Skip to toolbar

Some recent astrophotos

Forums Forums Farktography General Chat The Gallery Some recent astrophotos

Viewing 15 posts - 1 through 15 (of 45 total)
  • Author
    Posts
  • #2188
    Plamadude30k
    Participant

    Hey everybody-I’ve been at telescopes a lot this summer, and as such I’ve had plenty of opportunity to experiment further with astrophotos. Since the weather is making it look unlikely that I’ll get many more, I thought I’d post a few of my best here for you to (admire/critique/ignore: choose one):

    The Kuiper 61″ Telescope & Milky Way:

    Kuiper 61″ and Spacewatch Schmidt Telescopes:

    Vertical Pano of the Milky Way above the Kuiper 61″ telescope:

    Meteor(s) above the Bok 90″ Telescope (Kitt Peak National Observatory):

    A gallery of a few more of my favorites is here.

    #36827
    orionid
    Participant

    I like the perspective of the first one. It feels like I’m right there with you.

    #36826
    Yugoboy
    Participant

    I did my first experiments doing night sky photography last night.

    Had trouble getting the moon’s details, but I did manage to get most of the big dipper. I think I need to go out into the countryside and away from the local light to get really nice shots like yours.

    (Probably should also use wide angle lens, and should definitely learn how to use the longer than 30 seconds shutter options (if I have any that don’t require investing in a remote control).

    Yours sure are purty… (mild jealousy is trumped by aesthetic awe).

    #36825
    Plamadude30k
    Participant

    How’d the experiments go? If need to feel better about yours, I could probably dig up my first attempts at astrophotography-they were hopeless.

    Getting away from light pollution is always a good idea, and unless you have a motorized tracking mount, you’ll want a wide-angle lens, the faster the better. I’ve been going back and forth between my 18-105 mm f/3.5-5.6 set at 18mm, f/3.5 and my 28mm f/2.5. The 28mm is WAY faster and has weirdly awesome saturation/color reproduction, but is optically…crap. The 18-105mm is a great lens, but for some mysterious reason, I’m never 100% satisfied with the astrophotos that come out of it.

    As for getting exposures longer than 30 seconds, if you have a nikon, you’ll almost certainly need a remote. The ML-L3 is the one I use-cheap and effective. You can also take a bunch of shorter exposures and stack them-I think there’s some free software for that floating around on the internet.

    #36824
    Yugoboy
    Participant

    How’d the experiments go? If need to feel better about yours, I could probably dig up my first attempts at astrophotography-they were hopeless.

    Getting away from light pollution is always a good idea, and unless you have a motorized tracking mount, you’ll want a wide-angle lens, the faster the better. I’ve been going back and forth between my 18-105 mm f/3.5-5.6 set at 18mm, f/3.5 and my 28mm f/2.5. The 28mm is WAY faster and has weirdly awesome saturation/color reproduction, but is optically…crap. The 18-105mm is a great lens, but for some mysterious reason, I’m never 100% satisfied with the astrophotos that come out of it.

    My wide angle’s the 18-55 kit lens. It’s a Nikon and has VR, so I’m confident it’ll be OK for practicing for now. My college job is at an annex way out in the boonies of western NY, so I’m planning on stopping on a quiet stretch of road on the way home tomorrow to give it another go. I’ll probably pack my ancient tripod due to the fact that it’s WAY heavier than the Slick I’ve got for daily use.

    As for getting exposures longer than 30 seconds, if you have a nikon, you’ll almost certainly need a remote. The ML-L3 is the one I use-cheap and effective. You can also take a bunch of shorter exposures and stack them-I think there’s some free software for that floating around on the internet.

    The remote’s out of the question for now regardless of how inexpensive. Until school starts back up we’re on a tight budget (we’re behind, and my wife’s working lots and lots of OT just to try to get us to even. We’re losing almost 2 weeks of earning when my parents take us to Italy in August. It’s a trade-off we’re happy to make… but no scratch for any extras). I’ll have to write down the model number and put it on the Christmas list.

    As for “stacking”… I’ll have to look up whatever that is. I’m a Photoshopper… my photography experience is largely about what I can get in the viewfinder. I’ve been playing around a bit with HDR, but nothing I’m happy with yet.

    Never fear… I’ll give the astrophotography some more tries before giving it up.

    #36823
    Plamadude30k
    Participant

    The 18-55mm is an okay lens-it’s what I started with (though mine wasn’t the VR version). The focus on it is excessively fiddly, though, and if you’re not extremely lucky the focus will be noticeably off. Sadly, skill and experience has almost no effect there. You basically just guess. Equally sadly, you’re probably not going to find too many better wide/fast lenses for a nikon unless you’re willing to spend $$$$ to $$$$$. Trust me, I’ve looked.

