Some photos

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

  1. Xelasnave.1947 Valued Senior Member

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    Yes we call it a mosaic...as I mentioned maybe next year as I doubt I can fit it in before it's gone.
    But it is a lot of work.
    I have not been doing all I should at the moment actually.
    Let me take you thru what is involved.
    It is a cooled mono camera...so say with this image...say 90 one minute exposures or similar time but using longer subs which I will do when the observatory is complete ( I am really only playing around at present) but that is 90 subs thru each of 7 filters...and each filter group needs say 40 dark frames ..you can use the same 40 if you don't change your gain settings ( that's like ISO on a DSLR) , you also need say 40 flat frames taken for each filter to remove any dust spots etc in the optical part and these are specific for each filter , bit of work right there, and these flat frames should have their own dark frames a other 40, and in addition you need 40 bias frames ( like a dark frames but short exposure) and I am really not sure what they fix, each filter group needs to be stacked all 7 groups. So your 90 light frames, your 40 dark frames, 40 flat frames, 40 dark frames for those flat frames and 40 bias frames, are stacked using one frame as a reference to have every thing line up the same..so after stacking you have 7 individual stacked images Red blue green luminance Ha, O11 and S11. ..each is separately processed in a program called star tools, where you crop them all to remove stacking artifects due to the frames being a little out of wack with each other, each process take about an hour, so seven hours approx...often longer... then you take these seven images to Photoshop. I make a duplicate of each so I am usually working with 14 by now....now at this point they are all just black and white so you colour map each of the seven by making the black and white blue image a blue image, the black and white red to red etc..HA you may make it brown red or green, O 11 colour to blue S11 say yellow...you follow a "palette" the most popular being the Hubble Palette. ..in photo shop you first adjust things like exposure, brightness, contrast etc for each of the seven and maybe up to the fourteen..then you use the layer feature to slowly combine all 7 images into one image ( maybe you bring in a duplicate that you have adjusted to bring out a feature)...in photo shop do things to like brightness, contrast, haze removal, colour balance, use the rubber tool and combing two images to merge and bring the better features of each together..the dive tool to brighten selected spots and the burn tool to darken certain areas ...I then take that completed image to Gimp for a minor level adjustment further brightness and contrast adjustment and a resize (downsize) to be able to post it here or my astronomy forum to which I belong.

    Now to do a mosaic you need in this case at least three times what I have been thru but nine would be better so that little galaxy ( not in this one I posted) would present well balanced. Many many hours of involvement.

    Stacking each filter group can take a couple of hours. Once I stacked 230 DSLR large frame (24 meg) and it took 10 hours.

    I am using a feature in the stacking software that was designed for the Hubble ..."Drizzle" it increases the image size to get more detail that results in each stacked image (7)being 1.6 gig...because they are so big I crop the image to remove overlapped borders but also to reduce the image but also use a process to cut each image to 25% of its original size.

    By the time they go to photo shop they may be down to 50meg but I have had them much larger.

    And that is the entry level approach... it gets a little more complicated if you say use more expensive software...I am just starting out you see.
    Alex
     
    Last edited: Oct 30, 2019
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  3. Xelasnave.1947 Valued Senior Member

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    Those we call a wide field...you use a DSLR and any lens from 18 mm focal length to ..I have a 300 mm which is almost up to my 80mm scope that has a focal length of 400mm. The photo up a bit with the Lagon Nebula is a wide field...
    your ordinal camera lens that comes with the DSLR will do great wide field..I love them
    Alex
     
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  5. Write4U Valued Senior Member

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    Assembling one photo with a great number of parts. Awesome! It sounds like an artform to me, a form of painting.
     
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  7. Truck Captain Stumpy The Right Honourable Reverend Truck Captain Valued Senior Member

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    I took a picture of my 'pecker in the front yard... this is as talented as I get

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    the Pileated Woodpecker. This one is quite large! I guess the height at 18 inches as he isn't keen on letting me measure him. There are two others that regularly argue over the dead hardwood I keep for their dining pleasure, but they take off when this beast is around.
     
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  8. Xelasnave.1947 Valued Senior Member

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    I was not happy with my earlier images so started the processing all over and really tried to do better...I am happier but not sure if it still has too much purple..I am colour blind which stuffs up my colour merging...so is it purple or blue?

    alex

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  9. Seattle Valued Senior Member

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    Nice! We had many woodpeckers where I grew up (N.C.) but they were the small kind. I knew about the cartoon character, Woody Woodpecker but I didn't know there were any that really looked like that as the ones I saw certainly didn't.

