WolfieGlos

I first tried this one a year ago when learning the hobby, manually located it and framed it (it took over an hour to find it on a tracker by star hopping...all before I knew of plate solving!) and then only to find 3.5 hours of out-of-focus subs...so I had to remedy that mistake ! Anyway, here is my first "proper" attempt at the California Nebula imaged on 26th and 27th Feb, and 10th March with a large break due to poor weather. Canon 800D (modded) + l-enhance, ISO-400. 120 x 300s subs (10:00:00) 30 flats+50 bias. Processed in Siril, Starnet, AstrodenoisePy and GIMP. I may decide to go back and add some RGB stars, they just look nicer than pure white ones from the filter, but the forecast for 2 weeks is terrible. Comments welcome. Hope you like

I'm just over a year into AP and I also use a Canon 800d. I assume by RT you mean Raw Therapee? It's not something I use personally, I use Canon's own DPP software to check each raw file for clouds, star trailing, etc, before stacking. I did initially start out using only GIMP to process but I quickly found Siril was capable of producing better images and quicker. I now stack and process in Siril. I then also use GIMP for fine tuning and layers (i.e. if using Starnet for separate star processing) and lately AstroDeNoisePY. These are all free to use software.

AstroDenoise I’ve only just started using and I found the same regarding colour, but also brightness. It took me a while before I started changing the STF sliders at the top to realise that these were stretching the image, so I brought them both right down. I used this for my recent HorseHead image. Seems obvious to me now! I’ve since found that you can untick the “Normalise” box at the top which greys these out and prevents any stretching, and I then try it with 0.9 denoise. I usually change the tiling to 4 (no idea what it does; there’s no help that I can find, but I have noticed a small difference zoomed right in), but I also run several versions with varying degrees of noise reduction, down to about 0.6, and see which I prefer. The results can look quite “plasticky” so I try not to take it too far. I’ve used it at the end of my non-linear processing. As for Siril, I’ve tried the new noise reduction in the beta but I haven’t been that impressed with the results. In their defence they have said it works better on mono images. I forget their names, but the second noise reduction option took 30minutes to run on my system, and it looked no different to the first one! I’d be interested to see what result you get though.

Thank you 😀 Nope, I didn't use a filter for this one.

Thanks 😀 Canon 77D + EFS 10-18 lens at 10mm. I do begrudge the washing line in the middle though 🤣

Single 20s shot with the rig in action last night aiming at the California Nebula. Set up on my new (second hand) HEQ5 thanks to SGL @ThadeusB with some of the Aurora visible down here in Gloucestershire. The red streaks were just visible at the peak, the green less so but it was very bright on the horizon and noticable through that cloud....which didn't disappear all night sadly.

Possibly a bit late in the season for this one, I was hoping to get more time for the dusty areas, but the cloudy nights and now the Moon phase have ruined any chance of that. Anyway, here is a first attempt at M45, imaged across 2 nights 20th and 23rd Feb, 2.5 hours each before the target got too low. ISO-400, Stock Canon 77D + SW 72ED. 60x 300s (05:00:00) + 50 flats and biases. I think the longer subs may have blown out the stars a bit, but I like how they emphasise the brighter stars that are visible to the eye. Stacked in Siril, processed in Siril, Starnet and GIMP.

Superb image. Who said pigs can’t fly 🤣

Agreed, prefer the second version. Great result, especially the core 🙂

Yeah, that’s the same reason I didn’t want to modify my 77D so I bought a modded 800d. It made sense for me as both cameras have the same digic 7 processor, the same battery (important!) and sensor size. I believe if you modify it yourself and it goes wrong the camera cannot be fixed, I didn’t want to risk it but others have done it successfully 🙂

Thanks all 🙂 With the rosette in a similar area in the sky, I'm almost loathed to try it after what I had to do for this one! But kudos for going for it between your obstacles too 👍

