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Droogie 2001

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Everything posted by Droogie 2001

  1. Thanks for the confirmation. Shame as the preview window looks better than when applied to the whole image. Still I understand the reasons why. Good to know about deconvolution too.
  2. Wow, another gorgeous image Rodd!
  3. Hmm. May have the answer thanks to Harry Astro Shed. It only works properly on a whole image...not previews Odd that I have not noticed this before! http://www.harrysastroshed.com/pixinsight/pixinsight video html/pixinsighthomenewbie.html
  4. I am getting a very odd and unexpected result when running the HDRMultiScale Transform process in Pixinsight. After starting to rework some of my old data I noticed that after a lot of careful previewing the effects of my HDR process differs on a preview window then it does when run upon the main image. On the below image, the right hand side is a preview window and produces my desired result. However the left hand image is the result (zoomed in) of the same HDR Transform settings upon the whole image, clearly there is a large difference. Nothing has changed with the setting and the mask is the same. I am literally running the same process on the main image. I have ensured that I have not inadvertently somehow running the process twice or duplicating a step. Is this an expected result as it is calculating the entire image as opposed to data on a small Preview window, this does not sound logical at all? Many Thanks
  5. Thanks for the ideas and links. I feel a bit more prepared now, just hope I see the Aurora.
  6. I am going to Iceland for a short break in the next few months so I thought I would have a go at imaging the Aurora. I have an Astro Modified Canon 1100D so my first question is whether I need to switch the White Balance settings to colour correct for daylight photos? This is something I do should I wish take terrestial photos during day time. Normally when taking images of the Milky Way or DSO’s I want to use the enhanced sensitivity to infrared but not sure if this will be desirable for the Aurora? Secondly, I will be using a Samyang 16mm F2 lens so what sort of exposure, ISO and Focal ratio should I be looking at? I am considering 10-15 Secs F4 @ ISO800 as a starting point, the moon will not be a factor. Appreciate some of this will be trial and error but I would like to at least have made some preparations beforehand. Of course, this is all based on whether I am lucky enough to see the Aurora. Thanks.
  7. Stunning image. I can really see a bat or an owl within the nebula!
  8. You don't need darks. You map them from RAW lights. At least I am doing this, though I am trending unfamiliar waters...
  9. You may not want to be using Darks with your Moravian G2-8300 (I have one) as per my current thread, something to consider...
  10. I am currently experimenting on a PixInsight rerun with a BPM rather than dark frames. The BPM list took a while but I think I have 95% of the troublesome blighters. My data set is quite small (3.5 hours) so perhaps not an ideal test but compared to the image I created with the Dark Frames included then there is definitely no increase in noise, whether there is less is hard to say. The main issue I am having is that every time I rework an image I improve upon the previous version which whilst nice is not helpful when trying to make comparisons! I originally assumed that darks were required as that seemed to be preferred method when processing data that wasn't say a Sony CCD chip, useful to know that this is not necessarily the case. At least this may help stop me having to keep building Dark Librarys.
  11. Having had a bad experience earlier this year I had to resort to bin liners! There was a massive 20min down pour from no where which came about after I had set all of my imaging kit up. Luckliy said bin liners did a good one off job and no damage done. I like John's suggestions as this covers the entire mount, tripod and all. I have lots of things velcro'd to my tripod legs so this is an important consideration as well.
  12. Liked the Norton reference that gave me a chuckle! Hmm. Will take a look at BPM's, though I use PI for my calibration etc so will need to figure out where it goes. Sara: Very intertested to hear that you do not use darks with your KAF8300, apologies for the assumption. SGL is great for looking for an answer on one topic only to find that there maybe a half dozen better answers! Thanks all.
  13. Not sure how to subract the average BIAS level from each pixel in the frame? Apologies if I missing something here? I think I will probably run a test stack without darks and see what results I get. I realise I would need to look at Olly's suggestion re defect maps as well. I don't mind creating Dark frames but I definitely want to avoid adding noise. I am using the KAF-8300 chip in my CCD which is prone to noise? I think Sara uses one of these so I know from her images that she has good control over noise levels when Darks are used.
