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Found 12 results

  1. Hi guys First things first, apologies for posting this one out of season. A combination of no astro dark, crappy weather, and being busy at work has meant that there's no imaging getting done at all these days. So, i've had to turn to old data to re-process, and this data set was an obvious candidate as i was never happy with how it came out originally. And looking back on it now with fresh eyes, boy did it need it! Nikon D5300, SW 80ED, HEQ5-Pro. 3 x 1200s, 2 x 1380s, and 4 x 1500s of Ha 9 x 1200s of Oiii. 11 x 480s with an IDAS-D1, for RGB stars only 7 Hrs 54 Mins in Total. Stacked in APP and processed in PS. Combined as SHO (using a 70/30 blend of Ha/Oiii for the Sii). The main differences this time were, using Starnet++ to create the starless versions, using more Ha in the synthesized Sii (70% instead of 50% last time), but mostly the improvement has come from toning down the stretch a lot (ok, a heck of a lot!) before making the colour map for the tone-mapping. From then on it was immediately apparent that i'd made a massive boo-boo first time round I've included a 1080p rotated crop too, as i quite liked the framing. Feels like ages since i last did any NB imaging. I almost forgot how much i enjoy it! And rather embarrassingly, here's the original. Try not to laugh too hard!
  2. Having acquired an ASI 1600MM Pro earlier in the year, this is my first attempt at a wide field Ha/OIII bicolour, using a Borg 55FL scope. 15 x 240s Ha and 15 x 240s OIII, integrated and combined in APP and edited in Star Tools. I assigned Ha to the Red Channel and OIII to Blue and Green, but would be grateful for any tips on combining channels for bi-colour images. I also tried combining with the LRGB Tool in Star Tools, assigning Ha to Red and OIII to Green, allowing STar Tools to synthesise the missing data. The result was interesting, but did not produce the 'traditional' Red/Cyan colours of this target. Apologies, maybe someone can advise how I can insert the image into this post, rather than have it as an attachment please? Cheers Dave
  3. As I'm on holiday with relatively dark skies, I've attempted an O3 / Ha bi-colour image of the veil complex, it'll be apparent from the quality that I'm a beginner, especially at post processing. It was done with a mirrorless cam (Fuji X-T1), so needed exposures of 6mins which the star adventurer (or my polar alignment) wasn't really up for, so had to discard a lot of subs, even the ones used show some trailing (8x6mins O3 and 7x6mins Ha, no calibration). Lens was a Canon 200mm F2.8 at F3.4 Used AA6 to stack and do minimal processing, but really don't quite know what I'm doing, still need to watch some of the tutorials. So, just stacked the O3 and Ha frames separately as colour images and then added 0.7xHa to the O3 image. I had fun doing it and probably will try again with my HEQ5 mount back home. Any suggestions welcome, I guess these might be along the lines of don't do narrowband with a colour cam and learn to post-process properly .
  4. Messier 27 - The Dumbbell Nebula M27 is a classic and very popular planetary nebula in the constellation of Vulpecula. Through the eyepiece of a small telescope, M27 takes on the appearance of a ‘dumbbell’ or ‘apple core’ giving it its common name but photographically, the nebula takes on a very different shape, an ellipse at right angles to the more prominent core. A DSLR camera will easily capture this additional detail and deep exposures using a CCD camera will start to show the faint halo surrounding the main nebula. Narrowband images allow a wide range of false colour interpretations to be explored and this is what I am showing here. Discovered in 1764, the true nature of the object was yet to be determined with the misnomer of ‘planetary’ being ascribed to William Herschel in whose telescope the objects appeared similar to planets because of their generally circular shape. This type of nebula lasts for a few tens of thousands of years which makes them a short-lived phenomenon in cosmic terms. Towards the end of a star’s life, the ‘Red Giant’ phase, the star’s outer layers are pushed outwards by powerful stellar winds. Once the majority of the star’s atmosphere has been lost, the hot luminous core emits ultra-violet