ramdom

Nope, not mine but thanks. I've only finished the Squid but not the entire thing yet. I'm struggling with combining exposures of different lengths (153 x 5 minutes and 204 x 7 minutes for Ha) to get the maximum SNR. I experimented with a bunch of options using 1/4 the data and here's a sample image with 1/4 data as to what the final image will look like: http://ram.org/images/space/downloads/Image40.jpg and you'd think the same parametres and choices that worked well for 1/4 data would continue to work well for 100% of the data but no, the whole thing has collapsed. Previously I was able to use GHDRComposition to produce seamless integrations with high SNR and now it just isn't working anymore. So I'm still playing at different ways of skinning the cat until I get something I'm satisfied with... --Ram

Thanks, the Bat is coming - I have a ton of data but working to integrate exposures of different lengths (7 minutes vs. 5). --Ram

Stunning image! --Ram

Also includes: v419 Cephei. Total integration: 3280 minutes/~55 hours (*632 x 300s for O3 + **60 x 120s for OSC). Cameras: *QHY163M (16mp mono) and **QHY247C (24mp OSC) CMOS cooled to -20 and -15 degrees C. Telescopes: *Takahashi FC100DF Steinheil fluorite doublet and **Stellarvue SV70T triplet apochromat refractors @ f/4.9 and @ f/4.8. Reducers: *Takahashi FC-35 (0.66x) and SFFR70-APO (0.8x). Mount: Paramount MyT. Filters: 1.25" Astrodon 5nm Ha, 3nm O3, 3nm S2 and **2" Baader UV-IR-Cut Software: TheSkyX Pro, Sharpcap, PixInsight. Inline images with reduced quality uploaded to the forum. Full resolution images of all versions are available at https://www.astrobin.com/jdaa90/ and of the primary image at http://ram.org/images/space/scope/1.4+7.4.5+6/ou4_c_orgb_632x300+60x120_3280m_55h.jpg The Squid nebula (ou4) occupies over one degree of the night sky, representing the largest angular extent ever found in a planetary nebula. Known colloquially as the giant squid nebula, it is physically nearly 50 light years across. This bipolar nebula could be one of the nearest of its type known, though its possible planetary nebula nature needs confirmation. Even though it is big and close, you're not likely to find it easily. It is an extremely faint nebula emitting primarily O3 signal and resides within the larger Flying Bat nebula (not shown here, yet) which tends to overshadow it, making it a challenging target to image. The nebula is created by the outflow of material driven by a triple system of hot, massive stars catalogued as HR8119 (blue hypergiant) as well as the pulsating variable star v419 Cephei (red supergiant) seen near the center. While their shapes do their names justice, to me, the Squid seated within the Flying Bat more resembles a hand holding an infinity stone (viewed sideways). This is the first image of my Flying Bat and Squid project/series, which became a huge undertaking for me, ending up with a total of more than 131 hours in the final integrated widefield image of both objects and a series of three main images with a few versions of each depending on the data set used for the integration. In the first image, I am showcasing the Squid nebula by itself using only the O3 filter data, with and without RGB stars. The mono Squid imaged with the Takahashi FC100DF consists of ~53 hours of total exposure in O3, making it my single longest total exposure of a target with a particular framing with a specific filter/scope/camera combination. The RGB data collected using the QHY247C with the SV70T adds another two hours to the exposure. The total integration for the version with RGB stars is ~55 hours. I also captured another 5.5 hours of O3 data using my SV70T which is present in the final image in the series but I haven't created a separate Squid only version with that integration yet but I might if I get around to it. There are six versions of the Squid only framing at https://www.astrobin.com/jdaa90/ --- the difference between the two monochrome versions of the Squid is the application of HDR Multiscale Transform which reduces the halo on the central star as well as the amount of data used: (A) is based on the full ~53 hours whereas (B) is based on the best 40 hours. (C) and (D) are corresponding versions that combine O3 in the blue channel with RGB stars along with changes in the amount of saturation and brightness. Similarly with (E) and (F), but the Squid is in monochrome mixed with the RGB stars background. After doing different versions of the Squid by itself, I worked on a narrowfield and widefield versions where it is situated between the wingspan of Flying Bat (coming soon). I started with data from the FC100DF/QHY163M combination which results in a total exposure of 78+ hours for SHO. The SV70T/QHY163M data used for the widefield framing representing another 51+ hours was also integrated in. The RGB data using the QHY247C with the SV70T adds another two hours. The total exposure of the final image with the narrowfield or widefield framing is 131+ hours, my longest to date! As always, thanks for looking! --Ram