  14. Thanks for the thoughts Olly. - Have you considered not using darks at all? On our Kodak cameras we use a master bias as a dark along with a defect map and a hot pixel filter in the stacking. I find this generally works better than using darks, sometimes much better. I have not really entered the realm of defect maps and hot pixel filtering so I have not looked at this avenue. Its a case of I have heard of it but shied away from it... I will have to carry out some reading and research on the topic. - I'd expect that a small number of darks, of whatever length, would risk doing more harm than good. Totally agree. - Do you need to do 30 minute darks if stacking in PI? I know little about this but won't it optimize a different dark based on the master bias? Not 100% on this. The master BIAS or in my case the Super BIAS I create in PI does not touch on any of the Dark frame creation? Thanks
  15. Certainly makes sense as the greater number of files will help average out the dark noise I guess?
  16. Thanks for the speedy response Sara. Phew that works out at 12.5 hours of Dark exposures. I guess I cant blame the weather when creating these but I am going to need to up my previous estimate. Certainly 25 frames roughly matches up with my current 24 frames for 10mins darks.
  17. Having recently increased my exposure times up to 30 minute subs I am now in need of taking the same length exposures for my Dark frames. I understand the need to take multiple dark frames as part of the calibration process, usually more is better (up to a point). In fact I use a Master Dark when calibrating in PixInsight. That is once I have taken my darks frames I go through the Image Integration steps in creating the master dark file so that I only have to reference this one file from then on. Obviously longer exposures result in having less files when say taking the equivalent total exposure time, for example: 24 x 10min darks = 4 hours or 8 x 30min darks = 4 hours. So I am wondering whether the fact I have less darks frames when taking 30min exposures, do I need to increase this so that the calibration process can benefit from having more frames? Do the algorithms which help average out the dark frame calibration data benefit from more frames, I guess yes is the answer but to what extent? Should I look at taking 8 hours of darks at 30mins so that I can increase the number of frames for calibration to 16 or perhaps even more? Hopefully this makes sense?! Thanks a lot.
  18. Thanks, will keep a note about the cable when I come to switch my filters over in the future, nice Heart Nebula BTW.
  19. Thanks. 3nm can feel like cheating sometimes. Bloated stars are not a problem!
  20. Having never taken an image of the Soul Nebula I thought I would spend some time on this last week. Would like to have added more data but typically the weather is holding this back, maybe in the next few weeks as it’s getting to a nice high elevation now. I see that most people shoot this with the nebula in a horizonal angle but I kind of like this in the vertical as well. Image details: Soul Nebula in Hydrogen Alpha (3nm) Scope: William Optics Star 71 Mount: Celestron AVX Camera: Moravian G2-8300 – Mono Filter: Chroma Ha 3nm 8x1500s exposures (3.5 hours) at -25c Darks, Flats & BIAS Processed in PixInsight Thanks for looking.
  21. Would definitely recommend testing with mains power. Mains power is the recommend method of using the mount but understandably this is not always possible. I have had some crazy slews with my AVX when running on a powertank, 9 out of 10 times it is power. Maybe worth checking this before spending on new parts. Also reset Firmware back to factory defaults. I have had to do this numerous times on my AVX mount.
  22. Nice widefield. I think I can just make out the Veil nebula at the bottom.
  23. Thanks for the advice. Cables are my biggest headache as I have to setup and pack down each time I go out. Will have a look to see if a hub could resolve my annoying issue as well as help speed up my setup /break down time.
  24. Just an update on my previous post. I went out last night with the 5m USB cable and after 30mins and before I had started cooling I had the issue from a while back re-occur. That is SGP freezes and the only way to resolve this is to end task and open SGP again. The main issue though is that after going back into SGP it will not connect to the camera again, despite clicking setup and seeing the camera is there. The only way to resolve is to power off the CCD and power back on after that it connects fine. As mentioned I had not started cooling and it was at ambient. My may concern with this is if I was inside my house and the issue occured potetntially the CCD could be at -25c and then be brought up to ambient very quickly which may or may not do damage to the CCD? It does appears when SGP loses contact that the temperature (understandably) is no longer managed. So it appears 5m USB still seem to be an issue. It could be my USB ports on my laptop or the only other thing I need to check is whether the two 5m USB cables are identical and therefore perhaps a different brand (ideally the same as my 3m one I guess) would help. Will report back if I get any resolution to this.
  25. What amazes me is not just the technical achievement of launching, deploying and landing a rocket but the fact it does it all in about 10 minutes! In that time, it has reached an altitude of 140 Kilometres, a speed of 5500km / hour, it takes me longer to walk to the town at lunchtime! Incredible times we live in.
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