radiation which ionizes the star’s outer layers previously dispelled, causing them to glow. Rich in Hydrogen Alpha (Ha) and doubly ionised Oxygen (OIII) and to a lesser but sometimes still significant amount, singly ionised Sulphur (SII), singly ionised Nitrogen (NII) and Hydrogen Beta (HB), these nebula respond very well to narrowband filtering. This image was captured in just Ha and OIII with the Ha being mapped to the red channel and the OIII being mapped to both the green and blue channels. Mapped in this manner, red and blue colours similar to those produced by broadband imaging can be achieved but with the additional fine detail and contrast that narrowband imaging can produce. The Ha data was collected during Moonlight conditions and the OIII just after the Moon had set. I need more data to complete this one but I was especially pleased to see the halo in this preliminary version. Image Stats Mount: Mesu 200 Telescope: Sky-Watcher Esprit 150 ED Pro CCD Camera: QSI 683 WSG-8 Sampling: 1.04”/pixel Guiding: OAG/LodeStar Filters: Astrodon 3nm Ha and 3nm OIII Exposure: 23 x 1800 sec Ha, 13 x 1800 sec OIII Date: 24/07/17 - 28/08/17 – much of which was under Lunar illumination Calibration: Bias, Darks & Flats Object Stats RA: 19° 59’ 36.0” Dec: 22° 45’ 57.0” Magnitude: +7.3 Distance: 1360 light years The Individual Ha and OIII Data The Ha/OIII Image
  5. Hello Astro Peeps, I hope everyone is all good! Isn't there some amazing images on this site and others. Amateur imaging has never been so good! I myself have finally managed to get some data for an image, of which I am very happy. It has been so hot here it has been impossible to get any good data. One day a couple of months ago, I hung the thermometer from the grape vine under the back verandah and it was 47.5°C. Sounds far fetched, although true. I live in Adelaide, South Australia and we are 11km from the CBD and usually 1.5 degrees hotter than there! Anyway, I thought I'd try my hand at a Ha, OIII bi-colour image while waiting for my SII data to come in. There seems to be a halo issue with some of the filters for which I will need to do further testing so I apologise for their distracting nature. Details are with the image but basically 3hrsx15min subs for each channel. https://pbase.com/grahammeyer/image/169113477 You can scroll to the bottom to choose another size or auto to fit your screen. Happy photon collecting! ? Details for those that cannot see them. Telescope: William Optics FLT132 Guide Scope: QHY OAG Camera: QHY9 Mono @ -20c Filter Wheel: QHY 7 position Ultra Slim Filters: Baader 36mm unmounted L R G B HA OIII SII Guide Camera: QHY5L-II Mount: AZ-EQ6 Mount Control: EQASCOM Focusing: SharpSky Pro and Sequence Generator Pro 3 (automated) Bahtinov Mask: No (initial focus) Capture Software: Sequence Generator Pro 3 Guiding Software: PHD2 Calibration and Stacking Software: PixInsight Processing Software: PixInsight Number and Type of Data Frames: L= X min, R= x min, G= x min, B= x min Ha= 12x15min, SII= x , OIII= 12x15min. Binning: 1x1 Total Image Time: 6 hrs Location: Lockleys Observatory B, Tanunda, Sth Australia Light Box by Exfso
  6. Hi guys We had a few hours of clear skies here on Saturday night, so I set about getting some O-III for the Western Veil, after I had collected the Ha last month. Thankfully, the moon wasn't around, so even though I didn't get that many subs (only 10) at least they were of good quality. I actually fell asleep during the capture, and woke up to a 'Sequence Aborted' message in SGP and the sight of PHD2 going mad due to thick clouds. Quickly ran outside and thankfully there was no rain about (phew!). I got 11 subs in total, but the last one was totally unusable due to the clouds. The 10th one was affected too, but still looked useable to me, given that I know from experience that APP's 'Quality' stacking mode would know to give it less of a weighting, so I kept it. So this is 15 * 1200s of Ha and 10 * 1200s of OIII (8 Hrs 20 mins in total). Taken with the usual gear: Nikon D5300 (modded); HEQ5-Pro and a SW 80ED. Calibrated with Flats, Bias, and a Bad Pixel Map. APP used for stacking and gradient reduction. Everything else done in PS (including running Carboni's 'Synthesize Green Channel' action). After now having processed both the Eastern & Western Veils, I have to say I