This is an amazing image - the best M101 I've seen... --Ram

Also includes: Cr30/Mel16/IC1824/NGC1027, IC1831, LBN646-48,50,55-57, and LDN1356,59-73. Total integration: 43.75 hours/2625 minutes (136x7m = ~16h for Ha + 92x7m = ~11h for O3 + 147x7m = ~17h for S2). Camera: QHY163M (16mp mono) CMOS cooled to -15 degrees C. Telescope: Stellarvue SV70T triplet apochromat refractor @ f/4.8. Reducer: SFFR70-APO Mount: Paramount MyT. Filters: Astrodon 5nm Ha, 3nm O3, 3nm S2. Software: TheSkyX Pro, SharpCap, PixInsight. Inline image with reduced quality uploaded to the forum. Full resolution images of all versions are available at https://www.astrobin.com/97h2mp/ and of the primary version at http://ram.org/images/space/scope/1.4.4.5/ic1805_136x420+92x420+147x420_2625m_43.8h.jpg The Heart nebula region is about 7500 light years away from Earth in the constellation Cassiopeia. The 330 light year diametre complex contains the eponymous emission nebula (Ced7/Cr26/IC1805/LBN654/Mel15/Sh2-190) shaped correspondingly, along with a separate region labelled the Fishhead nebula (Ced6/IC1795/LBN645/NGC896), which was the first part to be discovered. The nebula's shape and distinct signal is due to a cluster of stars in the middle in an area that could appropriately be called the tendrils of creation. One of the more striking aspects of this nebulosity is the number of dark nebulae (~15) contained within it (LDN1356 and LDN1359 through LDN1373) many of which I've tried to highlight especially on the Ha only image. There's also a small open cluster to the right (Cr30/Mel16/IC1824/NGC1027). One of the cooler features is the ring nebulosity in the centre which you can make out if you look closely, which is like a second (or more likely separate) shell of gases being pushed out. This capture is part of my "make up for being a newbie" series, where usually once a year I revisit one of my very first images and redo it with the latest capturing and processing techniques that I've learnt. In this regard, the Heart nebula complex represented a lot of firsts for me: it was one of my very first astrophotography images, my first narrowband image, the first colour image with the SV70T scope, and it was done on my first mount. This version which I did back in 2017 had a total of integration of 4.7 hours, so this current version has almost ten times as much information going into it. I hope you'll agree with me that this current version is a far cry from the image I did using live stacking, 8 bit PNGs, and my AVX where I could only get two minutes unguided per frame, yielding a total integration of less than five hours (https://www.astrobin.com/305156/). There's ~44 hours of captured data going in this version and I think even though the gains are incremental, I was able to bring out additional background nebulosity and details, as well as reduce noise, particularly in the Ha only image which I thought turned out really good: deconvolution actually worked like I thought it would for the first time and I was able to achieve a balance between sharpening and noise reduction. When I first started redoing this, the moon was half full so I decided to capture S2 data first and I was off a bit in my framing which I only corrected after my first session (there's a seam barely visible if you can spot it). I was able to use it but it is why I have the most amount of data using this filter since I wasn't sure if the first session would be useable in the end. Overall, I would have to say this is the first image where everything came together nicely in terms of processing. Take for example the ring nebulosity, it's missed in many images of this target or not pronounced (my previous image doesn't have it at all) but it shows up here nicely. I've put up two bicolour and tricolour Hubble palette versions of this capture on AstroBin along with the Ha only version. Previously I had done a HOS combination but that was mostly Ha data since I had done a crappy job on the O3 and S2 data; this time the colours in the HOS were okay but not as good as the SHO version so it is not being showcased (just imagine the Ha only image in bright red and you get the picture). The framing is also the "right side up", looking at it from the Earth. As always, thanks for looking! --Ram

