ONIKKINEN

Siril is kind of the fastest one out there at the moment, and not by a small margin. At least on a windows machine when symbolic links can be used and so a lot of the file writing can be skipped, im guessing its not possible on a mac? (never had a mac, wouldn't know) DSS and in fact any other stacker out there will also write temporary files, but not to the extent that Siril does them since Siril keeps all of the intermediate files of all the calibration frames, light frames, registered frames etc. Best solution would be to free up some hard drive space. Surely you could move some files from your main HDD to the external one? Another option is to do the stacking in phases. First stack your darks into a dark master, delete the intermediate dark .fit files as you no longer need them. Then the same for bias, and flat. Then calibrate your lights, and afterwards you can delete the intermediate .fit files as you now have the preprocessed ones to use, then you can register the preprocessed lightframes and delete the unregistered ones. This leaves you with registered subs, the bare minimum storage space needed in any stacking software out there. If you dont have enough space to hold all the registered frames at once in your hard drive, well, best of luck because then the situation is really dire.

I oriented it this way because that's what it looked like when capturing the data, no clue which way it should be moving in reality!

Imaged from a bortle 4-5 area with an 8'' newtonian at 1020mm fl and a rising cam IMX571 so the image is a bit too zoomed in to appreciate the entire comet, i think the tail would continue for a lot further than shown here (and other images). 64x 60s stacked on the comet: And an animation of the frames that went into the image showing the movement: cometanimation.mp4 You can also see that my scope was still cooling when i started imaging, but it is what it is, not going to produce a pretty untrailed comet and stars image but the startrailed one wont care if the starshapes were bananas.

I very much like the image in the forum preview or scaled to monitor, but viewed at 100% it seems very soft and its hard to make out detail because of it. Looks like you drizzled the data as the image is so big? Nothing much wrong in the image otherwise, and if you look at the image scaled to the monitor then no big deal, but consider not drizzling (and maybe even binning x2?) to get a better sampling rate and ultimately a much better signal to noise ratio, allowing you to sharpen the image a lot more. Looks like the high SNR parts of the image in the flame and around the horse could be sharpened and improved quite a bit if you didn't drizzle or even binned x2 after that.

For the noise you need to expose longer, a lot longer. Your camera (from what i could find) has read noise in the range of 7e- to 12e- and your 300s subs are definitely not long enough to account for that. The exact length of exposure that is enough to cover that depends on your sky conditions, but i would guess you need to go at least 10 minutes to get significantly less noisy results. The same applies for your calibration frames, the more you stack them the less you add noise in from them. 25 is not that much, you would do well to at least double that number.

It looks more like atmospheric dispersion as you have separated red and blue at different sides of your stars. They are also separated vertically as blue in this case would be higher in the sky than red if you shot this while the horsehead was close-ish to the meridian. It happens because the target is too low in the sky (below 40 degrees is bad, above 60 is where it starts to not matter), which is not something you can do anything about but its fixable in post. You need to extract RGB from the stack and register the frames against each other and it may fix the issue by properly aligning the colour channels. You will still be left with the blue halo because of the chromatic aberration in the fast doublet lens, but it should be more symmetric at least. I will assume you used a colour camera here as that is the how you capture all the colours at once. You have another option which fixes this issue more robustly and from the source and leaves no artifacts behind, but its a lot more work to do. You first calibrate all the frames WITHOUT debayering them yet, then you can split your frames using the CFA_split or seqsplit_CFA commands in Siril (PixInsight can too if you have it). This splits each of your raw OSC subs into 4 mono ones : 1 red, 2 different green ones and 1 blue. Then you can choose one of these frames as a reference frame for registration and stack all the frames from the different channels to that. That obviously means all the RGB separation issues are removed as every frame is distorted and transformed to correctly fit the reference frame, leaving you with mono stacks that colour align perfectly!

HFD - Half flux diameter is a unit that measures the size of your stars in the image (in pixels in this case, to convert to arcseconds you need to know your pixel scale). Tilt measures the difference in star sizes between different areas of the image. Then the rather self explanatory number of stars detetcted, and used in the calculations and lastly off-axis aberration which i think means how much things like coma, field curvature, backspacing etc affect the typical star size. Your tilt is pretty bad at 32% difference between different sides of the image indicating some collimation issues in either your mirrors or in your focuser and imaging train, mechanical issues with the tube/tube rings/other mechanical parts flexing or what is common in newtonians = a mix of all of them. But another issue is that there are only 104 stars used for the calculation which seems really low. Its low enough that there is severe bias in the measurements, as you can see with most of the stars being on one side of the image and the other side is mostly dark. So is it that you really have issues in the imaging train or is it that the measurement is incomplete? Anyway, thats what all of that means. For CC to camera distance evaluation you need to have the scope fairly well collimated and most sources of tilt eliminated or you will have a tough time getting the correct distance. And for the actual evaluation itself you might find the aberration inspector tool more convenient.

