ONIKKINEN

Some videos of the light show we just had. Taken with a Google Pixel 7 in astrophotography time lapse mode from southern Finland at around 60 degrees of latitude. First one is towards Orion, 4 minutes worth. PXL_20240303_182029622.NIGHT.mp4 Next one towards the Pleiades, also 4 minutes. PXL_20240303_183039778.NIGHT.mp4 Then the best one, 5x 4 minute timelapse stitched together. Towards north this time, where most of the show was going on. MOVIE.mp4 Not sure the videos will look nice in forum format, might need to click to full screen and let them be scaled to your display - let me know if there is a better way to upload. Couldn't figure out a (free and easy) way to stitch the videos together for the last one without a loss in resolution so this is just a google photo autogenerated "video highlight" which reduced the resolution but i think it still looks ok. Gotta say i am very impressed with the Pixel 7 and the automatic astrophotography mode. Really there is no trial and error involved, just stabilize the phone somehow and click go and it will do its thing for 4 minutes and spit out a stacked image and a video of the frames that went into it. The stacked images dont really work for Aurora in this case, since these ones moved really fast so no point in stacking all that movement to a single image.

Naked eye was just green here, some photographic red but not much and not for long.

Bright Aurora here in southern Finland. These were pretty strong, i wonder if UK observers got a chance to see some as well? Its cloudy now though, but was good while it lasted.

To register the images to each other, first drag and drop both of the stacks into the "Conversion" tab in Siril. Give the sequence a name and then press the Convert button, this creates a sequence with just those 2 files. Here you have to have them in the same format, so both in RGB with no channel extractions or anything like that. Then in the Registration tab choose the "Global star alignment" as your registration method and hit Go register, now they are as well aligned as they can be. You can choose which of the 2 stacks is the reference frame by having that as the first frame you input into the Conversion tab. If you want to align the Duoband to RGB, then drop the RGB image first or vice versa if you want to use the framing of your Duoband image.

Quote from the site: Cant say i like that. To my eyes this looks like a VX scope with a new coat of paint, and a new focuser (which is a welcome addition, if better than the VX one that is). The aluminium tube in the VX series is quite frankly awful, and i will argue the worst component of the scope so if this is the same tube with another coat of paint then its not "ideal" (sorry, had to). Also looking at the pictures posted on the site the mirror cell appears to be very similar to the VX cell, differing only in the way its attached to the tube (VX is held from the side with 3 screws with the mirror cell being completely inside the tube, this appears to be screwed to the back - otherwise, the actual mirror holding part looks the same). The flimsy and narrowly spaced tube rings are also the same as in the VX scopes. So just the focuser is brand new then? I will be cynical and say that this seems like an attempt at re-marketing the generally not well received VX series.

Siril doesn't have an easy way to mix narrowband data to RGB, i would strongly recommend doing this in another "general" image processing software like Gimp or Photoshop. It will be significantly easier to get a result you like that way. If you absolutely must use Siril then there are a few available methods, all of which are compromises to some degree. The easiest way is what you were thinking of already: Stacking the stacks. Simply register the narrowband RGB stacked image to the broadband stacked RGB image and stack with average and no rejection. This result will make your broadband portion of the image worse than in just the broadband stack, and your narrowband portion of the image worse than in just the narrowband stack - so you get the best of neither but at least they are combined to an image now. You may try stacking with weighting set to "number of stars", which will give the broadband stack a much higher priority because it likely has a much higher star count. The other method involves using the Pixelmath tool to combine the extracted channels in some way which you will then recompose into an RGB image. The Ha to red part is not too difficult, you can just mix red and Ha with the max(x,y) operator for example, which will take the maximum pixel values from both and combine them to an image - which will add the Ha intensive parts of the image to the RGB red, but also add all of the noise. The Pixel math way rarely produces exactly the image you want it to, and even then it will take a great deal of trial and error. The compromise stack the stacks method is easy, but you wont get everything out of either dataset that way. In short, i recommend Gimp/Photoshop for blending the stacks.

