#21  
Old 06-10-2013, 10:12 AM
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madbadgalaxyman (Robert)
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Originally Posted by Suzy View Post
Robert you're amazing, thank you so much for all that fabulous information.
G'day Suzy,

I think that the "square" look of the bulge of NGC 6771 could be difficult to see visually, even in a dark sky, if these near infrared isophotes of this galaxy are anything to go by:

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In general, because isophotes are lines of equal surface brightness, the outlines of the inner isophotes of a galaxy are all that the visual observer tends to see, unless conditions are absolutely superb. So this galaxy will probably look boxy only if the observer can see to faint levels...... which is tough unless you have CCDs in the back of the eyes.

A better match for visual observations is the near infrared JHK (or J+H+K) images of galaxies from the 2MASS survey. While these are infrared images, they are very short exposures of modest angular resolution, so they are closer to what an observer might view in perfect dark sky conditions.
Here is the 2MASS image of NGC 6771:

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By the way, thanks for the positive review of my posts; most flattering.

I also do find your posts to be interesting; because I have gradually moved progressively ever further away from having the perspective of a dedicated and enthusiastic visual observer ("kicking the 4 inch Apo onto the verandah from time to time, does not a serious visual observer make" - R.L. ). You are good at describing what you see at the eyepiece, and this makes for interesting reading.

I don't do much serious "looking" these days, instead navigating "data space" and the scientific literature and the vast databases of galaxy images. There are billions of unanalyzed observations out there, so I find it a more efficient use of my time to use "other peoples data". In any case, the Visual Galaxy Observation that was my bread and butter till the late 1990s required extremely dark and transparent skies; which meant long commutes with lots of heavy equipment to dark sky sites.....very time consuming.

Best regards,
Robert Lang
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  #22  
Old 28-08-2023, 07:40 PM
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Zubenel (Wes)
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+10 years since the last post. IT LIVES !! I highly respect this discussion .One that google picked up very early .+ After viewing the brightest members of this Super cluster including IC4765and a poor go at imaging it through Zamar 2 years ago , we recently have returned from Blackall QLD where 5 hours of exposure through my recently acquired Skyrover 102mm pro Apo has given pleasing results.
https://astrob.in/eyg1yb/0/ There are no less than 261 galaxies captured. Mega Awe and wonder Folks.!!!

Last edited by Zubenel; 28-08-2023 at 08:54 PM. Reason: spelling
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  #23  
Old 28-08-2023, 09:26 PM
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Tinderboxsky (Steve)
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Fabulous result, Wes.
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  #24  
Old 28-08-2023, 09:33 PM
Dave882 (David)
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That a fantastic Wes - I've recently been adding some data to a longer fl version of the central cluster. It's just an amazing area to explore!!
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Old 11-09-2023, 09:24 PM
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Fabulous result, Wes.

Thanks Steve
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  #26  
Old 11-09-2023, 09:26 PM
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That a fantastic Wes - I've recently been adding some data to a longer fl version of the central cluster. It's just an amazing area to explore!!

Thanks David.I am sure I speak for the masses ,I will look forward to your image outcome ! I hope it betters mine. Please post here to continue the tread.

Last edited by Zubenel; 11-09-2023 at 09:27 PM. Reason: spellimg
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  #27  
Old 11-09-2023, 09:41 PM
Dave882 (David)
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Thanks David.I am sure I speak for the masses ,I will look forward to your image outcome ! I hope it betters mine. Please post here to continue the tread.
Here’s my offering at 2670mm with the ol’ c14. It’s all B7 data so not going to find any IFN there unfortunately but some interesting detail and even colour on display in some of the galaxies.

...and the thread with some more details
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