CloudMagnet

Good thing about this hobby is you never stop learning -there is always more you can do

Might just be down to the Bortle 8 skies. You are just reaching the maximum limit of what that setup in that location is capable of. Someone in Bortle 2/3 would likely hit that signal to noise ratio in a fraction of the time. I'm sure someone with more knowledge can work out mathematically, but that would be my assumption. I have deliberately avoided the Iris nebula from my Bortle 6/7 skies as I’m sure I read that somewhere that it would take me around 40 hours to reach the same SNR as someone taking 4 hours in a proper dark sky zone. You must just be tending towards the natural minimum noise possible and no more dithering can remove noise beyond that limit. Only easy option to improve further would be to run the camera at a cooler temperature. Anything beyond that is tweaking at the edges. Such as using more dark frames or using dark flats (if not already), looking at gain settings and exposure to minimise read noise.

Very interesting! Huge difference from 2-4-6 hours then a steady drop in difference as we would expect. Think that the practical limit is still around that 10hr mark as before. Main difference I can see from 10 hours onward is just around the very faint outer arms near the top left. Some aren't even visible in the early pictures but do show up later on. Might be helped by the steady darkening of the background-I assume this is the noise cancelling out with longer integration. Well done putting that together, exactly what I meant by keeping the brightness of the galaxy the same for a better comparision

Were the images dithered? I would expect that would even out any noise with higher integration time (fewer frames occupying the same exact space). In terms of making the images the same brightness, either by eye would be ok or using the eyedropper tool in Photoshop that will give you a brightness reading of a pixel sample- just put this in the same place on every image.

Hmmm, my observation would be that there doesnt seem to be much change in background noise from 4-6 hours onwards. I thought that this would slowly improve but hits a limit much earlier than I would expect. Thank you for putting this together. Would it be possible to have the galaxy the same brightness in each picture as well? Makes for a nice comparison for the finer detail in the core/dust lanes

It also depends what galaxies you are looking for as well, try for some of the bigger and brighter ones first so you get a feel for what you will see. Its nothing like the pictures you will see on the internet, mostly just grey smudges for the most part. Also make sure that your vision is fully dark adapted as much as possible try to avoid any bright light shining on where you have set up the scope. I also find that using "averted vision" -where you look slightly away from your target and see it out of the corner of your eye really helps pick out details as well.

Sounds like a plan, its worth doing to find what the practical limit is. With limited clear nights spending 20+ hours as a big commitment if its not really giving much benefit.

Thanks for putting this together, as you said looks like 10 hours onwards is the start of diminishing return. Definitely useful to see it in practice. Have you done anything similar for other types of targets like galaxies or emission nebula to see if the same integration time holds true? Would be interesting to look at how different surface brightness could affect the "best" integration time as well.

Fantastic, I always think this is an easy target until I look at my results the morning afterward. I would honestly be interested if you could put together a decent image just from the 13 hours thrown away!

Yep, exactly Although where I live, the chances for this hobby are rare (see username for explanation) in some ways that what makes it more special. I still get nervous in a good way when a clear night is planned because I know how rewarding this can be when everything works. Then spending an entire night outside from dusk to seeing dawn knowing that I've captured an image from thousands/millions of light years away or seen detail on other planets cant be beaten. No other hobby can give the same.

Yep, astrophotography started for me by holding a phone camera up to my scope lens. Never really looked back since. But I recently spent a night just looking at the moon, no stressing over a fancy camera, panicing about alignments, software or triping over wires and just enjoyed the night sky. You are right by saying that no one can take that away and for once it was a case of just relaxing and taking in every little detail. The good thing about this hobby is you can make it as easy or as complex as you want, your choice!

It is a point that you can just look online at any number of pictures, but for me most of the fun is seeing it with your own eyes, or for astrophotography, taking a picture in your garden with your own equipment and hard work. I personally get more excited with seeing the GRS on Jupiter, Saturn's rings or craters on the moon in my own garden than looking at anything done with a multi billion pound space telescope run by hundreds of people. I suppose I think of it as "good honest work" by learning how telescopes work, setting everything up correctly and the endless pit of complexity that is astrophotography to produce something over time myself than an quick evening on google images.