Hey, thanks for the tip. This looks really good, has all the features you'd need and it can expose for 17s which is pretty good already. Should be ok at f/1.9 in an SQM 20.8 ish location that im planning to visit.

8310 milliseconds seems to be the max exposure used by the 24mm equivalent lens that APIs can access, including OpenLiveStacker. Tried the evaluation version of Proshot as well, which can only fully access the 24mm lens, and at 8s exposure. The 2x zoom or 48mm equivalent lens in the phone does say it could go 30s according to the hardware scan in Proshot, but i cant actually set it to that. Seems like a hard limit set by Google rather than app limitations.

Old phone stopped accepting a charge, probably just the USB-C port that needs replacing but went ahead and purchased a new phone anyway - the Google Pixel 7. I'm thinking i will try to do some astrophotography with it as the camera seems to have decent low light performance, and has a built in astrophotography mode where the phone stacks an image by itself. I will also try manual exposures and do stacking "normally" on a computer to see how that goes but not sure what the best app for that is. So the question is, are there any decent third party apps to utilize the camera in full manual control where everything can be adjusted as i please - same way one would use a DSLR in manual mode? Already tried Open camera, which does give manual exposure and ISO control with optional manual focus that can be locked in place, the app also supports repeated exposures which is a must so that i dont have to press the shutter every time. Can also turn off all the noise reduction features and get raw .DNG images out, so in theory it should do nicely. The app will only let me expose for 8.3 seconds though, not sure if this is an app limitation or a hard limit on the camera itself. I was thinking of MacGyvering some kind of contraption to piggyback the phone on my AZ-EQ6 while its doing its thing with my 8'' newtonian, so longer exposures would be preferable.

I've no complaints for my one Antlia filter, and neither do i have any for my 3 Baader filters - should say none of them are these 2. Antlia filters are usually received well in terms of quality, maybe this is just a better deal than the Baader?

At what point does nebula imaging become galaxy imaging? If we look outside the milky way then almost every nebula is a part of some other galaxy rather than an isolated target. For targets of appreciable size the magellanic clouds would fit the nebula imaging criteria, the Tarantula nebula region in particular. Cant do that from Europe though. M33 is a good one, with some focal length you could argue its more nebula imaging than galaxy imaging.

This is the case for me as well. I am always driving to a location rather than setting up at home, so knowing what to expect there is important.

I think the mount is aware of the RA worm gear position, there is a small notch in a washer attached to the end of the worm gear, which is read by a sensor when the notch rotates over it. I have not used EQMODs PPEC, but from a mechanical point of view i think this is how the mount knows what part of the cycle the gear is in. So as long as you dont go and rotate this system manually somehow (impossible without dismantling the mount) it should be ok. Could be wrong though, someone who uses PPEC might have more info on that. There is another option to periodic error correction, and one that will require no extra work or recording of the error. That would be the Predictive PEC algorithm in PHD2. This will record the periodic error as you guide, and gets increasingly more accurate the more you run the mount. This data is gathered directly from guiding performance, so i think has a chance to be more accurate, and i can confirm it works really well with my AZ-EQ6 that has a very aggressive peak twice per worm cycle. It does take a while to get accurate, about a few cycles worth of guiding per night. But chances are your early night data is not perfect anyway due to the scope still cooling down (if you set up fresh with the scope indoors before use), so there are no practical losses per night when using this. Not sure if the prediction data stays between nights when using the same calibration, as i recalibrate each night.

My whole imaging rig, including camera and mini-pc has been rained on twice now. The mini-pc seemed particularly bad since it has vent holes on the top, which is basically a direct route for water to find its way to the motherboard. I did the rice thing for the PC, but not sure it actually did anything other than give me some peace of mind. Its been more than a year since the last water incident and everything still works. Maybe i got lucky, or maybe a slight drizzle on electronics is not so catastrophic, in any case just dry everything as best you can and dont power anything up until you are certain things have dried down.

