Celestial hemisphere:  Northern  ·  Constellation: Ursa Major (UMa)  ·  Contains:  NGC 3718  ·  NGC 3729
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NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann

NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14

Getting plate-solving status, please wait...
NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann

NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14

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Description

These are 2 images in one ... almost that is. I would have liked to have more comparison images between the 2 different setups, but decided very quickly that it was not worth continuing with the 2x - f/14 images, since they were ... well ... see Version E for yourself. I used the same exposure times, and fairly enough same weather conditions, and as expected, there is much less to see at f/14. I definitely hoped for more details, 1850mm focal length, but if there is not enough signal, then one cannot see more details. I spent on the 2x Barlow setup 16.5 hours, yes, less than for 1x, but I saw already when processing the 2x data that I will not be able to get a decent image out of it. This was also the first time that I tried bin 1x1 for the 2x setup, this really did not give more, I actually like the images from last year with bin 2x2 better! So this was it, the second (M44 was the first one) and the last image this year with the 2x. But I will still use it for planetary targets that I will start at one point of time. 

The processing of the 1x1 took an eternity, since I wanted to see if I could get a result under my skies that I could "live" with. Well, that was a close call, these were not just a few hours, these were combined days of processing work, just could (and still can) not get the image look the way I had in my mind, very humbling! At least I learned a bunch of new stuff, using GHS for the very first time in a final image, now that is really new. So far the results using GHS were mediocre, to say the least, for some reason though it looks like that galaxy images are better suited, especially the background noise was by far better than the standard Histogram stretch. Ahmed passed me also a video about getting color into the image, and yeah, that helped as well quite a bit, never saw this process before. There is a ton more that I used to get this image, cannot even remember all of it. Did I use now all possible methods that PI offers with this one 😊? No, not by far, but I am coming closer 😊. 

With this being said, any LRGB images from my backyard will probably require the same amount of work (and integration time!!), and I am not sure if I want to go through this again. Hence maybe that was also the last one that targets galaxies, sorry Andreas 😊!
* This image was not submitted for IOTD consideration

Comments

Revisions

  • NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
    Original
  • NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
    C
  • NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
    D
  • NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
    E
  • NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann
    F

C

Title: Annotated image

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D

Title: less stars

Description: There was recently a debate about "missing" stars in many new images (Carastro I believe started it), very interesting topic and good replies (except one person of course ...). I believe this comes up now more and more often since the usage of STX makes it possible to stretch the starless image different than the star image, and who likes bloated stars? Easy solution: stretch minimal, resulting in way less stars. This is how it would look like compared to the final version, for which I added as many stars as I could. They do belong in our images, we are taking images of the night sky! I am actually always fascinated when I see them, so so many, wonderful!

Uploaded: ...

E

Title: The f/14 comparison

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F

Title: 3 years later ...

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NGC 3718 and NGC 3729 in LRGB, 1x - f/7 and one comparison image with 2x - f/14, Uwe Deutermann