have found them to be among the hardest targets to process that I've done so far (although it's still early days for me yet, think I'm still under 15 DSO's and counting). I'm not sure if it's down to the sheer number of stars, or the very faint nebulosity that seems to be everywhere, but I've found the background to be especially difficult on these ones. Getting the Ha and OIII nicely balanced before combining probably has something to do with it. I also tend to do gradient reduction (which seems to affect the OIII a lot more than Ha) on the individual stacks before I combine them, so I wonder if I'd be better just leaving it to later in the process? (which I had to do again anyway, as there was still a noticeable red gradient visible later in the workflow). Something to note, I did go quite heavy on the star reduction. More so than I normally would. I found it wasn't until I upped it significantly, that the nebulosity really started to take centre stage. I like the impact it has made to the image overall, but it made me feel a little dirty at the same time, lol (if that makes any sense). Also, this isn't actually the finished version just yet. I have a bit more work to do on the background and stars (which need their colour toned down in places - probably shouldn't have ran Carboni's 'Increase Star Colour', in hindsight I don't think it needed it). I was literally falling asleep at the monitor last night while attempting to finish it off, and in the end had to admit defeat. So hopefully I can get around to it later tonight. Then the next thing will be the big mosaic of both Eastern & Western Veils. I'm both looking forward to, and dreading it, in equal measures ? As always C&C warmly welcomed!
  7. The Crescent Nebula NGC 6888 The Crescent Nebula rides on the Swan’s neck in Cygnus in a dense swathe of Milky Way stars - an ideal target for my first bi-colour image with my new Astrodon 3nm Ha and OIII filters and Esprit 150 telescope. The nebula was discovered by William Herschel on 15th September, 1792 and he described it as ‘A double star of the 8th magnitude with a faint south preceding milky ray joining to it.8’ long by 1.5’ broad’. This double star is not the prominent star with an apparent companion close to the heart of the nebula, rather, it is ADS13515 at the 2 o’clock position on the nebula’s bright periphery. The bright star off-centre of the nebula is particularly significant as this is the star that is powering the emissions from the surrounding gas cloud. This magnitude +7.5 star, HD192163, is of the Wolf-Rayet type and is also designated WR-136. Charles Wolf and Georges Rayet first described wolf-Rayet stars in 1867 following detection of their broad emission lines. The Wolf-Rayet stage applies to stars with an original mass in excess of 30 times our own Sun’s mass. This stage comes late in the star's evolution when a rapidly expanding shell of hot gas is powered outwards by the stellar wind only to collide with the much slower-moving gas clouds that were ejected thousands of years previously when the star entered its Red Giant phase. These forceful collisions produce a shock wave that generates an enormous amount of energy including wavelengths within the light spectrum, allowing us to observe them. This complex process displays as an arc of bright nebulosity that we identify as the Crescent Nebula. Long exposure images fill in this arc producing a crab-shell shaped nebulous region rich in Hydrogen Alpha and doubly ionised Oxygen emissions. WR-136 is fated to go supernova at some time in the future – watch this space! Image Stats Mount: Mesu 200 Telescope: Sky-Watcher Esprit 150 ED Pro CCD Camera: QSI 683 WSG-8 Sampling: 1.04”/pixel Guiding: OAG/LodeStar Filters: Astrodon 3nm Ha and 3nm OIII Exposure: 30 x 1800 sec Ha, 15 x 1800 sec OIII Date: 11/06/17 + 19/06/17 – much of which was under Lunar illumination Calibration: Bias, Darks & Flats Object Stats RA: 20° 12’ 04.6” Dec: 38° 30’ 46.0” Magnitude: +10.0 Distance: 4700 light years The Crescent Nebula – NGC 6888 Comparison of Ha and OIII data We imagers (well me anyway!) tend to think that Ha is the all-powerful emission line in nebulous objects but it is interesting to compare the Ha and OIII data for this structure as there is an enormous amount of OIII emission present in The Crescent Nebula.
