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geoflewis

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Posts posted by geoflewis


  1. 17 minutes ago, Galaxyfaraway said:

    Very nice image!

    Different star sizes could also be focus? I noticed that with my 8" SCT, I have to readjust focus about half way through the night, otherwise stars beginning to look bigger and bigger...

     

    14 minutes ago, Galaxyfaraway said:

    Could be stacking (do you use DSS?) there is one setting that used to give me doughnut-like stars, I forgot what it was...Could also be partly focus or star alignment (when you add luminance, or if you do different binning). Hopefully someone more experienced will be able to help.

    Thanks yes, all of the above might contribute 😣. Binning 2x2 was the same for all filters as without binning the scope/camera would be over sampled except in excellent seeing, even with the x0.63 telecompressor in train. I autofocus on filter change and monitor HFR as reported by SGP so other than the 4 hours of L shot one night the fairly frequent auto focus routine (~1 hour intervals for RGB) should keep the stars reasonably tight. However, what I do see during poor transparancy is that the Blue filter stars and sometimes the Green stars come out larger FWHM. I don't use DSS, but ImagesPlus and I now use Registar for channel alignment which has significantly improved the channel combination. The C14XLT is old school so suffers from coma, which is just another hurdle in the processing mix to overcome, though the Optec telecompressor lens does a pretty good job with that. I think the main issues are with the processing operator....!! 🙄

    Cheers, Geof


  2. 1 minute ago, Davey-T said:

    Good stuff Geof, you're way ahead of me I haven't even started processing mine :grin:

    Nice PS tutorial here that I use for galaxies but I still get in a muddle hopping back and forth with star masks etc.

    Dave

    https://www.youtube.com/watch?v=2lozs1yu014

     

    Thanks Dave, I'll definitely check out the tutorial later. I'm somewhat a novice using PS, but the software I do use, ImagesPlus (IP), operates in a similar way, so I may be able to apply the methods, or even switch to using more of PS tools. Unfortunately there isn't a very large population of IP users, most of whom seem to be DSLR/OSC camera users, which is how I started out. Hence, finding useful IP tutorials for mono CCD LRGB is something of a challenge, so I'm largely self taught. I keep looking longingly at Pixinsight and APP, but hesitate to jump from one deep dark AP pool to another, as drowning in either will probably kill me.....😧

    Cheers, Geof

    • Like 1

  3. 36 minutes ago, Shibby said:

    Looking like you may have some really nice data but I can't help but notice the galaxy has an unusual appearance, almost as if it's through stained glass window? Perhaps some of the processing steps have been a little too harshly applied?

    Hi Shibby, I think I understand what you are saying, as I too see that 'stained glass window' effect. I've been back and forth with the sharpening of the L data, so I'm wondering whether that has been overdone. As I mentioned above I'm still learning the ropes of LRGB processing, but it's still very much a trial and error (with I fear too much error) process. Maybe I should revisit the data and see if I can improve the image. Thanks for the feedback, Geof


  4. 6 hours ago, astroavani said:

    É um prazer ver que você aproveitou alguma coisa da minha informação amigo Geof!

    Sua imagem também é muito boa e logicamente deve ter sido feita com o C14. Eles são ótimos imageadores planetários.

    Sim, todos os principais detalhes de albedo estão lá na sua imagem, parabéns! 

    Quote Translated: It's a pleasure to see you take advantage of my friend Geof! Its image is also very good and logically must have been made with the C14. They are great planetary imagers. Yes, all the main details of albedo are there in your picture, congratulations!

    Thank you Avani, I always welcome your feedback and encouragement, I learnt a lot from you the past few years 😀. Best regards, Geof

     

    • Thanks 1

  5. 20 minutes ago, simmo39 said:

    Nice, Im with you on the L rgb combination. Cant seem to get the L side to work for me at all.

    Thanks Simmo39,

    I feel as if I'm making progress with LRGB, but I get very inconsistent results. I find that the L can definitely overwhelm the RGB, so I have to back that off in the combination.I also have issues with varying star sizes when seeing and/or transparancy is variable over several nights. Certainly combining the 4 channels has become much easier since I started using Registar to aligning and pad/crop the stacked images, before combining them.

    Whereabouts in Norfolk are you, I'm in south Norfolk?

    Cheers, Geof


  6. Another superb image Avani and the detail on Ganymede is unmistakebly accurate. Thanks for drawing my attention to VPA, which I have just installed onto my laptop. I already had Virtual Moon, but hadn't seen VPA previously.

    I hope that you don't mind me riding your post, but I couldn't resist reprocessing and comparing the VPA graphic with the Ganymede image that I captutred with Jupiter just prior to opposition last year - the one very good capture session that I had all year..!!