Yes, both the broadband (which will let most light in, just not ALL) and the duo narrowband filters (these are not the same as regular narrow band filters) will work on a unmodded DSLR (so can real NB filters but the issue with a DSLR IMO is cooling and in your case, a slightly older model). This is what I mean by the duo narrowband filter: https://www.cyclopsoptics.com/astronomy-filters/stc-astro-duo-narrowband-filter-48mm-2-free-shipping-free-lenspen-set/ It's a 2" model and it's expensive (about $300+) but I don't know the prices - this is just the first link. It says on there it's suitable for DSLRs and OSC cameras. So if you do get a OSC CMOS camera that can be cooled, you can still consider this down the road. Bortle 4 is good though - that's rural/suburban transition if I recall so you shouldn't be having that much issues with light pollution unless you're imaging with the full moon or have a light source. So it could be your processing - I'm just wondering why your images look a bit washed out. --Ram

What is your light pollution level (Bortle scale)? More time per exposure isn't necessarily good - it depends on your light pollution. If you are in a light polluted area, you may be better off with shorter exposures but more of them. The PacMan is a relatively bright object so you shouldn't need to spend too much time on it total. If you are in a light polluted area five minutes may be too long and one thing to look into is a broadband filter. Also I've seen some people use these so-called duo narrowband filters for colour cameras and they're producing really quality images with those - with most of the light pollution filtered out, these emission nebula will really shine through such filters. If you're imaging from a dark site then obviously your issue isn't light pollution, but I don't know much about your camera... --Ram

