Some photos

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Xelasnave.1947, Sep 23, 2019.

  1. Xelasnave.1947 Valued Senior Member

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    Thank you.
    Digital is the reason I expect.
    I suspect that I would firstly get more practice as back then a professional probably only did one long exposure each evening whereas say taking last night as an example probably took around 300 photos many of which I threw out because they were not "perfect".

    They would not have been able to stack and had to push film hard for a result.

    Astro photography is now in the hands of ordinary folk and with dedication to detail it is relatively easy to produce acceptable results.

    I captured data last night with my Nikon D5500 and my 80mm two Astro graph and will be processing for days I expect.

    It was great having two rigs going.

    I am working on "The Chimney" (a neat dust lane in the Milky Way) right now and can't wait to see how it turns out..Taken with the Nikon D5500 I did something very unusual by setting the ISO at 22500 .. You just don't do that usually ISO is either 800 or 1600 ...1600 being considered "extreme"...It is coming out of the stacking process now, very slowly because I was able to drizzle at 3x, but looks ok but the file may be so large that my lappy may crash when I take it to StarTools.
    It has taken 30 minutes and hopefully another ten the stack should be complete.

    I think this will be a first ...like if you know what you are doing you just do not go that high with your ISO...But the histogram looks excellent.
    Alex
     
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  3. Xelasnave.1947 Valued Senior Member

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    Well the file came out at 2.42 gig and the software didn't want to know so I am trying a stack at 2x drizzle which will result in a smaller file and hopefully I can process it... If that does not work I will stack it again with no drizzle. Because of high ISO I only took 43 frames each of one minute ...it's staking fast now...only 40 minutes to go plus time to load final.
    Alex
     
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  5. elte Valued Senior Member

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    You're welcome.

    I await the result of the experiment with the high ISO setting.
     
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  7. Xelasnave.1947 Valued Senior Member

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    43 light frames 30 seconds each and 20 dark frames. 12o fl but heavily cropped. Stacked Deep Sky Stacker, Star Tools, Photo Shop and Gimp.
    I rushed it a bit but very happy for first try at this approach.
    After stacking the file size was 1.2 gig, Image binned at 25%....

    This suggests to me that one could use a static tripod and shorter exposure times but more of them to get a similar result … I should try that to encourage others to have a go.

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    Last edited: Apr 25, 2020
  8. Xelasnave.1947 Valued Senior Member

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    ISO was in fact 25600.

    alex
     
  9. elte Valued Senior Member

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    The result has pleasantly surprised me.
     
  10. Xelasnave.1947 Valued Senior Member

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    I tried to get rid of the green.
    I think I like this one ... I have been processing all day I have lost my objectivity. Please tell me which one is preferred.

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    Alex
     
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  11. Seattle Valued Senior Member

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    Yes, the last one is the best. Very nice!
     
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  12. Xelasnave.1947 Valued Senior Member

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    Here is another I just now finished, Iwanted to see if the Cats Paw Nebula would show up..it did but I doubt if it will jump out at you..its only about a quarter inch...anyways high ISO again..25600 but no darks and the noise is not too bad..I do not know what is happening to the colour...but I went with it..its just wrong I thought.

    alex

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  13. elte Valued Senior Member

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    When you mentioned uncertainty about the color, I turned off the blue filter on my display screen to look at those three images of the Milky Way. I can just think to say that each of them is cool to view. I recall captions on various photos that have been taken from Hubble over the years, often with mention of intentional color adjustments or enhancements.
     
  14. Xelasnave.1947 Valued Senior Member

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    My problem is I am marginally colour blind which manifests in displaying say purple when blue is required, and green and brown are difficult to separate.

    However maybe it is a blessing in that I am more focused in detail ...so if the detail pops out by turning the dials too far to red and I get purple but better detail I don't worry.

    I do, once I get the detail, try and return to "normal colour", by seeking a second opinion.."There seems to be a lot of green" or " that blue is purple at one end"...and when I move to top gear I use an app on my phone to tell me each colour...you take a photo of a specific colour and the app tells you exactly which colour. I can convert my detailed image to black and white to preserve detail and then merge it with one having perfect colour.

    And as you observe Hubble perhaps takes liberties with colour.

    Generally we use a "Hubble Palette" when say Hydrogen alpha is mapped to red or brown...O11 mapped to Blue ..I think it goes that way but the point is channels other than red, blue and green seem to be set by a committee...I like to think I can colour things whichever way I decide.

    Other astrophotograpers say I am artistic which is their way of saying the colour is unconventional.