    As for the remote, it’s super simple-you could probably build one. Basically an IR led with a button to turn it on. There’s no coded signal on it either-I’ve managed to set off my camera by igniting magnesium shavings from my backpacking firestarting kit using just a knife and steel.

    #36822
    ravnostic
    Participant

    Nice shots, Plama.

    While I was down in Cochise County this weekend, I went for some astro pics (in part), but the cloud cover was too much to overcome (seems to be a theme when I go to dark-skied areas). Not that I’m unhappy with the lightning I captured–but those teasers of galactic views were just that: teasers. Enough to remind me of the shots I didn’t get. 🙁

    #36821
    Yugoboy
    Participant

    As for the remote, it’s super simple-you could probably build one. Basically an IR led with a button to turn it on. There’s no coded signal on it either-I’ve managed to set off my camera by igniting magnesium shavings from my backpacking firestarting kit using just a knife and steel.

    OK… here’s a project for the builders here… can you build a remote with a dollar-store universal remote?

    #36820
    ravnostic
    Participant

    Orionid can probably build one from a toilet paper tube and some tin foil. 😆

    #36819
    orionid
    Participant

    My buddy did just that for a sony alpha. Turns out, the pre-programmed remotes are coded signals, not a solid, high-density IR beam, so your best bet is an IR LED from Radio Shack, a button, and a 3V (or whatever the nominal LED voltage is) battery. It’ll run you about $8 total, which is comparable to a cheap hong kong trigger.

    #36818
    Yugoboy
    Participant

    I’ll look into that. Thanx!

    #36817
    Plamadude30k
    Participant

    While I’m at it, I figured I’d post the results of my experiments with different lenses for astrophotos. Both of these photos were taken from the exact same place with the exact same camera settings of:
    28mm, f/minimum (either 2.5 or 4), 20 second exposures, ISO of 400. The exact same (minor) postprocessing was applied to both. Let’s see the results.

    Image 1-Vivitar (actually made by Tamron) 28mm f/2.5 prime:

    Image 2-Nikkor 18-105mm f/3.5-5.6:

    Clearly the faster lens is brighter, and personally I think it has excellent color reproduction. If we zoom in, however, we can see the real differences:

    Vivitar, zoomed:

    Nikkor, zoomed (same region):

    So, yeah. Chrom. Abb., coma, possibly spherical aberration, maybe even some astigmatism, though it’s worth it to note that astigmatism is difficult to diagnose here since everything else could easily mask it. In fact, there’s some really interesting field curvature and off-axis things going on elsewhere in the image-mostly REALLY strong chromatic aberration. Thankfully it’s not bad enough to notice on a computer screen/zoomed out image, but I wouldn’t want to print it. The Nikkor, on the other hand, is optically good enough that my focus and star movement is worse than any possible flaws in the optics. Weirdly, I think I actually had better focus on the 28mm. I guess that’s the difference between a $400 lens and a $40 lens.

    #36816
    ravnostic
    Participant

    Yeah, example #1 closeup–I’m there. I need better lenses. Fine for online posting in moderate sizes, but closeups? Fugetaboutit.

    #36815
    CauseISaidSo
    Participant

    My buddy did just that for a sony alpha. Turns out, the pre-programmed remotes are coded signals, not a solid, high-density IR beam, so your best bet is an IR LED from Radio Shack, a button, and a 3V (or whatever the nominal LED voltage is) battery. It’ll run you about $8 total, which is comparable to a cheap hong kong trigger.

    Yep, IR remotes use a modulated signal in the 38-40kHz range.

    When building your own, don’t forget a resistor or your IR LED will likely live a bright but very brief life. Use Ohm’s law (R=V/I) to calculate the resistor size based on the battery voltage (V) and maximum current (I) of the IR LED.

    #36814
    Plamadude30k
    Participant

    My buddy did just that for a sony alpha. Turns out, the pre-programmed remotes are coded signals, not a solid, high-density IR beam, so your best bet is an IR LED from Radio Shack, a button, and a 3V (or whatever the nominal LED voltage is) battery. It’ll run you about $8 total, which is comparable to a cheap hong kong trigger.

    Yep, IR remotes use a modulated signal in the 38-40kHz range.

    When building your own, don’t forget a resistor or your IR LED will likely live a bright but very brief life. Use Ohm’s law (R=V/I) to calculate the resistor size based on the battery voltage (V) and maximum current (I) of the IR LED.

    That’s really weird-I could swear my camera triggered in remote mode when I lit the magnesium shavings. I’m going to try it again.

Viewing 15 posts - 1 through 15 (of 45 total)
  • You must be logged in to reply to this topic.