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Astrophotography: A beginning.

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  • #2605
    ravnostic
    Participant

    Hope this link works. My first truly stacked-and-composed image. The polar mount is sublime. My skilz…well, I’ll make progress. This is 8 hours effort. I feel like I gave birth, and it’s exhausting. But, looking at the result, I might get impregnated again…

    http://fossilspringsaz.com/pics/2012/feb/19/finishedherm2.jpg

    FYI//no, those aren’t hot pixels top center. The new body *does* have them. But these are 30-60 pixels in the full-res. That’s just what’s there (my choice of saturation and tone play their part, of course…)

    #45370
    lokisbong
    Participant

    Very cool Man!

    #45371
    Farktographer
    Participant

    …whoa

    #45372
    linguine
    Participant

    nice

    #45373
    chupathingie
    Participant

    Oh my… that’s gorgeous! By all means, re-impregnate.

    So spill the beans: number of exposures, duration, ISO, procedure, etc…

    Looks like you nailed the focus (that’s a lot harder than folks realize) and your scope’s color correction is very tight… no halos.

    What did you stack with? Did you shoot darks? There are a few hot pixels, so I’m guessing no darks…

    AND…. M42 is a magnet for satellites, ain’t it? 😆

    Is this full-frame or a crop?

    This is a seriously good first image… You should be addicted after this. None of my images look this good, even considering I’ve only shot wide-field sans scope, but now I have something to shoot for 😉

    #45374
    chupathingie
    Participant

    gotta add: the core is not overblown…the Trapezium isn’t lost in the brighter parts of the nebula.

    Red is emission, hydrogen gas excited by the ultraviolet from “nearby” stars; blue/grey is reflection, gas and dust illuminated by, or obscuring light from, the stars in the area. Very nice, it’s easy to see the 3d nature of M42 in this image…

    #45375
    Plamadude30k
    Participant

    Red is emission, hydrogen gas excited by the ultraviolet from “nearby” stars…

    Red is, in fact, H-alpha emission, which is the 3-2 orbital transition which produces light at ~656 nanometers. Orion is, in fact, an HII region, where all of the hydrogen is ionized by UV continuum photons. The size of these regions can get up to about 70 parsecs across! (sorry for the rambling, we just did HII regions in my ISM course. I never thought I’d know so much about dust and gas.)

    Anyway, amazing photo, Rav. This only galvanizes me further to get a tracking mount.

    #45376
    chupathingie
    Participant

    ohshit…don’t get me going… a parsec is likely the most obtuse measurement ever conceived… it’s practically arcane, but roughly equal to about 3 1/4 light years. The nearest star to Sol is about 1 1/4 parsec. I’ll leave it up to y’all to gather scale on that. Do a wiki to get the definition, it’s an odd standard for measurement, but a standard it is nonetheless.

    #45377
    fluffybunny
    Participant

    1 parsec = 6.022 ? 10^23 cubic hectares per decimeter-second ?

    #45378
    orionid
    Participant

    -insert jealous rage post here-

    /edited cuz bbcode eats brackets.

    #45379
    ravnostic
    Participant

    Responding in reverse order:

    orionid: you could always leave Kestrana and join me in a life of debauchery in the western deserts. There would[/b] have to be a tele-photo lens-pre-nup., but elsewise, I’m yours. 😉

    Fluff; I think you’ve got it, but I didn’t check the driver’s manual due to poor lighting conditions…

    chupa; the parsec is practical, for all earthling intent and purposes! It’s like the gold standard–we go off that, and everything will fall to hell! (see? look around our economy and tell me different!)

    //no, don’t–I don’t want to delve into politics here!!

    The details: 3 light frames @ approx 2 minute exposures (I counted in my head, fell short a few seconds in each), 1 dark frame same length, one very underexposed frame that I painted in via Elements to bring out the Trapezium. But even the SOOC of any one of the light frames is worthy and will see a farktography contest one day, I suspect (unless I do better). The first frame captured the satellite on the right side. As I oohed and aahed over it it crossed the nebula, the second frame saw it’s exit. Third didn’t have it at all–but that’s the way the stack stuck.