Could not see it naked eye last night under Bortle 4-5 skies (transparency was bad). Very obvious in my 7x50 binoculars and a 90mm frac though, impossible not to find really. Not moving all that fast, certainly couldnt see it move in real time. In terms of visual oomph i would say it was third place in brightness and size, just after M31 and M42.

Isnt that just the difference between the PixInsight plugin and the Photoshop one? The PS plugin doesnt need the unscreen stars or generate star image option since those are easy to do with the layer blending modes whereas with Pixinsight its not so easy.

Green makes sense for broadband where most of the signal is roughly neutral white so brightest in green. Also for daylight photography where sensors are designed to work best. The AP market is probably pennies for Sony so doubt they want to design a bayer matrix with a different set of filters.

If you have light leaks or a different offset (or both) in your darks, that would also create a funny looking gradient that is difficult to remove. Might have been why gradients are worse with them? Darks should ideally be taken with the camera off the scope and completely plugged so that not a single photon gets to enter the camera. I take mine in the fridge now, helps with cooling too.

Light frame looks decent, tilt measurements show nothing really and the frame looks good so i think your primary to camera collimation is plenty good enough. The flat frame does look off-center as shown above in a previous comment, which would suggest your secondary mirror is not perfectly centered under your focuser, but this wont stop the subs from being calibrated as long as they match the lights. Tried a bit of pixel math by first subtracting the bias frame from the light frame and the flat frame, and then dividing the calibrated light with the calibrated flat and it works out just fine to my eyes and it looks like your lights and flats match well and correct the off-center illumination, result in ultra stretch mode below: There is a gradient but it looks quite linear to my eyes indicating a normal sky gradient from light pollution. Doubt this was the difficult gradient you mentioned? But since you mention using no darks, does this mean you do no dark calibration to your light frames at all? You need to remove offset somehow, and for this purpose a bias frame can be used as a dark frame. But calibration where you dont remove offset at all from your lights will always result in a completely failed flats calibration, like below where i subtracted the biasframe value from the flatframe, but not the light frame (like you would in stacking if you were to not designate the biasframes as darkframes): If your stacked result looks like this, then the solution is to start using dark frames, or just use your bias for both bias and dark frames (works fine with your camera). As for the secondary not centered issue, im not sure i would bother fixing that because i am lazy, but in case you want to, a concenter eyepiece makes the job as easy as it can be made in case you had not used one already.

Like the image, and also like the green in it rather than the typical hubble look. Maybe because its less common? Anyway, great image.

There is something special about doing it yourself, but not all agree to the extent that has to be done by themselves. (AP discussions are technical gibberish to most and i would argue most people are put off by it). People who like EAA but not "full" astrophotography are one group who fit into this analogy well, they are still producing an image in the end although with a great decree of automation. Surely they feel like it is their image and not the same as having a look on Astrobin? Even with smart scopes like the Stellina, EVscope, Dwarf2 and others i think the person orchestrating the image feels it is their own rather than entirely done by machine. Another analogy would be learning to compose music with a computer using synthetic instruments. You are still learning to create music, but can skip 5 years of guitar lessons. The meaning of DIY is vague and entirely subjective. I would like to say im in the "want to do it myself" category, but honestly there is no way to tell unless i get to try full automation one day, perhaps i do like it? Progress progresses and we are all left behind, that is for sure.

My mini-PC sits on a quick couple wallmount ziptied to the tripod spreader of my AZ-EQ6. Best image of it i could find: Its not too bad in terms of cable drag, but since i have no powerbox it means one DC cable for the camera goes all the way to the battery on the ground. One USB3 from the mini-PC to the camera, and one short cable from the camera to the guider sitting in am OAG. This is a very convenient and easy way to mount it, but maybe not the most elegant. Benefits of this method would be less strain on the mount as its not on the scope, and maybe less thermal effect since its far away from the scope. I want to keep scopeside waste heat to a minimum as with a newtonian there may be tube currents that ruin sharpness otherwise. And its easy to do, so if youre lazy its a 1 minute job to ziptie a wall mount to the spreader.

I dont think its a thermal binding issue since the drop in temperature was only 4 degrees. 10-20 degrees, maybe, but definitely not 4 degrees unless you were a micron off the ideal bakclash setting. Something else is likely the culprit and what that is would be difficult to guess. Many reasons, too many to guess from. If you post a guide log here someone may be able to take a better guess as to why it got worse.

I would say its only a matter of time when we have a tool like an all encompassing AI where the user needs little to no input to turn a linear file into a processed, sharp, colour accurate and aberration free image (EffortXTerminator maybe?). Not saying its the next few years but 10-15 years? Maybe, the field of AI infused software moves so fast its really hard to tell where it goes next. Also not a fan of something like this, but there is a market for it i think so only a matter of time it happens.