Yep, basically! I would look for one with a zip up front so that you can keep the warmer air trapped in with the laptop but thats the idea

I bought a "tent" covering for mine that has really saved me a few times. It has a zip up front so when im not looking at the screen, the laptop is completly covered. Never had any problem with dew even when the whole scope was covered in frost. Just also cut a couple of small holes on it to allow wires through for USB's and also leave a cloth ontop of the keyboard as well to help hold its temperature.

That must be quite a small FOV to be imaging at, so nicely done. I would recommend Gradient Exterminator to help get rid of colour/moon gradients. Always does a nice job to even everything up.

Its the same for weather. What used to be called "winter" is now a weather bomb or polar vortex of doom, dont know where it will end really. Cant wait for the next one that DOESNT have a name attached to it- might be more unique than all the others!

The Celestron 130EQ was my first scope, and i never imagined you would ever be able to capture any decent image with it at all, so well done in getting this far! Probably just some extra calibration images needed, definetly flats/darks will be the biggest help. Adding more imaging time as well will help with noise reduction as well.

Nicely done! I think getting the first "proper" picture is almost a bit of a relief as you can put pressure on yourself to get a result of all the time, effort and money invested. I think you have done well not to fall into the trap of over processing the images as well, can be easy to do sometimes. As you learn the equipment and the best settings to use, this will just improve with experience and you will likely get more quaility data to work with

hmm, might have a try at that and see if it makes a difference with the tube rotated. I always set it up at the exact same angle just for keeping the center of mass in balance, so the only variable is the rotation of the camera itself. OP might just need to experiment to find how the camera needs to be rotated to produce a matching view with Stellerium. First deciding on the angle the OTA should be rotated (keeping balance in mind) and then sticking with it. Only afterwards then finding the angle of the camera required to keep consistancy between different nights.

No tube position doesnt matter (i think), as long as the camera is attached with the text the right way up and parallel to the focuser knobs as in the picture below, then it is always lined up to match stellerium. I rotate the tube itself so that the camera forms a near straight line through to the counterweight shaft. That means that I can balance the scope in declination as otherwise the camera weight pulls the scope down on one side.

With my camera, the image sensor matches the Stellerium view when the text on the back of the camera is upright and this text also lines up parallel to the focuser knobs (if that makes sense). So the camera in this position is what I count as "0" degrees. Rotating the camera 90 degrees clockwise also matches with adding 90 degrees to the camera angle on Stellerium as well. Make sure you use the equatorial mount otherwise the image angle will be all wrong. Handy tip to remember if you ever use APT to control your camera is to invert the image preview horizontal and vertical when you image in the western hemisphere as it will be back to front otherwise.

This is the main one i use for realtime pictures: https://meteoradar.co.uk/clouds-sun-UK-Ireland#

Yep definetly seems sound. On point 3 I would also consider at least a modified DSLR or even a dedicated astronomy camera. If you are really going to be chasing nebulas then you need a camera that will be sensitive to Hydrogen alpha to get the best results. Unmodified DSLR cameras tend to be lacking for this but your current camera will do for a start while you build up other equipment. Longer term, a cooled astronomy camera will give the best results so its good to plan for that early on as the cost can get high quickly.

If you have an accessable mains supply, you can use the ZWO branded power supply: https://www.firstlightoptics.com/power-accessories/zwo-12v-5a-ac-to-dc-power-supply-adapter-for-cooled-cameras.html Might take a bit of time to deliver but at least you dont need to worry about connecting the wrong thing. This is what I have used for my camera and no issues at all. Would advise to keep a cover over the power box to stop any dew getting to it.

It really does depend on the object I think. You dont want it to cross the meridian unless you want to do a merdian flip. A way I do Orion is to image M42 for the first half of the night, then when it crosses the merdian, flip the scope and do the Flame nebula- you get both in the same night Otherwise, I plan my targets by normally looking at when they will rise above any obstructions (houses, trees) and then start imaging from there. If you are doing a full night, then the seeing will averge out over the time anyway. If you pick a target starting at maxium height, then the seeing will just get worse as the night goes on for a lot of targets so it makes little difference I think.