  8. Aenima

    Bi-colour NGC7000 Wall

    From the album: CCD venture

    A h-alpha and OIII shot of the Wall section of NGC7000 aka north america nebula. Processed to resemble the hubble palette colour scheme. ED80 - ATK16HR - Ha clip filter - EQ6 - finderguider 9x50mm PhD2 - photoshop - DSS.
  9. Hi guys After processing the Eastern & Wastern Veils separately a couple of months back, I've finally got round to doing the mosaic that was always the end goal (hence the framing of each panel). I'm not sure why I waited so long to do it, I think deep-down I was secretly dreading it really, as this is my first mosaic so I wasn't really sure how it would go. So this is just 2 panels, and each one has 5 hrs of Ha (15 x 1200s), with 3 hrs 20 mins of Oiii in one (10 x 1200s) and 3 hrs 40 mins of Oiii (11 x 1200s) in the other. So 17 hrs in total. APP was used for stacking, gradient reduction, and the mosaic creation. PS used for everything else. Ha assigned to Red, Oiii to Blue, and Green was synthesized from one of Carboni's actions. I've tried to push it as far as I dare to, did I over-do it do you think? I've resized it down to 66% to help hide some of the noise, and being a mosaic it's still plenty big. I might even end up bringing it down to 50%, we'll see. C&C welcome as always. I tend to finish my images very late at night, so I can sometimes fall into the trap of not seeing the image as clearly as I should! So feel free to be as harsh as you like ?
  10. I have finally managed to collect sufficient OIII data to produce my bi-colour version of 'The Tadpoles', a nebulous region in Auriga. This has not been an easy task as the skies have been most unhelpful and it has taken several nights for each channel often gaining less than 5 subframes at a time! The majority of the Ha was captured under moonlit conditions where the very narrow bandwidth came in very useful. I still have work to do on the stars but will wait now until I have some SII data to complete an HST palette version. Image Stats Mount: Mesu 200 Telescope: Sky-Watcher Esprit 150 Flattener: Sky-Watcher Esprit specific Camera: QSI 683 WSG-8 Filters: Astrodon 3nm Ha and 3nm OIII Subframes: 22 x 1800 sec Ha, 25 x 1800 sec OIII Integration: 23.5 hours Control: CCD Commander Capture: MaxIM DL Calibration and Stacking: PixInsight Post-Processing: PhotoShop PS3 The Tadpoles
  11. Hey guys I shot my 1st full Bi-Colour NB image back in October/November of 2017. It was the Elephant Trunk Nebula, and at the time i remember having a hard time processing it to my own satisfaction. Fast-forward 5 months and, well the weather is bloomin awful, lol, and the nights are now short, so i thought i would re-visit this in the hope i could do better now that i have a bit more PP experience under the belt. The main differences this time (apart from rotating the image to frame it differently) are, RGB combination was done in APP rather than PS. The OIII signal was also given an x2 multiplier to help boost it (this meant i didn't have to give it a big manual stretch in PS). No HLVG has been done at all this time, as i now prefer to leave the Green in, as i think it adds more depth to an image, as long as it's not excessive. This has made a big difference i feel, as from memory i think i really went to town on removing the Green in the original version, and subsequently everything came out brown as a result. I also went with a smaller stretch overall compared to last time, although i did up the Vibrance quite a bit in the new version (i couldn't help myself). Overall though, compared to the original the new version has had a LOT less processing done to it. Whether that shows (or even helps) i'm not completely sure. Still not 100% sure it's the best version of itself it can be, but overall i am much happier with the result. I actually didn't do any sharpening at all in this one, so i could possibly do something there. C&C most welcome please. Have i gone overboard on anything? I had a hard time getting the overall brightness to a level i was happy with. When i thought i had it right, i looked at it the next day at work and on my phone and it looked way too dark, so i ended up cranking it up several notches as a result. 7 x 600s and 14 x 900s of Ha 17 x 900s of OIII (just shy of 9 hrs in total). 50 Bias and 30 Flats Combined as SHO. The SII was synthesized from a blend of 30% Ha and 70% OIII. Taken with the usual gear: Nikon D5300a and SW 80ED scope on a HEQ5 Pro mount. Captured with SGPro, pre-processed with APP and post-processed with PS. Here's a link to the original thread: And the latest version:
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