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Found 16 results

  1. Hello all! The weekend that just passed we went to my girlfriend's parents. The skies in that rural area are pretty much as good as you can get. I don't have an SQM reader, but Clear Outside estimates 21.91. I didn't take the EQ6R with me, I still consider it a big lump of iron, and the AZ-EQ5 should be on its way back this week as a Stellar mount. So I used the EQ5 which was left in the car for a while. While the tracking/guiding on the RA axis is quite good, the DEC control jumps a lot after multiple consecutive guiding commands, I blame the "enhanced" handset. So with all the drawbacks, I tried to do align the mount as good as I could and I put the 72ED with the ASI1600 on it and a finder-guider. Perhaps also focus could have been done a bit better, FWHM in the subs was 3.x. Below is a quick process from last night, no deconvolution yet and a purple area at the bottom that I have to fix. 58x120s lum, 30x120s each RGB. Last version:
  2. Hi Guys, I thought I would share with you my first DSO taken with my new Orion 8" Ritchey Chretien F8 Telescope. The frame is made up of 12 x 4min shots, no light or dark frames, using my Sony A7Rii camera. The camera had the long exposure noise reduction switched on, which does help to reduce the total number of stars captured by the camera, as the Sony A7Rii does tend to overdo the number of stars captured. The telescope was mounted on my trusty skywatcher NEQ6 mount and the guiding was via PHD 'of course' via my skywatcher ED50 guide scope. The shots were taken from my back garden in Stowmarket, Suffolk where I believe I am a Bortie 4 location, so the skies are mostly dark, with just a little light pollution from the main town, no filters used. My normal telescope is a Skywatcher ED100 Pro Esprit F5.5, which is an incredibly sharp scope, but with a wide 550mm field of view, great for capturing the whole of Andromeda but a struggle with smaller images like the Iris Nebula. I will say the Orion RC scope did need to be collimated out of the box, which was a little disappointing, and it was not just a little out of collimation, it was a long way out, but with the use of a collimating tool, I soon had it dialled in. First impressions of the Orion Ritchey Chretien 8" Telescope are fair, not super impressed, as it is nowhere near as sharp as my ED100 Esprit, but then this is to be expected based on price and telescope type, however, the pictures it has produced are pretty good, if you downscale the full 42MP from the Sony A7Rii camera, as can be seen in this picture. I purchased this 8" Orion Ritchey Chretien OTA mainly for Planetary work, but as yet I have not had a chance to 'get onto' a planet, fingers crossed some clear nights will arrive soon, so I can try. I welcome comments, many thanks Jamie
  3. Hello, The Iris nebula is one of my favorite objects Almost two years ago I managed to get a good image of it during my very first attempts to guide. So decided that it is time to give it a try with my MN190. The night was 16th, the sky was quite good... the humidity was 91%. It is around the normal levels at this location and till that night, it didn't make anything bad to my Tak EM-200. An hour after started the imaging the mount lost connection with the PC and it was the end of the imaging session I was very afraid that the mount is broken but after (as was advised here ) left it drying for a week it is in good shape again and now am thinking how to prevent such problems in future... All that was gathered is only 6x7min at ISO 1600 (modified 550D, MN190 and EM-200, no darks - only dithering). To make the things more fun in 3 of the images there are 2 satellites and one plain... Here is the result: http://www.ideiki.co...es/iris_new.jpg A link to the old attempt: http://www.ideiki.co...ry/ISS_Iris.jpg It was made in 2010 using: Scope: WO ZS 110 + LXD-75, guide ZS 66SD Camera: Unmodified Canon 1000D Exposures: 4h 24min (36x5min + 10 darks frames, 12x7min + 14 dark frames) The advantage of the bigger and faster scope is clear, I wish there were some more data from it... The plan was to gather almost 3h that night... Definitely there will be a new attempt
  4. I've just got back from a mini-break down in Cornwall. The skies were nice and dark, so I took the 'scope with me. To my surprise, I was treated to a couple of clear nights! :-o At SGL9, the plan was to gather some data on the Iris nebula with the goal of collaborating with Rob (Uranium235). Unfortunately, I didn't get the clear sky at SGL but now I have some data to contribute we'll surely have a go at combining the datasets soon... Not sure how well the refractor + reflector subs will combine together, but will be interesting finding out. In the meantime, here's the stack of my side of the data. Quite happy to capture some of the fainter dust (albeit a bit noisy still). I feel this would have been impossible to extract from my light-polluted skies at home! 38x600s + flats, ISO800, Canon 450D Skywatcher 150PDS Vixen GP + finderguider & SPC900
  5. So after Carole helped me to realise that I was taking my flats wrong, I've reprocessed this image and finally the funny rings have vanished. Original thread TL;DR - I was underexposing my flats, which resulted in failure of calibration to remove vignetting, as well as it introducing weird red concentric oval rings. Last night was supposed to be clear, so I set up in the garden. Cue the Irish weather. I only managed to get PA and focus (you know, the most fun bits) and then the clouds rolled in. Anyway, so instead of imaging, I took a bunch of calibration frames. The setup was slightly different to the lights - 1) temp 4 C instead of -1.5 C (no big deal) 2) camera at different angle to telescope (can't correct dust motes) 3) new camera angle adjuster in path (different vignetting and internal reflections) so I didn't hold out much hope that it would correct the problem. But it did! I used the new bias and darks to correct the new flats, and then the old bias and old darks and new flats to correct the lights. I'm so pleased I've finally figured out what was going on as it's ruined many images for me over the past year+. Thanks again Carole, Barry
  6. From the album: Deep Sky

  7. Here's a little run at the Iris Nebula in Hydrogen Alpha... Now it isn't much to look at, but it's all i've managed so far. 127mm triplet, Atik 428Ex and a AZEQ6 1h15m total exposure. 5 x 15min in Ha This thing is really difficult in Ha... i'll have to go deeper next time.
