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AstroAndy

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Image Comments posted by AstroAndy

    Moth (2)

          3

    I'm sort of a closet lepidopterist (the branch of entomology concerning butterflies and moths). Usually, in most cases, if they don't have feathered antennae, they're butterflies, and being active in daylight is a dead giveaway). There's one moth that looks more like a butterfly, which is the Atlas moth.

  1. NP..you have some good stuff there, you should have seen me starting out, I was literally standing beside my scope w/ a remote control for my camera timing 30 secs for the Andromeda galaxy w/out guiding.

    As time goes on, you'll get more and more used to it.

  2. Here it is..sorry about the wait, I couldn't find a way to put an image in an answer, so I made a album w/ this one img., so you can see it. Pls. let me know when you have looked at it, so I can delete this album again.

     

    Andy

     

    PS I also did a bit of noise removal

     

  3. Gradient removal takes out gradient, i.e. (uneven) illumination caused by light pollution and vignetting, basically, the "brightness" of the background (where it should be dark). It also takes out color gradient (color brightness which can go from red to green, all in one image,like e.g. red illumination from the guide cam into the imaging cam as happened to this genius << once :S ). It can also take out some noise (graininess), although noise removal is a different step. Normally, flats are taken in twilight (I do mine in the morning, after imaging, at about 1/180 -1/250 of a second, although one reads that maybe the exposure should be longer). One can also stick a white t-shirt in front of the imaging scope, hold a flashlight to it, and take "t-shirt flats" inhouse. There is another method which I use, and that is to create flats from either each image (a lot of work), or from a stacked, precalibrated image (less work). This is what I did w/ yours. Here are 2 tutorials of the methods I used:

    http://ccdastro.pwp.blueyonder.co.uk/gradient_removal.htm

    Shortly, I'll upload the 2 results I got, once I figure out how to get these imgs in here in the answer section.

  4. If my first attempts had been looking like that, I'd have been happy. :)

    As to curves and levels, they bring out highlights, midtomes, and shadows (bright, medium, dark areas in the pic).

    Curves are interesting because you can set points on them (with the eyedropper tool you can measure the darkness, brightness of things). I'm not an expert, but what I do is measure a dark point on the sky, set the value in curves (what you dio is click shift (or ctrl) when you are on the desired value, and have curves up, and it sets a point), then, set another point directly on curves, eg. my value is 10, then set another point @ 20). This "fixes" the darkness level, and you can cheerfully work away on img. details. I don't know whether I'm explaining myself well, maybe this helps:

    http://www.photoshopessentials.com/photo-editing/levels-curves/

    Clear skies.

    M27

          2

    Round stars, color info., structure recognizable, only a bit of gradient, seems like you hit all the right points,,especially for a first img (DSO)..as to PS, we've all been there, it'll come with time.

    phdgraph

          2

    It would be nice to know what equipment these settings go with, e.g. 9x50 finder scope, OAG (Off Axis guider, Mount and scope), and what the values actually are (on the graph / and in the brain settings). :)

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