Absolutely, another great option. Maybe even better since you dont have to deal with windows and you already know what youre doing. The main point is that Asiair is brand locked and all the other options like an RPI or mini-pc are not.

Youd be surprised how quickly you start to take images that resemble or greatly surpass the typical google image search or wikipedia image. From your list i would point out a few things. First, the Asiair. Great product BUT it locks you to ZWO products forever, so not the best choice in my opinion. I dont mean to start another mini-pc vs Asiair debate but you mention IT and so being tech savvy, i would recommend you replace the Asiair with a win10/11 pro mini-pc that you control with a tablet or phone via remote desktop. That way you have freedom of software and brand of camera, and ultimately a longer lasting product because of that. This was maybe not good advice for a total beginner to AP but you seem to be the type of person to figure out the tech side of things. Another point in the list, which couples with the mini-pc thing is a camera with a larger sensor, namely the IMX571 APS-C sized one. Sold under many names, like the ZWO 2600MC, QHY268, Altair 26C, Rising Cam ATR3CMOS26000KPA (great name). The ZWO one is not the cheapest choice and its not even close. This will be more expensive than the 533, but in my opinion well worth it. Rising cam from Aliexpress at 1260 USD (legit seller): https://m.aliexpress.us/item/2255801172998984.html?pdp_npi=2%40dis!USD!US %241%2C355.00!US %241%2C260.15!!!!!%402103309e16740606543726436e8c5d!12000027453462720!sh01&spm=a2g0n.store_m_home.productList_2222141.0&_fs_=true&gatewayAdapt=glo2usa4itemAdapt&_randl_shipto=US Altair astro 1165 GPB: https://www.altairastro.com/altair-hypercam-26c-aps-c-colour-tec-astronomy-camera-16bit-6451-p.asp I think these are the cheapest ones at the moment. Not sure how taxing and customs will affect the prices for a Texas buyer though.

If you need 56.2mm and have 2mm filters, you need 56.9mm so i think you have it set up correctly. But in practice the 56.2mm stated by the flattener manufacturer wont be exactly that, nor will your extenders and shims be exactly the length they say they are, like for example an OAG might be 19.05mm instead of 19mm in optical length, a 10mm extender may be 9.95mm and so on. Best prepare and get a bag of shims of various sizes (if you dont have already) and spend a couple of nights fiddling with the kit. I dont know how much difference there is in refractor correctors and newtonian ones, but so far of the 2 newtonian correctors i have tried so far neither were best at the stated backfocus.

My travel setup consists of: AZ-EQ6, steel tripod, 2x5kg counterweights, 8" newtonian, imaging kit including mini-pc, camera, OAG, all the cables (and spares) flat panel and a mobile power station to run everything. Because its not bulky enough i haul a 90mm refractor, AZ5, and eyepieces for visual to keep me busy while the imaging rig does its thing. I do this every time i use the kit as i have no backyard to image from. I typically take no longer than 30 minutes to have everything setup, polar aligned and guide calibrated. If you practice packing your gear the same way every time and setting it up the same way every time youll find that its not that difficult to do in about 30min or even less with a frac! I dont carry the original boxes, they are just way too bulky, would advice to find more travelable bags. See if you can find Oklop bags for your kit, they make all sorts of rugged bags for astro stuff. You might even find one that fits your esprit with the camera stuff attached so that there is less to setup. The EQ6 travels in any sports equipment bag easily (not comfortably though).

This one: https://www.firstlightoptics.com/sky-watcher-mount-accessories/lynx-astro-ftdi-eqdir-usb-adapter-for-sky-watcher-eq5-pro-heq5-syntrek-pro-az-eq5-gt-az-eq6-gt-and-eq8-mounts.html

Okay i am definitely weird then, my idea of a perfect broadband image is a boring one that doesnt stick out of the crowd too much, almost like a snapshot from some professional sky survey, and im okay with having seen that image posted by someone else before me (and after me). I do think an image can be "real", especially if compared to an image that is comparatively not real, i choose to die on this hill! So that the thread is not further derailed from the subject of stars to summarize my rant(s): Stars should not disappear, or cover the subject entirely and they should be sufficiently coloured to easily see that there are different types of stars.

Important to note that certain equipment doesnt like even 12v and the supply really should be at 13.6v (EQ mounts at high load and cold temps one of them). And temperatures greatly affect how long even a good quality unregulated battery solution lasts. In sub zero temperatures you can expect 0-30min of trouble free power and at 3 hours of use you can expect to recycle the whole thing. Just something for OP to consider as its not as easy and applicable to every situatuon as it seems (bulkiness is another negative too).

For image processing, and future proofing in general i think you might be better off saving some money for now and building a desktop PC from components later. You get a lot more bang for your buck compared to a mini format PC. But if you want that mini-pc anyway, CPU benchmark tests would indicate the mini-pc you linked to be about 3-4x faster in the CPU department alone. Wont translate into the same processing power increase butvshould be better still.