  8. I wondered if I could do a little better with the data that we got from our trip to Les Granges in November. Our last effort got to this: https://stargazerslounge.com/topic/280758-ngc-7023-iris-nebula-from-les-granges/?do=findComment&comment=3075021 I went back to the un-stretched data and reworked it. The aim was to try to bring out more of the faint stuff without blowing out the stars. This version seems to have a bit more sparkle and so I hope you will forgive me for reposting it. As before it is: 18 x 900s each of RGB 21 x 1900s of Lum Shot through Olly's Tec 140
  9. Hi Guys/Girls I had a chance to get out in the garden last evening, had a go at capturing NGC 7023 - Iris Nebula, only managed to get 12 good shots, 240sec x 12, combined in Photoshop with Mean Stacking. The dew was super heavy and currently I do not have any dew heaters (next purchase) so lost the battle after around 2 hours. One interesting point is I captured these shots with the long exposure noise reduction switched on with the Sony A7Rii, so each shot took 8 mins to take and save, but as a result the noise levels were next to zero at 800 ISO, and at the end of the day the noise is always our enemy. I need to try a real pro level 'cooled' astro camera just to see how much better it could be, as the Sony A7Rii is just stellar ! I am very happy with the final shot, taken with my Skywatcher 100 ED Pro Esprit Scope on my NEQ6 mount, Skywatcher ED50 Guide Scope and Altair Astro ASI130mm camera, PHD2 of course. The sky was nice and clear with low light pollution, as around 5 miles from major town. I do not take darks or flats or use Deep Sky Stacker, and I do not use filters, plus the camera has not been modified, so I am always delighted with the results I get from my set-up, as I have a deep level of respect for the hard work that most Astrophotographers go through to get the incredible images that we see here in Stargazers. I have read that some people believe that the Sony Alpha cameras have a tendency to 'eat the stars' and not show everything captured, to be honest, I always used a Canon 60Da for many years for my astrophotography, until one day I though, what if my Sony A7Rii could be used, the first time I did this I released that it was time to sell the Canon 60Da, the 'Remote' (free) Sony software is almost as good as BackYardEOS, but the cameras are a decade apart in performance, the noise levels on the Sony are at least 4 maybe even 5 stops better than the Canon, that is the Sony A7Rii at 3200 iso equal to the Canon 60Da at 200 iso, so at 800 iso it is just so impressive. As you can see from the picture only 12 frames, stacked in Photoshop (Mean). Open to comments and welcome a discussion/debate, thanks Jamie
  10. Well it was a good night, weather-wise, last night (12-Nov-2017) in this part of Oxfordshire. Cool (3 degrees) but amazingly dry, really (85%.) And so, for once, everything wasn't covered in dew by the end of the night. After an earlier debacle with coma-corrector spacing, I've shaved off a further 0.5mm to try and tweak it a bit better, but I've also (for my sins) started a trial period with PI. I've so far eschewed this box of tools in favour of simpler, and some home-grown, things. But I'm interested in finding out more about what so many people use... even if only to understand the PI-speak language a bit better. As a result of all this, I want to try things out on some smallish datasets, and ended up with: Crescent, 12 x 300s (60 min) Pelican, 17 x 300s (85 min) Iris, 12 x 300s (60 min) Horsehead, 6 x 300s (30 min) Quattro 8" on Avalon M-Uno, QHY8L OSC, captured, guided, and dithered, by Nebulosity, pretty poorly processed in PI (my fault, not its) including bias, darks, and flats. Some observations about the images: Crescent... a difficult RGB target, I've tried but failed to reduce the background stars Pelican... just a bit too big for the frame, but the extra data (more than 60 mins) helps with noise Iris... real problems with the background. The APS-C sensor is just a bit too big for this scope? Horsehead... my first ever attempt at this. Pleased to have resolved the Alnitak double. Sad to have framed it so poorly for the Flame. No doubt the processing is very ham-fisted for my first use of PI, so any C&C is positively encouraged! Thanks for looking.