Total integration: 37 minutes/2210 seconds (37m L + 7-8m for RGBSHO). Cameras: *QHY163M (16mp mono) and **QHY247C (24mp OSC) CMOS cooled to -15 degrees C. Telescopes: *Takahashi FC100DF Steinheil fluorite doublet and **Stellarvue SV70T triplet apochromat refractors @ f/4.9 and @ f/4.8. Reducers: *Takahashi FC-35 (0.66x) and **SFFR70-APO (0.8x). Mount: Celestron AVX. Filters: 1.25" Astrodon 5nm Ha, 3nm O3, 3nm S2, Orion SkyGlow. Software: TheSkyX Pro, SharpCap, PixInsight. Inline LRGBSHO and LRGB images with reduced quality uploaded to the forum. Full sized versions of both these and the LRGB and L only images are available at https://www.astrobin.com/d5zk98/ Full sized versions of the LRGBSHO and LSHO images are also here: http://ram.org/images/space/scope/1.4+7.4.5+6/neowise_c_lrgbsho_37m.jpg and http://ram.org/images/space/scope/1.4+7.4.5+6/neowise_c_lsho_37m.jpg Comet NEOWISE aka C/2020 F3 (NEOWISE) was named after the mission that discovered it using the Wide-field Infrared Survey Telescope (WISE). Initially identified on March 27, 2020 when it was an eighteenth magnitude object, it started getting brighter and brighter as its long period approached the sun, eventually reaching a peak of magnitude 0.5. This is the brightest comet observed in the Northern Hemisphere since Hale-Bopp in 1997. I had earlier observed the comet with my naked eye a couple of times, once when it was closest to the sun on July 3. But the early morning of July 12 was when everything cooperated in terms of seeing/transparency/clouds and it was the brightest comet of any I've ever observed with my unaided eye. It was also my daughter Maya's first comet observation. The first time I had chance to image comet NEOWISE was on July 24, 2020 when it was around magnitude five just a day after its closest approach to Earth. The issues I was having were numerous: I was using my normal high end mount for a long imaging session of the Heart Nebula IC1805 (again!) and I didn't want to move it or change its synchronisation. There were low level clouds and this comet hugged the horizon whether you saw it in the morning facing Northeast or at night facing Northwest. I had also moved my cameras around and had forgotten the spacing required to obtain the roundest stars with my QHY247C which I didn't have time to debug. I finally dragged out my original Celestron AVX mount and moved it an optimal viewing location, mounted my FC100DF and SV70T scopes on it, and managed to grab some frames using two cameras. At first I was excited to go back to my old mount, doing something different, but then it was such a pain to use that I realised what a difference the MyT makes! In any event, I was committed now. I initially started with my FC100DF and used my Baader VariLock T-thread extender to adjust the spacing between the QHY247C and the reducer to get the stars as round as possible and grabbed several frames at 1s, 2s, and 15s. Then since I knew my SV70T was set up more correctly with the QHY163 (this combination is what I was using on a nightly basis to image the Heart), I decided to use that to capture several frames using just a luminance filter. Since the Ha, O3, and S2 filters were present in the filter wheel, I imaged several more frames to highlight whatever was being captured based on the bandpasses of these filters at 4s, 15s, and 30s. I would argue this is a fairly unique combination and in addition to seeing where these elements (or other substances that overlap these bandpasses) are highlighted, I wanted to get some colour into my mono images in case my OSC images didn't work out. I then prepared all the necessary darks, calibrated, registered, comet and star aligned, and integrated these frames separately and in combination using PixInsight. In terms of processing, I first created a luminance (L) master of only the comet that included all frames, including the narrowband data (I experimented with creating both a L-only master and a complete master). I then created separate OSC, Ha, O3, S2, R, G, and B comet masters (in part because I wanted to see/show the data separately). Since a comet moves much faster than the stars in the sky, and this was my first time processing comet data, I had a hard time with removing the star trails and getting clean comet only and stars only images: only the main LRGBSHO image (A) is the one where I carefully clone stamped out the star trails; in all other cases, I didn't bother since I should've done this earlier in the process. The solution that worked for me was to create a starless image of the star master created from aligning on the stars (as opposed to aligning on the comet, which are supposed to be done separately and combined but that didn't work for me; I even tried a star mask based approach to add in the stars but again, no luck) and then subtracting it from the parent image, leaving me with only the stars and without any comet signal. Armed with L and RGB stars only masters, I then used the SHO-AIP script to figure out which combinations looked the most aesthetically pleasing. Overall, given the timing, the time spent on capturing (less than an hour), the rush in which it was done, and the older AVX equipment, I thought it turned out okay. I rarely see people taking narrowband data of comets, so I thought that was interesting. You can see both tails in the narrowband only image (B) are mostly green indicating hydrogen signal but the comet head is purple indicating a combination of sulphur and oxygen and the gases right behind are cyan indicating some combination of hydrogen and oxygen. The LRGB image (C) on the other hand shows the typical green halo of comets that's due to the presence of carbon. There's some internal structure to the body (i.e., the actual ball of rock and ice is clearly distinguishable). Finally the different sets of images combine to make one that is clearly brighter/better in my opinion even though I have a soft spot for the narrowband only image. That said, having processed my very first comet, I do wish I had spent more time capturing additional data. I started my astronomy hobby in all seriousness after seeing Halley's comet in 1986, a time when I could barely tell the difference from a comet or a random star, even with my small 3" telescope. Fortunately I had much older people than me who were able to work magic with this scope and what I saw was pretty decent, especially compared to what I saw in a 16" homemade reflector (the construction of which was completely done by hand, from the cutting of the wood to build the tube, to the grinding and polishing of the mirrors; I never did this myself but I went to every class and watched a bunch of people do it and saw a bigger and more refined operation of the same process, i.e., a three metre mirror being automatically polished going by memory). So working with this comet was a fun trip down memory line and while these pictures are not as great as they could be due to the timing, I can't wait 6,800 years to see and image it again! As always, thanks for looking! --Ram

That is a stunning image! --Ram

I've now linked to the bigger sized images - so if you click on the small inline images it goes. Thanks for suggesting this! --Ram

You know, whenever I tried to upload something I can't get more than 10 MB - 1 GB for each forum post/image would be amazing but I think unrealistic. Because I wanted to upload two, it was easier to just upload the inline images. But glad you were able to get it - I think the astrobin or telescopius is the only place where you can get the multiple versions. I could put them up too but I've not figured out how organise them like they have. Thanks everyone for the kind words! --Ram

If you click on the JPEG link, it doesn't take you to my web page? Also you can go to AstroBin here and see all the different versions: https://www.astrobin.com/g20c4j/ The images aren't hot linked - just inline images I use on my web page (240x180 pixels). --Ram