    As an adult I was hiking though the woods in Canada (B.C.) and I saw one like the one in your picture and realized that "Woody" really was modeled after a real woodpecker. They are cool looking. I wish they were more common as I've only seen the one.
     
  10. Xelasnave.1947 Valued Senior Member

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    8,185
    I have learnt that the colour in that last one is off also...I guess I will have to do it all again.
    Alex
     
  11. Truck Captain Stumpy The Right Honourable Reverend Truck Captain Valued Senior Member

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    there are many different kinds - this is just one type I have in the yard, and usually, the biggest and loudest - their laugh is reminiscent of the cartoon to a degree as they sound like a maniacal escaped patient laughing through the woods (rather fun to watch, though). There is also the red-headed woodpecker, the Flicker, the occasional Yellow-Bellied Sapsucker, and a tiny little bugger called the Downy Woodpecker.


    if I can catch one of the younger twins in the yard I'll send it to you! LMFAO

    more purple, but a hint of blue - rather liked that pic! I might steal it and twitter it later, with your permission (and I'll make sure you get full credit, mind). I have a few folk who might really enjoy that pic.
    let me know!

    the following pictures are compliments of: NASA, space.com, and exoreplanets twitter feed

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  12. Xelasnave.1947 Valued Senior Member

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    Sure granted but you can find much better out there that have correct colour..maybe you could take it into photo shop and adjust it and present it as our combined work.
    I expect I won't be around for a while so you behave yourself now. Goodbye.
    Alex
     
  13. Truck Captain Stumpy The Right Honourable Reverend Truck Captain Valued Senior Member

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    the point isn't to find better photo's - it's to share your work with like-minded enthusiasts taking astronomical photo's, like in this thread. I don't have a talent for it (or the patience, or the money), but I can admire good pictures! And I have a few friends that also like a good astronomical pic...

    fire season?
    I hope all is well with you

    Take care!
     
  14. Xelasnave.1947 Valued Senior Member

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    It is a great hobby to learn patience and lots of stuff really and you will learn how to save your money like never before...It took me years to bank roll my gear. Cutting right down on take away food, not going to the pub only buying food that was on special...buying on special before I needed something that sooner or later would need..not good at the time but I bought a generator that I did not need on special for two hundred bucks two kVA well yesterday my old Genny expired...now I know that I would have to pay six to seven hundred if I had to have one today...which I do...so that two hundred dollar purchase in effect has put me near five hundred ahead of the game. Takeaway food was a grand a year, the pub probably two or three grand. Groceries I recon my approach saves me fifteen hundred a year.
    People think I am a Scrooge and rolling in cash but I bet few have as small an income as me...I just make it go twice as far...the recent scope I got was no more than a years saving on groceries by being timely.
    It is... but completing projects, tidying up stuff, and on a get fit thing.

    I find I get too involved sometimes on the net and it starts to interfere with my busy routine is all... Look at that something from nothing thread a...waste of time ..I need to devote my rest time in asking questions about my hobby...how not to get purple in my image..that sort of thing...and like this morning ..even with a crook ankle have poured two small bags of concrete...only here now because I needs to rest.
    Probably all day but I am going to read up on RBG colour processing.
    The reason I have been on a lot in the last week is I have been on my back resting the ankle.
    I will be back as time permits.
    Alex
     
    Last edited: Nov 1, 2019
  15. Truck Captain Stumpy The Right Honourable Reverend Truck Captain Valued Senior Member

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    well hell, that is how I live now! LOL
    It took me years to bankroll my gear as well... but it's not photography gear.
    HOLY [BLEEP] ON A [BLEEP] SANDWICH!
    My "takeaway" food, or "not at home restaurant food" is a whopping US $ 20 a month, and that is with tip! (Local Chinese Restaraunt is amazing and cheap - local being relative given that it's an hour away and we will hit it on the way back from paying bills)
    !!!!

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    !!!!
    Man, the cost of living around your place has to be high!
    I could buy two acres of prime woodland within a 1/2 mile of town with that amount of money around here!
    Wow!
    I bet we're not so different, you and I. Although I may well have a considerably smaller income.

    I did pick up a nice spotting scope on the cheap - it's a 20-60x60AE like the one I linked, but I only paid 50USD for it, plus 10USD shipping.

    Well, don't feel obligated to answer all my above. I'm just chatting until I head to class anyway.


