ONIKKINEN

For a tripod, everything and anything on it consumes the supported weight. For just the mount head counterweights are excluded from the payload. But you should ignore whatever the manufacturer claims about the load. The claimed payload limits are not very helpful. For astrophotography you can typically cut in half the claimed number and youre pretty close.

I echo the advice regarding the tripod, if it is the aluminium one that is. Something must be done to stabilize that, or even replace with a steel tripod. Other than that, your best bet with imaging using this scope/mount combo is to go for northern targets at high declinations. The higher the better, because closer to the celestial poles the sky will move slower, and so be easier on a weak mount. It will not solve any issues with the mount, but will hide some of the symptoms in your images and you will have an easier time getting pleasing results.

Thank you Peter! New OSC cameras are pretty good, but i do wonder how different the image would be with mono. Surprising amount of Ha here even with just 1/4th of the pixels active for that. Thank you! 2-panel mosaicing is fairly straight forward with for example AstroPixelProcessor as long as there was enough overlap in the panels. You stack the images to their own panels and then let the mosaicing software figure out how to stitch them. Like you suspected the panels will look out of place if conditions changed significantly between them though, which is why i used the at the moment probably best tool - photometric mosaic script in PixInsight because there were changing sky brightness conditions for this night. There is a bit of user input required with the PI method (and you have to read the instructions to make sense of it all), but its not too difficult for a 2 panel image where you only have to make sure the one overlap area is sound.

Thank you Neil, i take it that my efforts to hide some issues with the stars were effective then because the data was far from ideal. The panels dont quite flow into each other in one area and some stars are cut off half way/maybe even missing, but im not sure it was noticeable unless you know exactly where the joint is.

Thank you! Preserving star colour is a strong point of the filter, it passes Ha-SII in red, O3 in green and an extra pass in blue centered around nothing specific in terms of nebulae. That extra blue makes working with stars easy since its not a pure bi-colour image.

Restart of the imaging season after the summer break in astro darkness. Still no astro darkness, but close enough it seems with around 3 hours of pretty good darkness to the south. 20x240s per panel for a total of 2h40min with the Antlia Triband RGB Ultra semi-narrowband filter: Stacked and prepared for mosaicing in Siril and mosaiced with the Photometric mosaic script in PixInsight. SPCC and BlurXT applied in PI, stretched in Siril with Asinh and histogram transformation and finalized in Photoshop with StarXterminator amongst other tools. Feedback is very welcome, not a proficient nebula imager myself with only a handful of targets from that category so far so likely could be improved in some area. -Oskari

Never ceases to amaze me just how much accidental nebula the RASA seems to scoop up everywhere one is pointed. Nice one!

On a decently calibrated computer monitor it looks a bit green but does have a lot more life in it. Might not be noticeable on every display though but it is on both of mine. Try "green noise removal" after the first Asinh stretch? You can also try before, or at any other point after colour calibration.

Actually i might take a page out of your book tonight. Still 2 weeks from astro darkness here but it looks like a clear night. Might be able to squeeze 2 or 3 hours while the sun is at a (hopefully) tolerable -12 to -14 degrees below the horizon. Probably still better than bortle 8 from which some people happily image anyway so might as well try. Now that i wrote this comment i am sure the clouds will appear in the next 3 hours 😬.

Its a very nice M31, would comment on the Siril colour thing further. That cloudy nights thread is frankly full of people who comment on the "issue" without understanding what it is that Siril does when stacking. Personally would not recommend reading through that thread without a few pints, and even then would not take any advice from it. Or more importantly, what it does not do. Siril does not apply any type of pre-stretch to any of the channels when calibrating which is something that some other software do. This is typically useful for daylight photography but for astrophotography it should not be applied because you want to have the data as linear as it could possibly be after stacking. So you can extract anything you want from the fully linear Siril stack, but you cant "unbake the cake" if the daylight colour transformation gamma nonsense is applied. This kind of colour transformation makes the data non-linear and certain processes like a photometric colour calibration will fail because fully linear data is expected. Now a helpful tip: Start processing with a crop, a background extraction, colour calibration and a stretch (in that order). To stretch the colours, or maybe better to say stretch the image while also better preserving colour you can start stretching with the Asinh transformation tool. I typically apply it at the full 1000 power, but sometimes that could be too much and you could go for something like 300. If the colours look deepfried at 1000, dial it back to maybe 300 and see what you get. Its also possible that the 1000 power stretch is still a bit dull, for which you could apply Asinh again at a small value like 20-50 (experiment on this) After this you can stretch with the simple histogram transformation tool to finish the stretch. You will see that the colours start to appear and they were not lost in the process somewhere. Below some examples from one of my own M31 images. First, only an autostretch in which the colours appear "muted": Then an Asinh stretch at 1000, followed by 25 and finally a closer dial in with the histogram transformation tool (manually, autostretch is way too much): For the second one i paid very little attention to colour calibration so it looks a bit off but i think you'll agree the colours are there to see and further adjust however you like. No extra saturation applied. This is also a mosaic image where the panels dont quite blend in properly so there are extra complications. For a simple one panel image it is much more straight forward. There is also another thing, M31 doesn't actually have a lot of the vibrant blues and purples you sometimes see in processed M31 images, so what you see in the simple stretch version (and your versions) is closer to "reality" than those blue/purple ones. Wouldn't claim that one is objectively better than another of course, i think the subject of colours is highly subjective anyway.

Great image, even in just mono! Will make an epic bicolour shot one day for sure.