+1 vote the camera under the OTA advice, really no downsides to doing that. Easier to balance the system since the rather heavy imaging train is now closer to the center of mass. Could make a noticeable difference if stability is suspect.

The typical advice for an "ideal" focal ratio for lucky imaging is in the range of pixel size in microns x 4-6. So for your f/10 scope, i think a 2 micron pixel camera like the 678MC would do nicely without a barlow. You can image the Moon in RGB too, it just takes some effort in the colour processing part to make an image where the colours are nice and balanced enough to look at. With mono you can use filters like a solar continuum or an IR pass filter, so some choices to be made on what you really want. Although many OSC cameras also have decent sensitivity in IR so you can also use the IR pass filter with a colour camera to get a monochrome image - likewise with the solar continuum filter, although now only half the pixels are doing any work so half the sensitivity.

I've managed to not make any new purchases in what, maybe a year? Before that, since 2020 when i started i had a package at the parcel locker every month, or so it seemed. It helps that I'm broke at the moment, think i would be making purchases if that were not the case. I think i am fairly content with what i have now, and there are no major "need to have" type purchases lined up. Imaging rig works, so no point in trying to change things up, and my visual scope and binoculars give me views that satisfy that itch. Poor weather definitely gives too much time to do some window shopping rather than actual time under the stars, can relate to that.

Just how long is your adapter train, can you grab a picture of the setup with the camera attached?

I have the old version the River 2 replaced: The river 300. The River 300 has some longevity issues, which ive barely started noticing now 3 years in so not a deal breaker - but apparently the new one has different battery chemistry, and different "native" voltage ( River 300 is 28v, River 2 is i think 12.6v). So cant say what the new one is like, but can say that my River 300 has exceeded expectations, so i have confidence in Ecoflow as a brand.

I do mobile imaging only, by traveling to a darker location just under an hour away so there are always time losses to setting up and just getting there and back. The average night is somewhere around 50% efficient, with my best and longest nights probably not more than 70% - by this efficiency i mean i leave home at 23:00, return and finish post night maintenance (drying things, recharging batteries and such) by 07:00 and of those 8 hours spent working only 4 get put into a stack. I dont really get many surprises or other new technical issues with kit, but the basic operations just take time.

This is what i would do if i were the OP. Manual stacking ensures you get the best image out of the hard work spent capturing the data. Siril is very close to being SSD write speed limited for registration and image analysis, at least on my system. My biggest stack was 1519 subs at 300mb each, to a total of 455gb and took a few hours, but not as long as 4. With an old HDD some stacks might take a while, but shouldnt ever run into multi-hour stacking ordeals with modern PCs.

Yup, a shadow from a mote of dust. Most likely on the sensor window, or if you have a filter somewhere close to the sensor then on that. Flats are the cure.

17 billion solar masses, 500 trillion times the sun's luminosity, 7 light year accretion disk, eating one solar mass of matter every day. The numbers are so crazy it hardly makes any sense! What an unimaginable beast. Thanks for posting, very interesting.

The best place on the internet for discussion related to the hobby i would say. I dont actually recall a case where a question or issue i had with kit or something else was not resolved, or an answer could not be found. I never planned on posting frequently when i joined (no idea where that post count came from!), it just kind of happened. Safe to say i like it here. Also want to say that i greatly appreciate the likes of @vlaiv and everyone else who offer their detailed explanations of even the most obscure subjects in discussion here, and for free! Almost everything i know of astrophotography was learned here, tip of the hat for everyone who fuels the learning by posting here.

I was thinking more about things we cant help, like a gust of wind which will now scrap 18 minutes of data instead of 2. Agree with your reasoning with the other things though, there is no difference in a 3 minute or 30 minute guide duration if we dont have external disturbances. Getting quickly off topic now though.