    Plama, get the tracking mount! I couldn’t be more pleased! I am amazed at the difference in my photos, after just one session! I had to realign some 8 or so times during the night, but only because I had to crank on the engine in my truck to provide a heater to keep me from hypothermia. Fortunately, once polarized (so to speak), retracking was a ‘breeze’.

    I’m considering, since I’m going to have it repaired anyway, converting my original xTi to infrared, so I can get more nebulosity. Hell, I’m not even considering it–it’s pretty much a done-deal in my head.

    Thanks, linguine, Farktographer, and lokisbong!

    Can’t wait to get knocked up again!!

    #45380
    ravnostic
    Participant

    Oh my… that’s gorgeous! By all means, re-impregnate.

    So spill the beans: number of exposures, duration, ISO, procedure, etc…

    Looks like you nailed the focus (that’s a lot harder than folks realize) and your scope’s color correction is very tight… no halos.

    What did you stack with? Did you shoot darks? There are a few hot pixels, so I’m guessing no darks…

    AND…. M42 is a magnet for satellites, ain’t it? 😆

    Is this full-frame or a crop?

    This is a seriously good first image… You should be addicted after this. None of my images look this good, even considering I’ve only shot wide-field sans scope, but now I have something to shoot for 😉

    Further reply: 3 light frames, 1 dark, 1 underexposed; no hot pixels–the dark frame took care of them, but there are them stars that just came out ‘red’, 20-40 pixels across (in some online processed images they aren’t so red, but there’s plenty online that do, which is how I reassured myself it was okay–and I planned on using elec. tape to recreate the star points you see in the Hubble shots {because of the mirror mount apparatus} but I forgot to bring it this time).

    ISO 1600 (gawd, I love the noise levels the T2i hides!), ~2 minutes each; focus courtesy of my home-made Bahov-whats-his-name mask (which I love-love-love for it’s accuracy!! In fact, I kept a couple shots from using it because the lines are so cool!).

    Full frame–we don need no stinkin’ crop! (In fact, if I could get a wider view, I would–and rather than buying a long lens, I may just opt for the $800 kit to convert the scope to a f/2 not a typo [ with a much wider view! approx 2-1/2 degree]) Should I? I think I shall… 😀 Prepare yourselves; I’ve seen images–to. die. for.

    There was CA–I ‘shopped it out on the affected stars (the brightest 10 or so). Telescope lenses usually combine red-green; the blue suffers. 🙁 (at f/2 ironically, this won’t be a problem)

    Stacked via Deep Sky Stacker. Which turns out to be a bee-ach to use, but I muddled through, and I’m glad I did. Yet the masking in Elements was far more difficult to master.

    Here’s a couple more shots, much closer to SOOC, and usable in future contests:

    Orion, Taurus, and the Pleiades:

    http://fossilspringsaz.com/pics/2012/feb/19/wedge20120218_007.jpg
    (large file–and with light pollution, but still way-cool for the number of stars, approx. 2 minutes; I like the pollution as it makes me feel I’m looking over the sun’s horizon at the scene)

    Sunrise (yes–Sunrise) via the astrozap filter:
    http://fossilspringsaz.com/pics/2012/feb/19/wedge20120218_004.jpg

    If you think DOF is a bitch at 300mm, try 2800! But you can, even through the clouds, see a couple sunspots–there isn’t much activity at the moment, unfortunately. I did like the atmospheric ‘waves’ in this shot.