Regarding satellites or aircraft, that's interesting as I've never scrapped a frame with them passing overhead! I don't understand the whole process about how they get removed in stacking (I should probably read up on it a bit more!), but I never get any trails left in my images. The only ones I do scrap, is when you get the large plume left behind a plane that slowly dissipates, essentially like a cloud. I also use Siril and Gimp. Regarding the camera, it's not that it's not up to the job, it's just not very sensitive to those wavelengths of light so will require a lot more time to bring it out. It'll be fine for galaxies and reflection nebula, less so for emission nebula. I didn't want to modify my camera, so I got mine from astronomiser. This page on his website http://www.astronomiser.co.uk/intro.htm shows a graph, and for the camera in question (a Canon 350), it is only circa 20% sensitive to that light. By modding the camera, it becomes circa 90% sensitive. This was mine with a stock Canon 77D, Evostar 72ED, ISO 1600, 67 x 120s (bortle 4). Really? How does this work, as I thought more time = more signal and less noise? Do you have to increase the ISO to do this? I guess the DSLR shutter count would go through the roof 🤣

I imaged this one last year with a stock Canon 77D, and I got a very similar result (but using flats) and was disappointed. The stock camera is just not sensitive enough to the Ha in emission nebula. I was also advised not to use a lenhance/extreme filter with a stock camera, only a modded camera. I haven't tried myself so others may shoot me down on this.....

I know, I know....yet another horsehead image! A difficult target for me, this is my first attempt at this area, and I imaged across no less than 11 evenings! I have a north facing garden, so to image this I have to set up in my narrow side entrance (which is by a road), wait until Orion passes a tree (circa 7pm), and then image for no more than 2 hours until I hit a glaring streetlight (on the other side of that road) which kills off any data I can hope to gather. To put this in perspective, using ISO-400 with the lenhance filter.....I can image for 240s at the start of the session (with frames gradually getting brighter), down to 60s by the streetlight (and a total washout)....but 600s if I'm in the backgarden on a different target facing north or up at the zenith. I hate that streetlight !!🤬 Details: Canon 800D (modded) + Evostar 72ED on a HEQ5 + belt mod. Guided in phd2, captured with APT. Stack of ISO-400, 139x240s (lenhance) + stack of ISO-400 124x90s (no filter) for a total of 12:22:00. Two images attached, first with my Siril+GIMP edit and a second where I have ran it though AstroDeNoisePY. First time using this (free!) denoiser, it took several tries to get a decent result as it produces an image that, to me, seems a little "plastic-y".... so I overlayed the original non de-noised image at 15% on a screen mode to add a little back in 😄🤣 But actually, all considered...quite happy with the result. Feedback welcome 🙂

I managed to image on Monday evening with that pesky Full Moon, in an attempt to capture Comets C/2022 E3 (ZTF) and C/2022 U2 (Atlas) near to Almaaz in Auriga (bright star bottom left). But Comet processing is new to me, this is the first comet image I've taken...and I jumped in at the deep end with two of them! I think a lot of people at the minute are trying to learn the processing, and getting a sharp star background and comet is proving challenging. Deep sky stacker just doesn't ever give me a usable result on any of the 3 settings. But I managed to get a decent result with Siril, just following their tutorial. Below is a screengrab where I've stacked the stars, Comet 2022 E3 and C2022 U2 separately in Siril, run a basic asinh and auto histogram on each in Siril, and then overlayed them in GIMP. No other processing. If I could only figure out how to remove the star trails from the comet images I would be much happier with it, but if not, I'll stick to the star trailing image. I'm hoping to process this a bit more and see if I can get the tail to show up (it's there but very faint, think it's the Moon effect...). Canon 77D, 64 x 90s at ISO-400. 50x flats and bias, 9x darks. Version below with sharp stars, and the stack on just C2022 E3 ZTF, which also shows Atlas. Comments and assistance welcome 🙂

Thank you 🙂 Currently on my iPad too and I agree, there is a greener cast on the right side of the image. Didn’t notice that, if I recall that’s the side that had more LP, will definitely take a look at it.

