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4 images in one night from a Quattro

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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.










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3 minutes ago, PhotoGav said:

Wow, good effort. The astro equivalent of speed dating!

Thanks ,yes I like it like that... used to do EAA at video speeds, then progressed to 15s and even 60s subs.  Currently, 1 hour total is more the norm.  May, one day, be up for even longer-term relationships!


1 minute ago, PhotoGav said:

So, who are you going to go on a second date with?!

I have a long list! (But I think I need a 2" CLS filter first.)

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Great night's work.  Look at the dust in the Iris.  That's my favourite although it looks like your flat hasn't quite done it's job.  Plenty to be very happy with.  Good luck with PI, it's like Marmite

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22 hours ago, MartinB said:

Look at the dust in the Iris.  That's my favourite although it looks like your flat hasn't quite done it's job. 

Yes indeed.  I used the wrong calibration set, and also forgot to clip the edges after stacking, which caused all sorts of problems. 

Redid darks and flats today and had another go...


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