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AKB

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  1. Yes, I had that too… the trouble is that it’s all overseen by a Mk 0 brain!
  2. AKB

    Arps a-plenty

    Good thought, but apparently not. I was wondering, perhaps, whether it's the debayering, which spreads a hot pixel into multiple ones and may cause detection to fail.
  3. AKB

    Arps a-plenty

    Thanks for that. Interesting, I’ve never used my 294MM in that mode (which would also receive four times fewer photons), but always binned x2. Everything's a trade off! Tony
  4. AKB

    Arps a-plenty

    Well, technically at least, there should be two advantages of mono: captures more photons, since the Bayer matrix of a colour camera limits any one pixel to R, G, or B. better resolution, since the synthetic L from a colour camera is made up of three or more pixels. In practice, however, that's exactly the question to try and answer. It appears that modern debayering algorithms are quite good at preserving resolution. Almost an inevitability with a RASA, since whilst I love EEVA, it's main use is likely 'proper' imaging, and you're not going to be swapping cameras all the time between mono and colour, or swapping filters, really.
  5. Ooh, that's really nice – you certainly do have a 'decent image'. I just tweaked it a bit more, with some noise reduction and a few other things in PixInsight... not sure if you can do this in Siril ?? Hope you don't mind me posting this... Tony
  6. NOW you tell me … ! See my post of last night’s session:
  7. The chance to actually observe something last night was so exciting that I nearly scuppered the whole thing by starting to move the mount (remotely) before opening the observatory roof! Cut the power to the mount just in time and went to see the damage. Fortunately, just the flexible dew shield had crumpled against the observatory roof and stopped short of the camera sticking out of the corrector plate. A close thing, and not a great start, but it got better... I'm trying to quantify the the tradeoff between my previous Hyperstar/mono camera combination and the current RASA/colour OSC one, so I'm targeting some of my favourite, er, targets - Arps - starting with big and easy, and then getting smaller and tougher. So last night, I managed the following, all 1 minute subs and generally 10 of them. Due to Jocular's feature of splitting OSC images into separate mono ones, a ten minute grab shows as a 30 minute one in the annotations. Arp 337, aka M82. Also M81 through an almost complete accident... I had chosen the wrong ROI for the camera (ASI294-MC) normally using about a quarter of the available field, but this time it turned out to be a 2:1 aspect ratio – perfect for this combination! Arp 85, aka M51. Arp 26, aka M101. Not much colour on show here. Arp 214, with an inverted mono image to examine the structure more closely Arp 317, the Leo Triplet, looks very soft... I refocsed after this. Arp 320, Copeland's Septet, also a Hickson grouping M109, this isn't an Arp, but it was nearby, so didn't want to miss it, and all its friends which are labelled in the eyepiece view. Arp 104, Keenan's system. The key here is to observe the bridge between the two galaxies, an inverted image helps. It's going to take some time and effort for me to assess the differences between these and my previous versions, but qualitatively I would say: The OSC isn't a significant handicap, compared to a mono, but... ...still mulling the benefits of colour. I'm struggling a bit to get a good colour balance with Jocular There are no calibration frames here at all. I definitely need to get the bad pixel map working for colour (any pointers @Martin Meredith ? I know that OSC is not top of your list!) It was a complete blast to have a romp around Ursa Major and Leo on a relatively clear (although not ideal) night. Hope there's something of interest here for you too. Tony
  8. Skipper, I'm sure you've thought all this through, so I'm interested in your chosen option for the orientation of the roof, and its direction of travel. I assume you're keeping the apex design, and your chosen direction of travel is towards your less interesting horizon... perhaps north? It looks like your floorplan is square, so whatever the direction, you still have a choice of the orientation of the roof ridge – is that going to be parallel or perpendicular to the direction of travel? If parallel, then when open, you get left with the gable end on the far wall, which may obscure some of your horizon. This seems to be the usual way of doing it, for some reason. If, however the motion is perpendicular to the ridgeline, then you'd have the lower edge of the open roof against the far wall and the highest point of the ridge further away, so a lower useable horizon. Perhaps it doesn't make enough difference to care about this, or perhaps there are other engineering constraints? Just wondering. Whatever, good luck with the process! Tony
  9. Turns out that this is easily added in Stellarium using the Solar System editor and importing it from the MPCAT list of numbered objects.
  10. Aha! “Mars Attacks”, I believe…
  11. Well, seeing that you have Feb 10 and Feb 12, here's Feb 11... ...a 5 minute stack of 30s subs using Jocular (ignore the 15min label, it's because Jocular splits and OSC RGB into separate subs.) Tony.
  12. ...and in a slightly yellower treatment, it could surely be Homer Simpson??
  13. With any filer, may I ask? UV/IR perchance? Tony
  14. Really glad to hear you’re getting up to speed with the Hyperstar. Enjoy! Tony
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