    I've nothing but time, usually. I'll see you whenever you post to the thread or reply to this.
    PEACE

     
  16. Xelasnave.1947 Valued Senior Member

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    I think the cost of living is probably much higher than in the US..I paid one dollar sixty a litre for petrol yesterday at the country shop..in town it rocks between say one dollar thirty and one dollar fifty a litre.

    These days it would cost me probably a hundred bucks at the pub..and in truth even back then I could spend a hundred... meal, beef jerky and chips maybe some chocolate..heck it was a once a week thing..all week not seeing anyone at all...so it was full on...It was usually a break eventhing overall cause I would more often than not win the pool comp which got me from fifty to a hundred bucks..plus the night you win you get a few ten dollar games in before closing..but at that time of night I am into the black zambuca( one each game) which back then was five bucks a nip plus often a beer on the side from wins where the bet was a beer...would be more than five bucks for a black now... mmm I really wouldn't mind a bottle right now...mmmm...but not driving 45 minutes to buy a bottle and the closest pub would not even know what it was..... but I don't lose control when I drink a lot (because of the control freak thing I guess) whereas the other players by the end of the night could hardy stand up so at that time of night the money poured in..usually five bucks and a black each game..but some only a beer...I was into it cause I like the game..its like chess the way I play it...andwhen I had my eye in I would make short games to make as much as possible before closing. And no I did not drive home as there was always a party somewhere I would go there play guitar and drive home the next day...it was only once a week... but when I turned 70 I decided to save harder and buy some astro imaging gear.
    TYhings take more time because of my legs, lifting even simple things becomes a block and tackle deal... building my second observatory in the city (the current build is my third) was worse than climbing Mt Everest..something that once I would knock up in a weekend would take me a week to get each wall panel up the stairs..like this thing at the moment...the ankle wasn't so much of a problem cause I could sit down and spoon the dry mix into the box...but just that wore me out...so even if the ankle was fine I would be off the site until about now...If the ankle was ok I would do another two bags around sunset...

    and PEACE to you.
    alex
     
  17. Xelasnave.1947 Valued Senior Member

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    8,185
    So resting is no time to stop doing stuff so I decided to do a reprocess of the data used to complete the above image. I was told it was purple and green but apparently not on my monitor..anyways because I was told it was purple I had to reprocess to do better.

    So here is a quick process...only four hours ...I am not sure..after a while you lose all objectivity..but I think it is better than the last one...and I would be interested for anyone who is prepared to take the time to tell me what the colours appear to be on their monitor..just curious.

    alex

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  18. Xelasnave.1947 Valued Senior Member

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    I think the lappy has a problem as it looks green here..to me..on the lappy yellow
    Alex
     
  19. Truck Captain Stumpy The Right Honourable Reverend Truck Captain Valued Senior Member

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    Holy jesus wearing stiletto heels and fishnet on a pogo stick! I've taken the whole family out for a meal locally without breaking a hundred bucks! My wife and I, Daughter, and three teenage grandkids!

    just take care of yourself!

    a great thing, too, because people are enjoying the pics!

    I'm seeing a lot of yellow in the middle but purple-ish with a hint of blue at the edges.
    My wife loved it! (Yellow is her favourite colour)
     
  20. Xelasnave.1947 Valued Senior Member

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    Thanks I think that is the way it should be.
    My favorite colour is yellow but I never wear yellow clothes or buy a yellow car but for whatever reason I like yellow in my paintings.
    Just starting my day...lots to do.
    Alex
     
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  21. Xelasnave.1947 Valued Senior Member

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    Already used a bag of concrete.
    Alex
     
  22. Xelasnave.1947 Valued Senior Member

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    Not easy doing all this sitting down but what else can you do with a busted ankle..it's been over a week and I can only rest...but I have learnt to do so much what sitting...so I set both piers in the observatory in concrete I also drove five short star pickets into the clay under to add grip to the ground... Lots of concrete.. I used a dust pan and could only manage about 2 cups each time ..put it in dry and added water after...not the way I like to do it but it will work..does not need to be serious strong mainly just heavy and stable..it is both

    Alex
     
    Last edited: Nov 2, 2019
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  23. Truck Captain Stumpy The Right Honourable Reverend Truck Captain Valued Senior Member

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    just forwarding some information you may be interested in from Phil Plait
    he writes the Bad Astronomy blog
    "The Bad Astronomy blog is all about real-world science — it covers the entire Universe, from subatomic particles to the Big Bang itself."
    https://www.syfy.com/tags/bad-astronomy
     

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