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ChrisLX200

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ChrisLX200 last won the day on November 27 2016

ChrisLX200 had the most liked content!

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About ChrisLX200

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  1. I may be able to help - send me a PM ChrisH
  2. ChrisLX200

    M90

    Excellent M90, and you're right - not often seen ChrisH
  3. Perhaps I read it too simply - but the further away from the Pole you are imaging then the greater the apparent movement will be over time and hence increased potential for drift (tracking error) to show up on your sensor. Also, if your OTA is not orthogonal then this should show up during a modelling run after the meridian flip, pointing errors on one side of the mount will differ (be offset) from the other side and you'll end up with 22 modelling terms instead of 11 (the mount has detected there is a difference between East and West sides of the pier and modelled each separately). I always get 11 terms using the refractor, and usually 22 (not always for some reason!) with the ODK12. I put that down to the ODK12 being less stable and also having larger cone error. I guess I should quote the model data to be sure but I cannot remember the numbers off hand Your final point - yes, re-synching the model simply moves the whole thing using that single offset from the plate solve, if you re-synch (an extreme example) at a point close to the pole where the potential for a solving error (particularly in RA) is greatest then the rest of the points will be offset by the same error - not something you want to do. I suppose if you had to re-synch the model then using somewhere near DEC 0 would be better. Personally, using the refractor, I don't re-synch the model after removing and replacing the OTA on a subsequent night, I just made sure it goes back on the dovetail in exactly the same position. I can't do that with the ODK12 accurately enough (it's just too 'bendy' ) and although I tried I never found re-synching a model was successful in restoring pointing and tracking accuracy with the ODK12, so with that I need to re-run a new model each time I use it. ChrisH PS. My MBox arrived today! Works great
  4. I've always left dual-tracking enabled and not seen a problem, I also always use the maximum number of points available (97+3) well spread across my visible sky to generate the model. I had noticed a couple of years ago when testing various models that an apparent lower RMS may be obtained using fewer sample points but the better performance was to be had with the most complex model - so even though your RMS may be slightly higher using more points the resultant model is probably more realistic. With the refractor I get around 3 arcsec (best 2.5), my ODK12 is usually double that but still usable for unguided imaging. I mentioned my StickStation died a couple weeks ago, it seems (best guess) one or more sensors have failed and it is returning invalid data. Every other function on it works OK - communication with the PC is fine, but when the App (or mountwizzard) tries to evaluate the incoming data it always causes a crash as the data is 'out of range'. So nothing to be done other than replace it and I'm also awaiting delviery of an MBox (don't need the GPS functionality as I already have that). Your M106 result is impressive for a 60min unguided integration but being positioned where it is the mount is not very stressed - choosing a different target lower down along the ecliptic would offer more of a challenge I think. Anotehr good test is allowing a meridian flip without re-centering and checking how close you are to the original target co-ordinates. With the refractor it's bang-on accurate, with the ODK it would be a little out without re-centre. I haven't used my ODK12 for nearly a year but tonight it goes back on the mount - I expect all sorts of new problems to surface ChrisH Edit: Just put the gear away. I had a few problems to start out with - the first model was horrible - 78 arcsec RMS with a dozen failed plate solves. All the big errors were in DEC and I figure the balance wasn't quite right. Ran another model and it was better - RMS of 6 arcsec after removal of one point that was way out. Tracking looked to be good but I was only using 15min subs (2040mm focal length though). I'd forgotten just how heavy that ODK12 + camera etc., is to lift onto the mount
  5. The supprise to me was that, thanks to seeing your image, it might be real data rather than an artifact I needed to get rid of This is not a dark site I image from (the main reason I stick to narrow band normally) so I would not have attempted to target such a faint wide-band feature on purpose. Just goes to show there are still new things to be captured from your average back yard though! ChrisH
  6. It's good to see this! I was struggling with background noise with the Lum channel on the centre part of this area so I reprocessed to enhance the faint stuff. The structures I see are similar to those you show so it must be IFN - real rather than artifacts Doesn't help with the colour channels though - adding those makes a right mess with this degree of stretch. So this is just my Lum channel to show those faint filaments are in the same place (relatively). ChrisH
  7. Dunno about fish - looks a lot more like a pteradactyl than a seagull to me though ChrisH
  8. I like that - almost makes me want a OSC camera because every time I've done a comet with a mono camera it's never turned out well You seem to have a few red spots though! ChrisH
  9. Thanks, and yes - worst season I can remember! ChrisH
  10. Well what a dreadfull season it's been for astrophotography! It's been weeks since I last managed a decent session. This is my first (new) image for ages - a wide-field Seagull Neb in HST palette. 11.5 hrs total integration (started in January!). Full res here should you be inclined to lokk http://s970.photobucket.com/user/ChrisLX200/media/Astro - Images G4-16000/ic2177 HST 005_zpsjgqsqtkf.jpg.html ChrisH
  11. I also get some reflections around the edge but it's not too distracting. This vid is last Friday's RGB disaster, I'm hoping for better tonight - if not I'm giving up on RGB from here! ChrisH
  12. Good result Gina, you obviously have a darker sky than I do - Milky Way very obvious in your capture! I tend to use 8sec exposures with this Fujinon lens and that's good enough to show the quality of the seeing - I'm just processing last Fridays imaging run which was ruined by high Cirrus, the camera showed the potential problem well enough but I stupidly ignored it and went for RGB on M42. Captured data was useless sadly. I'll post the animation when it's uploaded to YouTube. I tend not to use a Dome with this lens as it seems to be sensitive to reflections and distortions, so I just push the camera out the door of the Obs during an imaging run. There's a lot of glass pointing at the sky but it hasn't misted over yet - perhaps because the camera keeps it just warm enough to prevent it (or I've simply been lucky!). ChrisH
  13. You're right Sara, the Ha makes for a poor Lum channel on M42 if used alone - the Running Man certainly is unrecognisable as can be seen in my current effort: http://i970.photobucket.com/albums/ae183/ChrisLX200/Astro - Images G4-16000/HDR ST PI PS_zpsicy3s8t1.jpg~original However, it does appear to add something when layered on top, in desperation I nicked your LRGB data to play with! (I won't post the result though...) ChrisH
  14. Brilliant Sara, could never be bored with an image like that. I'm jealous because you also have exactly what I've been trying to get should this cloud ever go away.. excellent RGB data! ChrisH
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