[chupathingie]

Oh, just a reference you folks might find useful as a bookmark:
http://www.jshine.net/astronomy/dark_sky/

[chupathingie]

When you say “mount”, are you referring to a star-tracking mount (i.e., one that will automatically move to keep the celestial objects in the same position versus time)? Sorry if that’s a stupid question, but I’m more or less a complete noob when it comes to astrophotography.

Yup… tracking mount. The one I’m eyeing is overkill for just a camera and telephoto lens, but plans are to have a 10″ F5 to ride on it.

If you’re just planning on starting out with a camera and lens, google up plans for a “barn door tracker”; a relatively easily constructed cheap alternative. There really are a great number of objects that are huge in the sky, just too faint to see unaided and a zoom lens is more than enough to capture them. Better glass=better images of course, all other factors being equal. The andromeda galaxy for instance extends about 4 degrees, or 7-8 times the size of the full moon.

If you have a scope, a tracking mount is almost a must. I’ve seen some awesome images done with manual guiding, but the patience and endurance it takes to keep a guide star in one spot for several hours is more than I’m willing to attempt.

You’re only about 6 hours from me, maybe next summer we can get a weekend shoot together if I manage to get all my gear scared up. I’ve got some mag6 skies less than an hour from the house here.

Heck, with the folks in Phoenix maybe getting interested we could all converge in Albuquerque and set up in the mountains out towards Taos somewhere. There is some seriously pristine sky out that way.

[chupathingie]

I’ll have a car note paid off early next year, and I’m seriously thinking about making a mount and a 10″ conical a priority. I’ve been working up plans for a truss tube with a dovetail to mount to a GEM so that I can break down the OTA for portability. Now if I can find someone who can weld aluminum…

[chupathingie]

Swimming dog, sunset tree. I also like the skyline, but I’m drawn to HDR when it serves it’s purpose (and it does, IMO in that image, tho I think the saturation’s a bit high for a natural look).

I think I like the dog best of all, sharp focus and frozen action and the look on his face says he’d likely not fare well trying to chew gum while thinking of swimming…

[chupathingie]

I understand the bitchin’; been there, and damn near bald as a result LOL

Doing this manually in PS or an alternative is very tedious, but will get you to grips with the basics. Or you could blow $150 on Registar.

Registax you’re not alone with… it works well for AVI files of solar system objects (that’s what it’s designed for) but I’ve never had it exceed what I could do manually with darks, flats and data in a PS alternative.

Deep Sky Stacker and ImagePlus are another couple of programs I hear folks using.

All I use is the free stuff, and I’m running linux so the high bit-depth manipulator of choice is Cinepaint.

Samples:
http://www.flickr.com/photos/44012674@N04/sets/72157624734692512/
Yes, they look like shit. All but one was taken with a cheap 300mm on the original Digital Rebel back in about 2003 on an amazingly poor quality Edmund Scientific GEM from circa 1977. I’ve since graduated to a much better camera and better glass. Unfortunately, I still have Barney Rubble’s mount; so little else to show til I manage a better transport system for the camera. Also, these are the images I wound up with while just starting with digital AP. Don’t get discouraged. There is a LOT of technique to learn in this hobby, but what I managed was enough to hook me.

Take a series to stack (at least 20) some night, even on a cheap mount, and look me up on skype and we’ll toy with them… won’t take you long to see results.

[chupathingie]

ya know, I could do a write-up, but rather than re-invent the wheel, this guy:
http://www.covingtoninnovations.com/dslr/EOS300Dastro.html
has a pretty good write-up.

As far as software goes, that depends on your desired learning curve… software like Astrostack, Registax, et al automate a lot of things and work in high bit-depths. Don’t bother with any software that is only 8-bit. You need at least 16 bits per color channel to do any worthwhile level-stretching with astrophotos. 8-bit software will simply leave you with a heavily posterized image after only a few stretches or curves adjustments. Some of the software out there uses 32 bit float formats. You’re going to need a lot of RAM and as much processor as you can scare up. Expect images you take with a DSLR to consume 50-120MB PER IMAGE in 16bit. Double that for 32. You’ll be stacking upwards of 20-30 images for each final if you want them to look clean and sharp. Do the math, it’s quite easy for a project to consume several gig of ram while you’re working.

