Yep nothing beats a dark sky site 🙂 I tried 3 times to capture the C/2022 E3 (ZTF) from where I live near Chicago but I could not get the faint tail and other details. But I went to a dark sky site 1.5 hours away from where I live and I was finally able to capture the full comet! I put a timelapse in my YT channel. Thanks for this video, just proves the SNR is so much better when you don't have all the LP shot noise!
Interesting video & weirdly we're on vacation in the UK but sadly never had a chance to image anything, pretty much everything we own astro wise is all second hand I've no issues with anyone having the same as usually any bugs have been sorted along the way. Very interesting about how much more data is required from 2 different Bortle zones as my other half always struggles in a Bortle 7 where I'm in a Bortle 4 & can get some pretty decent results. Great content as usual & your camping location looks stunning to, clear skies!!
Great video! Loved the pace, tone and feel. Very informative and easy to understand. Not sure how I missed your channel before (algorithm - aaarggh). Subscribed. Greetings from the cloudy UK 👍
Im glad i live under bortle 2 skies. The results under bortle 7-8 skies is far worse than i first thought, thinking maybe 4x the data needed on dim stuff..👍🏻
Interesting analysis. From my Bortle 7/8 sky I mostly use Narrowband filters, shorter exposures (3 to 4 minutes per exposure) with longer integration times and I get results I’m happy with. I’m sure they don’t match up with those pics taken at dark sites, but over here in Germany dark sites a few and far between 😊. Nonetheless, remember that the moon cycle also has a direct influence, even in dark sites. Thanks for the video, enjoyed watching it and will try out the app.
Thank you! Yep, narrowband filters are a lifesaver. It'd be interesting to do an analysis of narrowband filters in dark skies vs. light polluted ones. I'd suspect the results wouldn't be quite as dramatic as in the video, but it's worth a shot!
The late, great Samir Kharusi did a fine exposition on this many years ago and the difference between a dark location and a light polluted site can be x20-x40. Potentially disheartening for those of us in highly light polluted skies. Narrowband filters and fast optics will help but nothing beats a truly dark location.
Yep. M3 is such a bright target that even the x12 result I got is still a lot better than the faint nebulosity in a lot of targets. It's so difficult if not impossible to image dark nebulae and a lot of reflection nebulae in light pollution.
Do you have any way to contextualize “desired SNR” for images, such as in your SNR calculator app? For example, say I want to find out how much time I will need to get a “decent image”. I haven’t used it before, so I have no context for SNR measurements, and don’t know if, say, SNR 50 would like like a single sub, or a good finished image. Do you have any examples, say, of images with different SNRs? Great video, I love your storytelling style!
That's a good question! I think a good rule of thumb is that 30 is OK, 60 is pretty good, and anything over 100 is really good. In this video, ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-CNQ0DU5GbIQ.html I calculate the SNR of M101 from my Bortle 7 zone. The core of the galaxy probably has an SNR of 120 or so. The closer spiral arms are probably around 60, and the very outer spiral arms around 20.
Yep, its like shooting fish in a barrel when you go to a dark site. The difference is huge and not to be under estimated. I'd say at least 20x greater... Making your measurements on Ha nebulousity might even prove me wrong... It might be even worse?
Much to learn, good job , lots of patience. Q?, what does the stars look like in PHD2 with your OAG? i m trying to get mine to work with the right spacing...
@@deepskydetail i followed ZWO OAG recommended spacers but my stars are bananas or seagulls, so PHD cant lock on a star. i gave up and put it all back in the box this spring, but i really want to get rid of the top guider. my Telescope is a SF 90mm F5.5 /500mm FL. Any hints would be welcomed or even a picture of your image train from the Camera to the focuser tube would help. i can give you my Email.
You can email me at deepskydetail at gmail. It could be that the prism is too far on the edge of the imaging circle. The OAG should allow you to adjust how far the prism goes into the tube. I would try putting the prism closer to the center of the tube and seeing how that goes. Also, changing the PHD2 star settings might help too (the minimum FHWM and HFD values). They may be too large. A guide scope's stars are usually bigger than in an OAG. It won't lock on because it wants a bigger star and is afraid it's locking onto a hot pixel.
interesting video , but remember the map pollution data is (2015) too old , in my case ,following the map (2015) my SQM 17.55 however my reading real time with SKY QUALITY METER is SQM 16.84. there is a different ,thanks you
a more brought description for the bortle scale Would be Better for this comparason , here's mine: bortle 9 to 5 is the sky in any large settelement , . 5 to 3 is the countryside sky , . 2 is completely dark sky , . and finaly 1 is exceptionarily dark sky but still a very informative video , I like it :D
Hi, in Siril what do you think about PSF tool for sequence? You can pick after registration (aligning images) stars and choose SNR on the plot. Now you can pick same star on all of the images in the sequence.
That's a great idea. The samples from both sites are from the same exact areas of M3, but doing it your way would have made things a whole lot easier :)