The EQ6-r pro still shares the same flawed design of the altitude bolt, so no luck im afraid. However the AZ-EQ6 has a much better altitude adjustment system which i believe is similar to the modded rail kit. No issues using this at 60N for me.

Could be tilt/collimation related as the backfocus looks pretty good. If i were you i would leave it as it is and not introduce any other aberrations by trying to fix something that is really not a big deal. In a stacked image these small corner issues will be very difficult to notice, if not impossible. If you have BlurXterminator then this gets completely fixed for sure.

For the 2022-2023 season i had the pleasure of using my kit for deep sky on 28 nights (most on weekdays), and i think that's a great number. Would be content with half of that, or even less maybe. The last session was on the 23rd of april, and the next one will be no sooner than 2-3 weeks.. For northern humid climate dwellers this is the worst hobby imaginable, but since we (astrophotographers) are a little bit deranged it is no big problem. I actually think that in some twisted way the rarity of clear skies adds to the hobby because every time that happens its a long awaited gift from the heavens. Doesn't get old really and so far never had to think twice about going out if the clouds part.

Both look very good to me, but more importantly you should probably not focus on how the flats look when it comes to collimation, at least not make any hasty conclusions from them. The real issues make themselves known when you take actual images (and measure star sizes and so on). You could be in perfect collimation but still have an off-center fully illuminated circle because of tiny issues somewhere along the way (such as secondary not perfectly under the focuser, the mirror not exactly at the center of the tube, the focuser being slightly skewed and so on, list is endless and not very helpful). So my mantra is to not worry about funny looking flats if the images themselves are all ok, Having said that, you have a relatively small sensor camera so slight collimation issues will be more difficult to notice and if you're lucky you cant notice them at all. With larger sensors even very small adjustments can completely ruin one of the image corners but i think you will have a relatively easy time here.

This version seems to have done the trick with more familiar numbers for e-/adu and full well. Not seen a full well test go over 16.7k on mine yet, and usually gain 100 reports closer to 0.25 but this is pretty close to what i assumed to see. Ran it cooler this time, but i dont think this would affect the measurements greatly when dark current is still fractions of an electron per minute. Just because i was curious, i ran the test with my 678MC too and it worked well without anything special to note. As general feedback i do like how you have allowed testing only specific gain values, like what i did here to get a more accurate readout around the point where the camera goes into HCG mode (i believe 182). Interesting to see that the random telegraph noise is almost absent with this one.

My secondary is undersized so vignettes maybe 20% at 1x, but actually the paracorr makes this much better with its 1.15x barlow so there is less vignetting than native (reducers vignette more, extenders less). Just some food for thought. The paracorr is more expensive though so always a compromise around the corner.

The DEC drift here is due to just that. But its not a real issue as it seems very slow here. Realistically even with a 1 arcsecond polar alignment you will still have that drift because there is probably some cone error in the setup. Long story short a polar alignment of a few arc minutes is as good as it needs to be when guiding. No harm in going for more accurate one but also likely no gain either.

This video shows your RA periodic error in left-right movement and slight DEC drift in vertical movement. This is definitely not fixable without guiding, balanced or not. I would try to seek an answer as to why guiding had not solved the issue. So are the basics in check with guiding? Focal length and pixel size correct, calibration at the right place in the sky and so on? Also is backlash adjusted to be tolerable and the mount in good shape otherwise? Simple RA guiding should not be too difficult if the gear is set up properly so there might be something you have overlooked.

This is a decent way to treat slower newtonians too. Mine is f/4.4 natively and a bit over f/5 with a paracorr and its not easy to get good stars corner to corner. However if i crop to a micro 4/3 sensor size (294,1600MM) then in 95% of the cases images are great corner to corner. Newtonian + APS-C is quite demanding i would say. That is if one is a pixel peeper, if not then its workable for sure.

Flat panel is a plastic toy 25€ drawing tracing panel lit by LED strips behind a dew diffusion layers. Far from ideal but all channels calibrate well despite the dodgy levels so have not thought about that further. I will run another test later today, or tomorrow if i dont have the time. Got an idea, will run the test with another OSC camera (ASI 678MC) to see if there are similar issues and we can rule out some funny business with drivers as an issue.

Regarding those flats, something came to my mind just now. I have had doubts whether the old version of NINA and the Touptek driver in it engages the low noise mode since there is no toggle for it. So if there is something odd about those flats, that would probably be it. So might not be the most useful test subject.

Word of warning for the painted mirrors: The coatings in my secondary mirror (OOUK hilux coatings, so not the exact same as yours but anyway) have started to come off around the edges after i blackened them much like you did here. I cant be sure that the paint was the thing that did it, or the frequent dewing, freezing and thawing that the mirror undergoes around the edges. But anyway i only noticed this after having painted the mirror.

Here are 2 flats from my most recent session: Dark current at +5 shouldn't cause a jump so high in noise levels with the camera since it is so low to begin with but maybe since that is different between our runs. I will run it at a cooler temperature next to make sure this is not causing issues. For the rest of the issues it would be enough for the gain to be calculated incorrectly to also get the wrong read noise and full well values since those are derivative values. I already knew that the camera has little bit less than 1e read noise and around 16.5k full well capacity at gain 100 with HCG and low noise mode on so very similar to your mono measurements.

Well, this is the part that leaves me stumped because in what way is this implied? How is it that a light moving in a way you cannot explain must mean it is being controlled? There is some bias here in that i think you want to believe it is being controlled, when in reality there is not an atom of evidence to support this.