  11. Hi guys, this is my effort on the Iris Nebula with a Tak FS-128 from a dark sky site in Ireland. I was being greedy, doing multiple targets on the same night (March 17th) so I only captured 2 hours on this one. Takahashi FS-128 with 0.75X reducer/flattener on Vixen AXD2 mount 60 X 120s with Nikon D750 Processing in PixInsight and Photoshop There's something funny going on with the rings in the background, which I have not been able to get rid of. This was from a truly dark site (Bortle 2) and the subs don't show any sign of these rigns, just the usual vignetting. I think the calibration is actually introducing the effect. I took flats and all that jazz, and did all the calibration in PI so I don't know what I'm doing wrong. Has anyone seen this kind of thing before? Comments and suggestions welcome! Barry
  12. Whilst California was being collected - https://stargazerslounge.com/topic/280659-355-hrs-in-california/ - we pointed Olly's TEC 140 in the vague direction of the Iris Nebula. Over the course of 3 nights, we got hold of 4.5 hours each of RGB for a total of 13.5 hours, plus 5 hours and 15 minutes of Lum. We extracted a synthetic luminance from the RGB and added this to the 'real' Lum (estimating that it gave us an equivalent of about 3 hours Lum). I was at the keyboard but Olly was hovering over my right shoulder prodding me in the right direction. We managed to get the praying ghosts in frame, which was a bonus.
  13. My setup: Telescope: Skywatcher ED80 Camera: Modified 700D Guiding: QHY5L-ii m + finderscope Image Capture: Astrophotography tool Processing: DSS + PS or Pixinsight Filters: Astronomik CLS clip on Over the last week I managed to get two nights with the telescope, both of which were spent capturing the iris nebula. On the first night I got about 1.5 hours and on the second night I managed a whopping 7.5 hours. I give thanks to the recently purchased 700d AC power adapter for that long stint. I live in a relatively light polluted area, but I can still manage to see the milky way on a clear night. Now, I usually image relatively easy images ... orions nebula, horsehead nebula, rosette, heart and soul, using the above setup as well as with the canon 200mm lens. The iris nebula on the other hand I wouldn't consider as easy a subject as the rest, given my FOV and the fact that most of the interesting artefacts around the nebula consist of VERY FAINT dust lanes. In any case, I decided I wanted to take the leap and just go for it. A concern of mine was the colour of the stars; I wanted to make sure that I didn't clip any of them, and so I decided to expose my subs to accommodate this, which lead me to 240s subframes at ISO1600, dithered. This is what the histogram looked like for one sub: And this is what a single sub looked like without any processing/calibration: The stars seemed sharp enough and I had both the Iris in view as well as the ghost nebula (just about) keeping it company. My train of thought has always been that even if a single sub doesn't show the detail I'm after, stack enough of them and it'll soon appear. I went ahead and captured the images, got the corresponding flats, darks and bias frames and then ultimately started to process the images. This is what the histogram looks like in PI before and after I apply the DEFAULT screentransferfunction curve: And this is what the image looks like, without any post-processing other than Automatic Background Extraction and a 180 deg fast rotation: There are a number of things that concern me about this image. The colour motle/noise what ever you want to call it. There are blotches everywhere. The level of luminance noise which for 8+hours worth is simply disappointing. The lack of detail in the dust lanes. I come back to the title of this thread: Where did I go wrong? I apologise for the length of this post, I was just trying to be thorough.
  14. Here's my latest, taken over a couple of nights this summer: 17x600s L 1x1, 17x180s R,G and B 2x2 binned (don't like the 2x2 binning, no binning for me from now on). Flats, darks and bias, equipment as per sig, Pixinsight. The Iris Nebula (NGC7023) in Cepheus is a dark nebula and reflection nebula. The dark cloud of inert dust and gas obscuring the background stars is illuminated in the centre by a mag-7 star, reflecting pale blue starlight. It is 1,300 light-years away and 6 light-years across. Hope you enjoy !
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