Total integration: 60.4 hours/3625 minutes (263x5m = ~22h for Ha + 278x5m = ~23h for O3 + 184x5m = ~15h for S2). Also includes: WR-153/GP Cephei, RW Cephei. Camera: QHY163M (16mp mono) CMOS cooled to -15 degrees C. Telescope: Takahashi FC100DF Steinheil fluorite doublet apochromat refractor @ f/4.9. Reducer: Takahashi FC-35 2". Mount: Paramount MyT. Filters: Astrodon 5nm Ha, 3nm O3, 3nm S2. Software: Sharpcap, PixInsight. More detail and different versions are here: https://www.astrobin.com/g20c4j/ - inline images with reduced quality uploaded to forum. Full sized image of my first choice is at: http://ram.org/images/space/scope/1.7.4.5/sh2-132_184x300+263x300+278x300_3625m_60.4h.jpg The Lion Nebula is an extended emission nebula in the constellation Cepheus. Its apparent distance is more than 10,000 light years away from Earth. While it fits nicely within the FOV of my 4" scope reduced to 490mm focal length, it is estimated to be about 250 light years across. (For reference, the diametre of our planet Earth is 0.0425 light seconds across!) Multiple stars apparently worked in concert to create the Lion's distinctive shape, with at least two hot, massive, eruptive stars known as Wolf-Rayet identified, as well other bubbles/shells of outwardly exploding gases with stars in the centre discovered. Wolf-Rayet stars are bright, highly evolved, and at least twenty solar masses or greater, which is two followed by thirty zeroes, equivalent to ~334,000 times the size of Earth. It always boggles my mind to contemplate these distances, sizes, and masses, not to mention the cosmic dynamics and dancing that is occurring or has occurred. In addition to its lion shape, there are dark nebulae within the "head" region as well as two large ones around the "tail" (B369|LDN1150/LDN1154) along with interstellar matter Ced203. A small cluster of stars in the "mouth" area, right on the "top jaw" is Berkeley 94, and a dark nebula below the "bottom jaw" is LDN1156. An open galactic cluster in the centre of the "head" is Teutsch 127, residing beside the Wolf-Rayet star WR153/GP Cephei and across from orange hypergiant RW Cephei, in between which there are two dark nebulae, one of which (LDN1161) could be thought of as forming an "ear" and the other (LDN1163) could be thought of as a small "eye" but perhaps the bigger round dark region next to this may be a more suitable candidate. I started on this target last fall and collected ~30 hours of data. I resumed this spring and got it to 60+ hours across all three filters. Everything about this target has been difficult: the capturing was done with and without the moon present causing light gradients, and clouds were a constant presence (I've probably captured another 10 hours worth of very cloudy images). The framing was tricky since I had been capturing it upside down on the other side of the meridian last fall and then right side up this spring and I could never get the rotation angle exactly right between the two sets of frames manually either due to the curvature of the celestial sphere or the change in the position of the mount (which I had taken down for the winter). Fortunately every thing calibrated, registered, and stacked nicely in PixInsight. This is probably the most inconsistent dataset I've thrown at PixInsight which handled it beautifully. However, post processing then turned out to be a chore but fortunately this time the starless technique recommended by Stephen King produced some initial images that gave me hope and encouragement, which led me to learning and applying some of the most advanced processing skills I've ever used on this target. Finally, I was able to get something decent out of it that I now am happy to share with you all. The Lion Nebula (particularly the parts outside the "head") is very faint, which is why I spent so much time on this target, and I was trying hard to get the mesh-like body below the head and outer structures and filaments which shows up the most with the O3 filter on which I collected ~24 hours worth of data. Most of the images shown were processed by first creating an original LHOO/SHO image, removing the stars, light processing, and then putting the stars back at a reduced size. I'm torn between the choices but I've noticed that introducing colour sometimes causes a perceptual loss of detail/contrast (which is why I provide Ha only images for comparison). In this case, it's a very busy field, and the stars cause you to lose sight of how distinctively shaped this nebula is and also the surrounding fainter nebulosity which is most obvious in the starless images. Similarly, since the "head" region in the LHOO is single coloured, the detail continues to shine through. Nonetheless, when you cumulatively examine all the images, you can see how this nebula is deserving of its name! There are aspects (near the feet and even the flow of gases behind the head) that resemble a winged lion from various mythologies. Since I had nice data in each channel, I've posted both the original Ha and O3 master lights (A and B at AstroBin) in monochrome without the star removal or edge tightening processes so you can appreciate the crowded field of stars but also the distinct Lion shape (the S2 is also pretty good). I've also included an original version of a LHOOS image (C; the S2 data is in the luminance channel) with star edges tightened, not removed and replaced, as well as reconstituted versions of both LHOOS and SHO images (D and E) with the same processing otherwise (the colours go from brighter to pastel). Finally, I've included a starless version of the nebula in SHO (F), as well as a fantastic LHOO version by Stephen King (G) which he did early on and kept me going whenever I got frustrated. In my view, C is not bad given its minimalist processing to achieve similar results, but it is not the most pleasing aesthetically. As always, thanks for looking! --Ram