Thanks for the input all. Well, I've had a few more attempts at processing thanks to the input of everyone, and this is the best I have come up with using Siril and GIMP. I've had to do several more steps compared to most, partly as I was being a bit more careful with the steps, but noise levels remain the biggest detractor when zooming in, however I feel this is definitely a step forward compared to what I had before. Without PI the only way I seem to be able to reduce noise effectively is more subs ! GIMP's noise reduction always destroys the stars when I use it, even masking them leaves them looking somewhat fake against the background with the overlap between them. But the only way I could bring out this level of blue in the galaxy was a separate layer with a blue curve adjustment, and then mask and brush it. If I applied it to the whole image, it looked very cold and the blue star halos were too obvious. Comments / observations / criticisms welcome 🙂 Siril: Crop (x=259, y=0, w=5363, h=3579) Background extraction (Correction: Subtraction) Photometric CC SCNR (type=1, amount=1.00, preserve=true) Asinh Transformation: (stretch=1000.0, bp=0.00000) Histogram Transf. (mid=0.035, lo=0.332, hi=1.000) Generalised Hyperbolic Transformation Saturation enhancement (GLOBAL amount=0.5) Cosmetic Correction Deconv. (iter=1, sig=1.522) Saturation enhancement (RED amount=0.42) -- EXPORT TO GIMP New layer with sharpen + contrast boost. Mask and brush to core. New from Visible. S-curve. Colour select for background "green noise". Noise reduction 7 and de-saturate. Darken shadows. New layer for contrast boost to core, mask and brush. New from visible. Darken levels. New layer. Increase blue curve, mask and brush to spirals.

Wow, that was from my fits file ?! 👏 Thanks for taking the time to do this as well Tomato, the detail you've pulled out of it combined with the lack of noise I'm really quite surprised by! I agree it's a nice level of blue, fairly subtle but obvious too. Further to my last post....definitely considering PI for the Blur and Noise Xterminator I've seen so much posted about lately. One thing I've taken from this thread is that I thought I was getting the hang of processing....clearly I've still much to learn 😵

That's a very good point on the order of PCC/BE , noted - thanks. There is a noise reduction filter built into GIMP but it's quite limited and I find it usually destroys the stars and doesn't do a very good job, still leaving visible noise just less of it. I haven't paid for any software yet and that's probably holding me back in the final image quality. I did try a free de-noising program once, AstroDenoisePY, but it gave very poor results when I tried it.

Thanks very much I was nearly going to get a 6D or 600D, but the reason I purchased the 800D was that it was a near match for my 77D which I already owned. They have the same battery (helpful!) and similar dynamic range/ISO/read noise results on photons to photos. Stars...love em or hate em!

Wow, thanks all ! Thanks for the detailed input and critique, much appreciated Yep, that's pretty much how I pictured it based on viewing other peoples work and considering the equipment I'm using. For a quick pass, that's really great! Sorry if this sounds silly, but what is binning the image x2? Is this a drizzle? I do have ASTAP but haven't used it for anything other than a quick mosaic trial and tilt checking (which I continually suffer from...but that's a different topic). The Siril workflow is one I picked up somewhere a while back, it may have been here or on cloudynights before I joined any forums, and it's generally been OK but I do adapt it to suit what I have. That one was: Crop/Photo CC/BE/Deconv/Asinh/Histogram/Deconv/Saturation/SCNR. That one recommended Asinh +300, and then tweaking the black point until the point before the level slider reached 0 to avoid clipping. Did you adjust the black point at this stage? I think I will give +1000 a go and see what it does. I thought SCNR was always required to remove the green cast, so again interesting that you didn't need to use it. Deconvolution I generally don't use and I trial it each time I have an image, but this is one of the few times I ended up keeping the result. Using different values, the first run reduces star sizes and brightnesses (and also highlights, so I used GHT to try and bring them back...which now sounds silly...), and the second run sharpens the stars. Similarly, the banding reduction I rarely use but it seemed to make a difference here when I viewed it in Histogram mode in Siril. I can't believe I'm saying this again...but CLAHE I also rarely use!! Usually I adjust curves in GIMP and apply contrast this way. The median filter, I'm not sure what it is actually supposed to do, but I find it reduces noise and without PS or PI I am currently very limited noise reducing options. I won't get a chance tonight or tomorrow, selfishly it's the wife's birthday, but I will take another shot at this on the weekend when I get a chance.

