtinov Tool in APT is based on it, but odddddddly, Bahtinov Grabber is better. I struggled with APT's implementation until I read about this, now I use it all the time: http://www.njnoordhoek.com/?p=660

Oops, sorry, should have included it before! Here you go: https://www.cloudynights.com/topic/657429-how-to-use-sharpcap-with-a-dslr/ As those instructions say, the camera will just keep taking shots once connected. I think that's how it's supposed to work. When I first tried it, I assumed it wasn't working and uninstalled it. Then I gave it another go and found it works wonderfully well with Sharpcap Pro's own Polar Alignment tool, which then immediately became a game-changer for me. It should be ok with Canons but it's a bit hit-and-miss. Fingers crossed it works for you. If it doesn't seem right at first give it another few goes. Good luck!

Yep, with open source Ascom drivers.

I knew it was a very, very, very long shot.

Thank you Vlaiv. Once again, you give the definitive answer!

Hi all, As a test, I just decided to try processing an image without darks. This was after processing one from quite some time ago before I started using them, in which I was surprised at how noise-free the image was. What I got was not what I was expecting - really severe vignetting right around the central object. I'm confused. I thought that's what flats were supposed to correct? Which I used. And dark flats. I didn't think darks had anything to do with this - just removing sensor and read noise. Or am I wrong? Again? Thanks, Brendan Post edit - I guess this should be in the image processing section, apologies, mods please feel free to move

Brilliant stuff, thanks all!

Hi all, I took this shot a while back and now I'd quite like to know which bit of the moon I got! I'm no lunar expert. I've tried matching it to moon maps without success, and using software called LVT which I can't get to work. The problem is that I also don't even know which way up it should go - in space, there is no 'up' or 'down'! So, I know this is a pretty lame question, but can anyone help identify it please? Thanks, Brendan

Hi all, I've tried to use the Sharpcap Sensor Analysis several times, but it always says the image is too bright or too dark about midway through and stops. I was wondering whether anyone else has got it to work with an astro-modded EOS1000D (IR filter removed) and if so, whether they could share the results? I know it's a very, very, very long shot but it's always worth asking! Thanks, Brendan

Forgot to mention, I also have a coma corrector in the optical train. I happen to know that it can cause internal reflections sometimes, so if I get the spikes again, I might try it without. I sort of don't mind if it's very unique to this object/area of sky, but if it can be fixed, I'd like to fix it.