Yes, definitely the amp glow, or an internal light leak. So in the Pacman image I obviously overcorrected but in others I've been able to mask it out or tame it. In my oldest images I struggled with this problem for a while also but I finally got a handle on it enough so that a decent mask plus proper calibration does get it like 90%. The amp glow is actually all along the right, both top and bottom with the middle taking a break. But now I've gotten it so it's only in a small portion of the bottom right corner after calibration. Another issue I struggled with the first year or two... (this is year 3). --Ram

And if you're referring to the right hand corner that is very dark above, that's due to me (poor) masking out the amp glow which is terrible, see the bottom part of this for instance: http://ram.org/images/space/scope/1.4.4.5/veil_sho_20+10x360s_61+20x360s_34+15x360s.jpg ---Ram

Yeah, when I do the starless thing, I put the stars back at a reduced size for this target (which for the smallest stars makes it disappear) but normally I prefer not to do this - each star as you say has its place. As far vignetting, are you referring to the OSC images with the 247C? If so, then I use flats and I have this routine involving flats and flat darks which I subtract to create a master flat dark and it works great for the dust bunnies and such but really seems to be introducing more gradients than not especially once I do the DBE. So I just live with it. Plus I rarely invest time into OSC images - I bought the camera as a way to get to targets like galaxies and reflection nebulae without too much effort and plan to go back someday with a proper RGB setup. With the NB images (163M), it's a hit or miss situation depending on whether I see any dust bunnies but I definitely don't see vignetting in any of them. If there is any darkening towards the corner due to the light drop off due to the cosine gradient, it is again because I've not gotten flats calibration to work properly - I definitely can and do take them with regularity (I keep my camera and scope mounted together for usually a whole season but definitely several weeks at a time) but they don't seem to help with the cosine gradient. --Ram

Thanks! It looks helpful - I have been following the LVA tutorial except for using the PSFImage script to generate the PSF (I did it manually once and this script seems to do better) from Herbert Walker's page (it's a great tool if you've not used it before). And yes, it does exactly as you say - cleans up the data but not sharpen exactly. This is a bit tangential, I've been playing with this great dataset (60+ hours worth) of sh2-132 (Lion) that is frustrating to me and I've thrown everything I can at it but the best SHO image I can generate looks okay but not great but I am able to get HOO images to look near terrific and I know this dataset is great because someone else was able to work magic with it (via HOO again). This is Stephen King's HOO version: http://ram.org/images/space/downloads/sh2-132_sho.v0.1.jpg and this is my solid B quality image (I'm working on the A quality image now) of the SHO/HP: http://ram.org/images/space/downloads/sh2-132_sho.v0.1.jpg There are two major problems: this target has a vast amount of stars in the background and the SHO introduces colours in a way that ruins the detail (I've seen this happen so often - this is why I post Ha images on my AB page for all targets - the monochrome images can perceptually capture detail that colour images seem to mask). If anyone is really interested in playing with the dataset, the XISF files are here: http://ram.org/images/space/downloads/sh2-132_Ha.v1.2.xisf (substitute O3 and S2 for "Ha" and you'll get the other two). The only thing done to it is DC and DBE, no other processing. If you want the files without that, if you substitute "v1" instead of "v1.2" you'll get the original master lights. --Ram PS: Also the starless image looks terrific: http://ram.org/images/space/downloads/sh2-132_sho.v0_starless.jpg - so again I know the data is there - I just want the nebula to show like that but with the starry background. A simple morphological transformation (default erosion) illustrates my point (or if I go to Nebulosity and hit "Sharpen" and to 2.0) and I normally don't like to get rid of all the tiny stars but this case may be an exception.