    The moon a week earlier, no wedge-mount, but didn’t need it (huge file, 2.5 mp, sorry!) Saturation at 400%–there really are colors on the moon, I wanted to bring them out:
    http://fossilspringsaz.com/pics/2012/feb/19/ww2012_19.jpg

    The moonrise, counterpart to the cloudy sunrise shot (though the moon is a bit dimmer so the clouds had a grander role to play):

    http://fossilspringsaz.com/pics/2012/feb/19/WW2012_22.jpg

    I think for the next couple months I’ll either archive dive or skip contests–I hate to say this is way more fun (because it’s not, it’s just different–and I’m not embarrassed to say I’m way more into it at this time for not just the novelty); my loins are girdled with the new toy, and I’m definitely going to use every opportunity to capture what I can! I haven’t even done the planet stacking yet (I chose Jupiter)!!

    Thanks everyone for the kudos! More to come! Yes indeed!

    #45381
    orionid
    Participant

    really making me wish i had time to clean and play with the old newt in the garage. hey, there’s no magic this weekend, maybe I’ll do that friday.

    /and hand-make a bhatinov mask.

    #45382
    Plamadude30k
    Participant

    ohshit…don’t get me going… a parsec is likely the most obtuse measurement ever conceived… it’s practically arcane, but roughly equal to about 3 1/4 light years. The nearest star to Sol is about 1 1/4 parsec. I’ll leave it up to y’all to gather scale on that. Do a wiki to get the definition, it’s an odd standard for measurement, but a standard it is nonetheless.

    If you think that’s odd, try doing astronomy in cgs (centimeters/grams/seconds as opposed to MKS, meters, kilograms, seconds). Insanity. Also the standard units of astronomy to this day for stupid historical reasons-we still use ergs. Even wolfram alpha thinks ergs are a deprecated unit.

    Parsecs are actually incredibly useful for astronomers, though. The definition of a parsec is the distance to an object that shows the parallax angle of 1 arcsecond given a baseline of 1AU.

    Okay, maybe that didn’t help. Uh, well, it’s defined by geometry using the earth’s orbit and the distance to an object.

    Hmm. Okay, yeah, it is a bit arcane. Sorry. I should have just said “HII regions can be really frakkin’ big.” and left it there. Of course, that’s ignoring the Ultra-compact HII regions, which are sub-lightyear sized, and all the intermediate variation.

    But I digress.

    Rav, how did you make your flat frames? Did you take any bias frames (meaning 0 second exposures with the lens cap on)? And how’d you make the Bahtinov mask? I’d like to try one myself.

    #45361
    ravnostic
    Participant

    Orionid; I copied PDF’s from on-line, had them printed and laminated at Kinko’s (kinky, eh?), and cut one out from there (saving the others as spares–total cost about $2.98 for three, you should do better as your glass doesn’t require 11×17 sized paper)). Here’s a picture of what I see when I’m attempting focus:

    Here’ the focus is a little too far, and I need to tighten. For those who haven’t used one, the central ‘spike’ moves perpendicular to the ‘x’ spikes, the goal being centered. With this orientation, I’m too far out of focus (yes, you can do this with a telescope), but by turning the focal knob I can bring the central spike down to where it is perfectly centered between the ‘x’ spikes, and that’s the focal goal.

    Science is funz! And it can be cheap! And gawd knows, I like cheap…

    Plama, man if I could lug a 120 lb rig to Hawaii, I could nearly afford it right now!! But ain’t gonna happen!! (I want the f/2 rig; I’m certain; money better spent.)

    Please continue your digression, I was just getting into it!…

    I didn’t do flat frames (I didn’t know!!), but I did take a dark frame, more or less the same time as the others, to eliminate noise (I think it worked!). It’s fortunate that O’s neb is so bright on it’s own that it doesn’t seem I need all them other frames (i.e., I dunno wut I’m doing so I’m playing the fiddle by ear!)

    The Bahtinov mask is easy; downloaded a PDF. I actually used one for a 7″, as it fit on an 8X11, and enlarged it to fit onto a 11X17. I had to figure out the 2ndary mirror point and diameter, but elsewise, a craft knife did the work. It’s just laminated paper–but if it works–go with it!!

    (next time, I’ll remember to bring the electrical tape, to simulate the spikes we see from Hubble shots caused by it’s 2ndary mirror.)

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