    2018-05-06-2350_9-RGB-Stack-Ganymede(resize)_PS.jpg.4419035736f95df8001ecc6fa5e6eb03.jpg975369454_GanymedeVPAcomparison6May2018.jpg.1422483648ae99f32417120a26f12cd7.jpg

    I think that the main features line up pretty well, especially the bright lava flows around the crater Osaris at the bottom of the image. Again many thanks for introducing me to this excellent planetary maps resource.

    Best regards, Geof

    • Like 1

  7. Having seen a few versions of M100 pop up on here the last couple of days, I thought I'd throw mine in the mix. At 11.5 hours it's just a tad more than Olly collected with his dual rig in one night (I wish), but it took me 4 nights of varaible seeing & transparancy. Captured with my QSI583wsg + Astronomic Type 2 LRGB filters through my C14XLT with x0.63 Optec Telecompressor, for an effective ~F7.

    I'm still learing how to combine LRGB, so will be interested in feedback from those that know better than me. There is still some vignetting showing in the right hand corners, so mabe I should crop those out, but anyway here it is....

    M100_LRGB_IP_PS.thumb.jpg.dfb564848463b3906855fb5fa7cb8776.jpg

    Thanks for looking,

    Geof

    • Like 15

  8. I usually split my time between monitoring everything from the warm room in the obs while I catch up on email and web browsing, with retiring indoors to watch TV whilst monitoring the obs laptop via RDC. If it's a really clear night I'll spend some time scanning with my 15x70 binos, or even doing some naked eye obs to see how low magnitude I can see. Often wish I had a 2nd scope to do some visual obs....

    • Like 1

  9. 6 minutes ago, Littleguy80 said:

    Thanks Geof. Was really nice to get out. What are you imaging tonight? Even with visual as my main passion, I still enjoy taking little pics through the eyepiece. The results you guys with amateur kit is astounding to me. Maybe I’ll turn to the dark side of imaging one day ;) 

    That post from Sweden really made me smile. Great to think of inspiring someone so far away. 

    Hi Neil, I'm capturing subs on M100. Ive got an hour each RGB and now into my 2nd hour L - I posted an uncalibrated but stretched single L sub over on the 'so much for the clear night....' thread earlier, if you want to check it out....

    I wouldn't come over to the dark side in a hurry 🤔; I sometimes wish that I hadn't gone down the imaging path as I don't experience the same 'connection' imaging as I do on those occasions when I get into some visual observing. Look at tonight - just a single galaxy target when I could have visited severals 10s at the eyepiece.... I started my particuar AP journey when living in much more light poluted Surrey skies, so not so sure I'd have gone that way if I'd been living in Norfolk from the get go after I retired....!!

    Cheers, Geof

     

    • Like 1

  10. Lovely report Neil and well done getting some more sky time tonight. I'm imaging which as you know is my preference, or is it (?) as I do like some visual connection to the eyepiece from time to time too. I only picked up on your quasar quest today when I saw that post from Sweden and really enjoyed reading the entire thread. Well done getting that one :thumbright:. Cheers, Geof

    • Like 1

  11. Superb images Avani and I am completely envious of the altitude for both Saturn and Jupiter for observers in the southern hemisphere this year. From my location at 52N neither get much above 15° altitude all year - sigh...😞.

    Checking where these 2 planets will be the next couple of years I noticed that the run up to Christams next year (2020) should be spectaclar, with these 2 gas giants passing within approx 1/10th degree (6') of each other on 21 Dec 2020. They will easily fit in the FOV of my C14 with 12mm TV Nagler eyepiece at some x300 magnification for a few days either side of that in the SW around sunset. I'll be sending my request to Santa for an early Christmas present for a run of clear early evening skies and an iPhone eyepiece holder 😁.

    Looking further ahead, by mid Feb 2021 Venus and Mercury both get in on the act in the early morning around sunrise. Mercury will be very difficult, but seeing the other 3 in close proximity for a couple of weeks as Venus first slips by Saturn on 6 Feb, then passes by Jupiter 5 days later should be worth checking out. They will be very close to the SE horizon (>5° alt) in a brightening morning sky, so no chance to get my scope on them, but a few minutes walk along the road from my house I have pretty much 0° horizon to the SE, so I may get lucky with visual / binocular observation.

    Cheers, Geof

    • Like 1

  12. Very sad to have missed this; it was in my diary, but at short notice my wife and I agreed to house sit and take care of 2 of our grandkids down in Surrey last week through yesterday, while our daughter and S-i-L took a trip to New York. Very nice for them and of course lovely for us to spend time with the grandkids and catch up with with other family and friends near our old stomping ground, but the PAS was a casualty for me....

    Sounds like it was a superb event, so hopefully it will run again next year.

    Geof


  13. Thanks again for the suggestions and feedback. Yes, I've wondered about removing the stars to process the nebula and stars separately before recombining them. I've not used stratton (other than a trial some years ago, which I couldn't work out), but my usual AP software ImagesPlus has a star removal tool which I do use for some processing, but I had a lot going on with combining short and long subs with Ha, so didn't try it for this image.

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