That's a beautiful starless - I'm surprised you were able to do it "accidentally" - I just learnt to do it and takes me about 10 minutes! --Ram

This is a beautiful image! --Ram

Also includes: Multiple star B 1, Bok globules. Total integration: 16 hours/960 minutes = 54x5m for S2 + 90x5m for Ha + 48x5m for O3. Camera: QHY163M (16mp mono) CMOS cooled to -15 degrees C. Telescope: Takahashi FC100DF Steinheil fluorite doublet apochromat refractor @ f/7.4. Reducer: None. Mount: Paramount MyT. Filters: Astrodon 5nm Ha, 3nm O3, 3nm S2. Software: Sharpcap, PixInsight. More detail and different versions with full resolution are here: https://www.astrobin.com/h9xku6/ - I uploaded reduced sized images to show you the starless version (C) also; the corresonding image with stars is (B) at AstroBin. The Pacman Nebula (IC11/NGC281/Sh2-184) is a bright emission nebula part of Cassiopeia about 9200 light years from us. The nebula derives its name from the video game and in this case, the nebulosity is spans a diametre of 92 light years (so perhaps bigger than its name suggests but very small in the context of the rest of the universe). It contains several dark nebulae within it known as Bok globules, a multiple star in the middle (B 1 or beta 1, which is a quintuple system), as well as the open cluster IC1590. This, like the Wizard Nebula, a popular target for narrowband astrophotographers. The only difference between this image and the last one I did of the Wizard using this almost exact setup (FC100DF at f/7.4) is a Starlight Instruments microfoccuser (MPA-TAK2.5) I installed which let me fine tune the focus which wasn't possible with the factory origin Tak. I had been using the coarse focus which was tolerable at f/4.9 but at its native focal length you can see the difference in the detail and the lack of fuzziness (I'm quite positive my seeing was about the same; average). The double star in the middle of the nebula, and part of the quintuple system, is partly resolvable as two half-spheres. I finally had some success applying a starless technique in PixInsight and I've included versions of the nebula without stars (C) and also an image processed without stars and then the stars added back (B). An additional colour choice is (D) since I find the SCNR palette to be repetitive at times, and as always the Ha only image is (E): https://www.astrobin.com/h9xku6/C/ https://www.astrobin.com/h9xku6/B/ https://www.astrobin.com/h9xku6/D/ https://www.astrobin.com/h9xku6/E/ I think both the main image (A) and the reconstituted starless image (B) look pretty good, with subtle differences that I think will come down to preference. There's some colour noise I was able to tame with TGVDenoise but I've yet to figure out how to sharpen the details while avoiding noise entirely (deconvolution is the next thing I need to learn). Until then, the minimally processed Ha image is where you can see the minute details the most. As always, thanks for looking! --Ram

Thanks x6gas, and no worires. Yeah, it's possible the brightness went down a bit as a result of processing or it got dimmed during the colour combination: if you look at the Ha only image on Astrobin (https://www.astrobin.com/4j0pwf/F/), which is minimally processed, you can see the background is a bit brighter but that's without any Dynamic BackgroundExtraction or Background Neutralization so those processes could've darkened the background. I also imaged moonless (or close to it) on a Bortle 3 sky, so pretty dark (getting worse ever year though). --Ram

There are two things I can recommend, one I learnt early one and one recently. The first is about size. I prefer to size up a large image in PixInsight using drizzle if I am going to print it on a poster or blow it up somewhere. Based on Ken's test, you may not need to do this but it is something to keep in mind for now and future. Drizzle in PI basically sizes up my image to x times as I want it but I have to start early in your processing to get this going. I believe with drizzle I can blow up a image to any size and not lose any resolution (and in fact, gain resolution if I'm undersampled). The second is about the stars. There is a way to minimise artifacts including the ringing and that's something I've just started to do and had some success with. That is by doing most of your processing on a starless version of the image. You can create a starless version in PinInsight (there's a tutorial posted in the forum there) or via the starnet++ program... Hope that helps... but TBH I think your last version looks pretty good as is. --Ram

