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Everything posted by markarian

  1. Need some help with this please. Just started narrowband imaging with Baader filters and I'm seeing some very strange effects that I can't explain. Anyone seen this before and how do I get rid of it? Basically it looks like the primary, secondary and spider are showing up on the images. Here is a 200s sub in Ha (2x2) and an associated flat. I get seomthing similar for OIII too - but not SII. Telescope is 250mm f4.8 newt with an MPCC, Atik 460EX and Baader filters. Thanks Mark
  2. Never heard of it? Me neither - but after imaging the Christmas Tree Cluster NGC 2264 in narrowband it will forever be known as the Rat's Head Nebula - to me at least... Can you see it or is it just me? 250mm f4.8 Newtonian Atik 460EX Baader Ha, OIII, SII SHO colour mapping 10x300s each band
  3. markarian

    Ha showing secondary image

    This I took last night shows much better stars without the MPCC than with surprisingly. Even stars in the corners look pretty good.
  4. markarian

    Ha showing secondary image

    Definitely not going to use it - and it seems the 10 inch newt really doesn't need it. As Louise says - the sensor size probably means I gets away with it. In fact the MPCC was doing really weird things to the stars - even at the correct spacing. Not sure what was going on there. It worked fined for the 8 inch newt.
  5. markarian

    Rat's Head Nebula in narrowband

    Ahh didn't know that. Thanks Definitely a rat to me
  6. markarian

    Ha showing secondary image

    Well I've finally decided that it is caused by the MPCC and the Baader filters together - even at the correct spacing there's still some effect. The really weird thing is that my images look far better without the MPCC. I only used it because it was necessary with my 8 inch Newtonian, but this 10 inch seems not to need it at all - and it certainly gets rid of the the horrible reflections / artifacts. Thanks again for everyone's help and suggestions. Mark
  7. markarian

    Ha showing secondary image

    First check is that MPCC distance is wrong. I've adjusted it (not totally correct yet but I'll sort that) and at first glance the pattern has gone! May have been chance that the position I chose just happened to produce a very nicely focused image of the spider and secondary! I'll do more tests to be sure. Mark
  8. markarian

    Ha showing secondary image

    Yes Baader MPCC. Spacers may not be exactly correct - I will need to check that out. Thanks everyone for your help. I have a few things to try out now. Mark
  9. markarian

    Ha showing secondary image

    From the calculator above I suspect I may have 2 possible sources: Coma Corrector and EL lightbox. Can try and eliminate both to prove the point. M
  10. markarian

    Ha showing secondary image

    SX filter wheel. Will check. Are filters not coated both sides?
  11. markarian

    Ha showing secondary image

    They are screw in filters so no other way to go in that I can see.
  12. markarian

    Ha showing secondary image

    Thanks vlaiv - will give those a go. Filters were new Louise. Mark
  13. markarian

    Ha showing secondary image

    One other possibility is the acrylic over the EL panel I use for flats being reflective? Suppose I need to try and change everything to see what works.
  14. markarian

    Ha showing secondary image

    The weird thing is the flats - they show an almost perfect image of the primary, secondary and spider. Final images show it too.
  15. markarian

    Ha showing secondary image

    Flats and subs all show the same in Ha and OIII. SII doesn't show these that I can see. The only thing that's changed is that this is the first real full narrowband image I've done - so a big change really Wondering if it's out of focus reflections from the MPCC to the Baader filters? Mark
  16. markarian

    Ha showing secondary image

    It is an unstacked sub but you can see the same pattern in both the sub and the flat. All subs in Ha and OIII have this. It was reasonably dark last night (or as good as it gets here on the edge of Edinburgh) so don't think it was against light. Both images seriously stretched to show the issue. Thanks
  17. until
    Talk by Dr Paul Dalgarno, MPhys PhD CPhys, Associate Professor of Physics at Heriot Watt University . Black holes remain one of the most fascinating and intriguing phenomenon of the universe. On the one hand they are conceptually amazingly simple, on the other we still know very little about the detailed complexity around them. This talk will discuss the history of our understanding of black holes, some of the main properties of them and touch on some of the deeper questions connected to them. Regular meetings are held monthly and are open to members and non-members. Admission is free and visitors are always welcome. Also at our meetings: What's in the night sky this month News of what's happening in the world of astronomy and space Occasional member presentations Tea/coffee and chat afterwards
  18. until
    Talk by Dr Andrew Dennis, Director of Product Management at Andor Technology. When we think of Astronomy we think of beautiful Astrophotograpy images, but behind the scenes there are usually a vast array of “technical” cameras which ensure the telescope remains aligned, perform deep Astronomical analysis or produce details of the chemical composition of far off worlds. To make a Hollywood analogy, these cameras could be considered to be the Screenplay writers, Producers, Visual effects engineers of the Astronomy world, without these cameras the “lead actors” simply couldn’t perform. Regular meetings are held monthly and are open to members and non-members. Admission is free and visitors are always welcome. Also at our meetings: What's in the night sky this month News of what's happening in the world of astronomy and space Occasional member presentations Tea/coffee and chat afterwards
  19. markarian

    NGC 1514 - The Crystal Ball Nebula

    I found this object the other night, never having heard of it before. It is lovely. Your image is much better than I managed - sky wasn't too transparent and ice forming on everything. Good one! Mark
  20. markarian

    Supernova 2018 ivc in M77

    Imaged this last night - first supernova for me. A little tricky to keep it from being lost in the core but it's definitely there. Mark
  21. markarian

    Supernova in M77 (SN AT2018ivc) Mag 14.5

    I managed to get it tonight with a 10" Newtonian from Edinburgh. Seeing was a bit fuzzy but it's there. Mark (Sorry this is observing - should have been in imaging - feel free to remove.)
  22. until
    For members only We will be discussing field of view, pixel scale, ISO, gain and levels stretching.
  23. until
    Talk by Dr Aleks Scholz, University of St Andrews. The talk will give a brief overview of the star and planet formation process and detail the scientific goals of our citizen science project which monitors nearby young star clusters with amateur telescopes. We will show some of our recent results and explain how to participate in our research.
  24. Juniper Green Village Hall, Edinburgh 7:30pm Members only for these meetings
  25. The annual Doors Open Days at the Royal Observatory Edinburgh will take place on Sat & Sun 29, 30 from 10am to 5pm September this year. Once again Society members will be taking part by bringing telescopes along for members of the public to observe the Sun - if clear! More information from the ROE here: http://www.roe.ac.uk/whatsnew/event/20180929/

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