    I had another great night last night..I have maybe eight hours of good data on the Running Chicken Nebula in all channels..RBG Luminance, Ha (particulary very good), O11 and S11 and managed 500 frames, on my Nikon only set up, of high ISO stuff to play with... I am experimenting to see how far I can drop exposure times and still grab reasonable detail.

    I need to buy another cooled astronomy dedicated camera and probably will get a one shot colour to minimise the work load ... although I guess what I need in another cooled mono with seven filters and a second processing computer...I really can see two scopes each with a cooled mono camera, each scope with its own lap top for guiding and image acquisition and two desk tops to procees data each one dedicated to data from one scope...It is getting outta hand but I do like doing it so even if 16 hours of my day go to capturing or processing I am happy..what I do need is a cook...When I am here I am resting...mmmm maybe move the bed into the kitcken area like I had set up on my boat...
    Alex
     
    Last edited: Apr 26, 2020
  15. elte Valued Senior Member

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    My brother is color blind.. Having two telescopes reminds me of radio telescopes that are located far apart and whose images are combined having a bigger virtual aperture.. I can relate to basically living in the kitchen because of lacking resources, including like in your case, time and convenience. I also have a bit of lack of mobility but not so bad as yours. Hopefully your foot gets better. I can relate to some foot trouble.
     
  16. Xelasnave.1947 Valued Senior Member

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    I conceptualised the "Dragon Fly Array" years before it appeared and so was happy that my wild idea worked...I have software that shoud enable me to combine the data from the different units..it's called Registar and if it works the way I think it will, having two scopes and combining their images should be a big step forward..if nothing else it doubles my time...I posted some earlier results earlier in this thread somewhere.

    The problem was in my back, a vein and artery merged requiring delicate surgery around my back bone, I was very lucky not to go paraplegic but my legs are "on fire" from the knees down...one has to grit ones teeth and not sook but it means I spend a lot of time on my back...still even today I cut up a few branches from one the fallen trees...one down and one hundred to go...but I now need to rest..however the lappy is running hot with a process happening, stacking 155 light frames with no darks to see if the large number manages the noise from a high ISO...so I feel busy.
    But the big problem is my lack of stability cause I don't feel the ground under my feet and having a tumble with a chain saw running scares me somewhat.

    This stack and process will be interesting as it was at 200mm fl and the subject is a globular cluster (requiring perfect focus which is near impossible with the 200 dolllar Nikon lens) and a gallaxy each at edge of frame ... doesnt sound much but I will be happy if I can bring out the detail required of the globular cluster on one side and the dimness of the faint gallaxy on the other...as I said it's really pushing a 200 dollar lens. Because of the large number of frames I can not drizzle which would have been a big help on this project...

    Alex
     
    Last edited: Apr 26, 2020
  17. Xelasnave.1947 Valued Senior Member

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  18. Write4U Valued Senior Member

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    Never seen anything like it. Truly astounding.

    Yet I like the more selective pictures with greater detail, they seem to have personality (patterns).

    p.s. something struck me as being a possible functional cheap retractable roof. Use the retractable roof of an old convertible car! Manual or electric, seems like a perfect way of quick and reliable way to open the roof for sky-gazing. Doable?.......

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    Last edited: Apr 26, 2020
  19. Xelasnave.1947 Valued Senior Member

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    It could be made work but probably not sufficient area.
    My roll off roof is as simple as a brick and although I had planned to motorise it I don't think I will bother...just another item to power and maintain.
    Your idea would be ok for a small set up.
    Alex
     
  20. elte Valued Senior Member

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    That was good how you had conceived of dragonfly.. Hoping your surgery heals up.. I look forward to finding out how it turns out with the globular cluster and two adjacent galaxies image.
     
  21. Xelasnave.1947 Valued Senior Member

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    There is only one galaxy Centurus A (on the left) and the globular cluster Omega Centuri on the right..the stacking is complete but I am stacking more stuff so I can't process anything...both the stacking program and the processing program won't alĺow a tithing whilst either is running.
    However the stacked image seems ok but I really won't know until I run it thru Star Tools and Photo Shop.
    What I might do is use fewer frames and run a 3x drizzle in another stack which should sharpen detail.
    Focus is difficult with a camera lens ..very sloppy. The cloud is rolling in so maybe no imaging tonight.
    Alex
     
  22. Xelasnave.1947 Valued Senior Member

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    not flash but not unexpected
    alex

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  23. elte Valued Senior Member

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    how many light years away are the star cluster and the galaxy
     

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