Also includes: PK107-00.1. Total integration: 27 hours/1620 minutes = 110x5m for S2 + 112x5m for Ha + 102x5m for O3. Camera: QHY163M (16mp mono) CMOS cooled to -15 degrees C. Telescope: Takahashi FC100DF Steinheil fluorite doublet apochromat refractor @ f/7.4. Reducer: None. Mount: Paramount MyT. Filters: Astrodon 5nm Ha, 3nm O3, 3nm S2. Software: Sharpcap, PixInsight. Inline image with reduced quality uploaded to forum. Full sized higher resolution image is here: http://ram.org/images/space/scope/1.7.4.5/ngc7380_110x300+112x300++102x300_1620m_27h.jpg I've been meaning to do this target for a long while but I removed the reducer on my FC100DF so I could get it to fill the frame a bit better (you can see the consequence of not having a flattener with the corner stars and focus is difficult since my FC100DF doesn't have a microfocusser which I've just finally ordered so I can tighten this part up a bit, which should show up in my next image of the NGC281/Pac Man Nebula). This is the first target I've imaged with the FC100DF at its native focal length and it's also the first target I've managed to finish processing since last fall. The Wizard emission nebula is a relatively bright and popular target for astrophotographers. The star forming region was discovered as an open cluster (Cr452/NGC7380) in the constellation Cepheus by Caroline Herschel, whose husband included it in his catalogue. The large active region has a radius of 100 light years and is 7200 light years away from us. The ionised atomic hydrogen from the young stars intermix with space dust in a manner resembling frothy waves and blue flames. The nebula is expected to a last a few million years, though some of the stars will outlive our sun. In addition, there's a smaller nebula (Sh2-143) that is often overlooked when talking about the magical wizard as well as a supernova remnant (PK107-00.1). Given that it had been several months since I had done anything, I was a bit rusty and I had a tough time deciding which version to go with so I decided to showcase a few of them so people can decide for themselves (though my favourite choice is the first one and it has the least amount of processing). Most have to do variations in colours of the "blue flames" and "waves" regions as well as the background but the last one was done by creating a starless version of the nebula coloured using the Photometric Color Calibration process in PixInsight (first time doing both!) and then stars from a simpler version were put back in (thanks to Stephen King et al. for introducing me to the star removal technique). The process worked as far as mixing and matching goes, but starting with the PCC (which may have been a mistake or I didn't do it properly) and working my way to the final image via the starless process caused a some loss of detail that is present when using the more conventional approaches. Still, I've included it here to show what I did using the star removal approach. https://www.astrobin.com/4j0pwf/C/ - different colour choices https://www.astrobin.com/4j0pwf/D/ - different colour choices https://www.astrobin.com/4j0pwf/E/ - different colour choices https://www.astrobin.com/4j0pwf/F/ - Ha only B actually is the same as the main image but without the sharpened stars using Multiscale Linear Transform. What I did was put up the two images next to each other in two browser windows and swapped between them using my keyboard and couldn't decide but there's a difference with benefits and loss of the "natural/pure" look (if there's such a thing, I mean that the main colour image is minimally processed once I got the master lights for each filter, mostly just SCNR and stretching and slight curves aside from the MLT-based sharpening; the others are varying attempts at it). Let me know if you spot the difference and what you is better: http://ram.org/images/space/downloads/ngc7380_sho.v1.61_sharpen_test1.jpg http://ram.org/images/space/downloads/ngc7380_sho.v1.62_sharpen_test2.jpg As always, thanks for looking! --Ram

http://ram.org/images/space/scope/1.4.4.5/ic1396_full_sho_420x40+420x41+420x31_784m.jpg http://ram.org/images/space/scope/1.4.4.5/veil_sho_20+10x360s_61+20x360s_34+15x360s.jpg http://ram.org/images/space/scope/1.4.4.5/ngc7822_153x420+52x360+155x420+52x360+168x420+80x360_4556m_76h.jpg http://ram.org/images/space/scope/1.4+7.4.5+6/ic405_c_shorgb_42x300+24x300+42x300+109x420.jpg http://ram.org/images/space/scope/1.6+7.4.5+6/m33_c_lrgbhos_77x120s+139x60s+10x120s+13x300s+8x300s+8x300s_458m.jpg --Ram