Hi Onikkinen, So the camera has been modified by Astronomiser to remove the rear UV/IR filter. Sorry I wasn't clear above, what I meant was that I was not using another type of clip-in or 2" filter, i.e. light pollution, dual/triband, etc. I live in a bortle 4 area, so skies are pretty good. M31 and M33 are the only times I've used the 800Da for galaxies, and I decided to use it for M33 to try and capture some of the Ha. I've never imaged it before, and the last time I imaged M31 was a year ago when I was first getting into the hobby with a 77D and a 300mm lens, and even then I didn't get the blues...although that was processed in GIMP with a very limited knowledge of processing at the time. I do still have the stock 77D, which is useful as both cameras have the same size sensor. I have attached the linear stack straight from Siril, with no processing if anyone would be kind enough to take a look 🙂 It will need cropping as you will see my framing wasn't perfect over the few nights I gathered the subs.... My workflow was as follows: Photometric CC Crop (x=97, y=0, w=5372, h=3585) Canon Banding Reduction (amount=1.00) Background extraction (Correction: Subtraction) Deconv. (iter=100, sig=0.400) Asinh Transformation: (stretch= 300.0, bp=0.00375) Histogram Transf. (mid=0.261, lo=0.036, hi=1.000) -- EXPORT TO STARNET V2, RELOAD STARLESS IMAGE Generalised Hyperbolic Transformation (SF=1.313, LSI=1.592, SP=0.10219, BP=0.06425) Deconv. (iter=1, sig=2.000) Saturation enhancement (amount=0.20) SCNR (type=0, amount=1.00, preserve=true) Cosmetic Correction Median Filter (filter=3x3 px) CLAHE (size=16, clip=1.00) Sharpening added to core in GIMP using masks, stars overlaid. m33_result.fit

A few weeks ago we had clear skies every night for 5 days, which was great as I recently upgraded from a star adventurer to a HEQ5 and this was the first time it was used…and bar a few polar scope calibration issues it worked flawlessly 😀 Using a Canon 800d (modded) + Evostar 72ED and no filters, I pulled in 85 x 240s subs on M33, dithered every 5 frames using APT and stacked with 50 bias, 60 flats and 8 darks in SiriL. After stacking and processing in SiriL, Starnet and GIMP, attached is the best version that I could produce, and I’m fairly happy with it…aside from wanting more subs…! However I have seen some great images on this forum recently of M33 where the galaxy has a blue cast to it, which now makes me doubt at what I’ve produced. After many different processing attempts M33 always comes out grey with a yellow core. I’ve tried it with/without photometric colour calibration and background extraction but the same resulting colour comes out every time. I also had a similar result with M31, and I didn’t question it, but now I’m thinking is it something I’m doing wrong?

I have just upgraded to the HEQ5 and have been using it for the first time this week, and I have exactly the same equipment as you other than I have a canon 800d. Same county too oddly! I too had to set the RA and DEC rates high, I set them both to 0.9 and phd2 worked immediately. Mine runs very smoothly, no subs scrapped all week from trailing, a mixture of 90 and 240s exposures. Was the guiding stability due to just the decking movement? Mine has only varied on two occasions; when the mount got to the meridian and stopped, and whilst dithering.

Snap, I also used my HEQ5 for the first time last night !! It's certainly a step up from the Star adventurer. Great start on M42! More time will allow you to stretch it further and get the outer core, I grabbed a 2.5 hours under full Moon a few weeks back with an lenhance. Oh, and another vote for SiriL too.