Astrophoto-op :Got it! (Moon, 1% full 26 hrs old)

[ravnostic]

The very small (1%) crescent moon will be near the very bright (-3.5 mag) Venus this evening. Venus will be 10 degrees above the horizon barely to the left of it (more-so if you’re further north, but not significantly so unless you’re in Alaska or something), and if you just get your infinity focus correct, it should be an easy subject to pick out at full res). It would appear as a small dot of white light. Given it’s proximity to the moon, this is a perfect shot to go for for the Astrofarktography contest next week.

The trick? The contrast between moon and sky will be near-nil, and seeing conditions near the horizon, especially in polluted areas, may make it impossible. But give it a go! Weather permitting (they claim here it will rain, but they’ve also claimed weather all week that hasn’t panned out), I will, I’ve even scheduled 2 hours vaca time so I can go into work late.

If you’d like some help, here’s what settings I’ll be using, starting immediately after the sun goes down:

**f/11 or 14 (I’m be using my 300mm and it’s sharpest in this range; use a setting 2-3x the most-open aperture if you have faster glass; should result in the sharpest image assuming focus is good).

**Remember the rule of 600, which for picky people like me is the rule of 480: divide your effeftive] lens length into either number you prefer and that’s your maximum exposure. This close to sunset you likely won’t hit it before the moon sets (40 min. after sunset at 30 deg. N. latitude, about 50 when you hit 45 deg. or so) if you use Av priority. In my case, I shoot with an APC sensor, so I have 480mm effective, I don’t shoot over a 1 second exposure.

**You may wish to bracket +/- 1 on the Av; contrast will be very close to nil and multiple exposures may be useful (it’s astrofarktography; stacking is permitted!).

**Use as low an ISO as possible, likely 100 just after sunset to 400; if you have to hit 800 I’d be surprised.

**Use mirror-lockup; if you have a remote shutter release, use it after waiting a few seconds for mirror vibrations settle, or shoot with a 2-10 second delay (the mirror will lock when the timer starts; better to go with 5-10 sec than with 2 if your camera will let you do so)

**Venus and the moon will follow to where the sun hit the horizon, so keep that spot in your frame to the lower right!!

Good luck if you get it! A 1% lit moon is a *tough nut to crack* (my best, thus far, is 2%) Do not expect great detail in the moon; this close to the horizon the atmosphere will distort things and except by shear chance, you’ll probably get a squigly curved line, if anything at all. Maybe it will be contest worthy, and maybe it won’t, but it will be a neat exercise in catching a rarely seen sight, the moon, just 24-27 hours old (if you’re in the US) Younger moons have been seen, but with the moon at it’s furthest in it’s orbit, it’s moving kinda slow and will still be very very thin.

/edited by Orionid to fix the date in the title. (reedited by ravnostic to change title

[Yugoboy]

Damn. Yesterday I sent the SLR in for tune-up.

Good luck y’all! Looking forward to seeing what you dudes and dudettes come up with next week. I put a couple things together from last summer, but I just know that whatever I throw up is going to get blown off the map by the stuff you guys can come up with.

[CauseISaidSo]

Very much appreciate the heads-up, rav, although I won’t be able to take advantage of it. Just too much going on right now to get out and shoot so I’ll be skipping this Farkstronomy.

[orionid]

Work :/

[nobigdeal]

Clouds 🙁

[ravnostic]

Scattered clouds here, too, NBD …but the western sky seems clear! Looks like if I can get this, I won’t be facing a slew of others with prettier foregrounds I guess!

[ravnostic]

So I got it. Then came straight to work. I just picked a frame, found it, did some contrast stuff, cropped, and posted. I don’t have photoshop or stacking tools on the old laptop I took with me. In the morning, I’ll look through the frames to find the ‘best’ shots and see what I can do that’s better, but for a first look, it’s here: https://plus.google.com/u/0/107857888121727893520/posts/QXPHmGJt5wE

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