Automated software is available, and from what I’ve seen some of the most consistently beautiful results come from folks using IRIS, although some of the “easier” software still manage stunning images. IRIS has a steep learning curve, but it’s capable of accurately handling anything you throw at it. Professional astronomers (read: NASA, JPL, most major universities) use IRIS to process their images. Someday I’ll take the time… for now I’m lacking hardware (the droolworthy Losmandy) and the time to make the effort. Someday *sigh*.

Arm yourself with some 16-bit manipulation software. Cinepaint for Linux and Mac (free). You’ll have to google for what’s available in windows, I’ve been off that money treadmill for a couple years now. Photoshop of at least CS2, but there are others that will allow editing/layering in 16bit out there. You’ll use it for more than astro stuff, working in high bit depth works wonders for regular photography as well for expanding apparent dynamic range for example.

[chupathingie]

While the wife gets ready (after rushing me into the shower… 😛 ), the idea of noise reduction is to average the images together. the easiest way to do this is to stack all of your images (please shoot in RAW and stack the huge-ass TIFFs…although JPGs do actually benefit from this as well) in separate layers, then apply transparency to each layer in the following order: base layer=100%, second layer=50%, third layer=33%, fourth=25%, fifth=20%… in the fashion of transparency value = 1/layer# starting with 1 for the base layer. I stack in groups of five, so for 25 images you’d do this process twice… once with the originals, and again with the flattened results from the first set.

Keep in mind that you do this AFTER you apply darks (and possibly lights made with a lightbox or equivalent) to mitigate hot pixels and vignetting, respectively.

I’ll cover the basics there after dinner, hopefully. 🙂

[chupathingie]

OK, 6 minutes makes much more statistical sense.
CauseISaidSo, I can do a quick write-up on some basic stacking in Cinepaint (works in PS and others, same principles) but it will be later… been working my day off since before dawn and I need to run and catch dinner before they call me again (double-time, HUT! I’m a greedy little so-and-so).

[chupathingie]

According to the EXIF data attached to the image: 5D mkii, 6400ISO, f2.8, 16mm @30seconds. I can’t see any visible trailing in the stars or any artifacts from the landscape to indicate a stack of lights (doesn’t rule it out tho). The image is in Canon’s native 3:2 aspect, but it has been reduced from the original size (5Dii won’t shoot at that low a rez). It’s been run thru photoshop, but he may do his RAW conversion and resizing there. The file name has “sum” appended to Canon’s default naming scheme, indicating that he did some combining of layers, but combining darks with your light(s) is practically required for getting astro shots without hot pixels.

I think it’s a straight reduction rather than a crop. The vignetting is symmetrical, and the coma from his lens is also symmetrical.

Can’t tell much from the noise present, between the reduction and the jpg artifacts it’s just about impossible to make any assumptions based on noise as to whether it’s a composite of lights or not. 6400ISO in the 5Dii makes for quite a bit of noise, and darks don’t reduce the noise by much.

If it’s a single shot, Perseus surely smiled upon him that night. Over a dozen in 30 seconds is very lucky indeed.

[chupathingie]

hmmm… I bought one of these recently:
http://www.amazon.com/gp/product/B00317H7Q4/ref=oss_product
Very wide fisheye, 180 FOV if you have a full-frame sensor (but you have to chew the permanently-mounted shroud off) or ~160 degrees for a .65 sensor unmodified. 360X180 panos in 3 shots on a 5DII. The focus is decent and the color correction is much better than I was expecting. Well worth $350.

Oh!
http://www.amazon.com/Rokinon-Aspherical-Fisheye-Digital-Cameras/dp/B002LTXQUE/ref=pd_cp_p_1
Same lens, same manufacturer, different branding for $266.

[chupathingie]

Love the scenery up there… I’m going to do a road trip up the alcan someday, just to see some of it first-hand. Cool pics!

[chupathingie]

Yah, very pretty… nice to see that the monsoons haven’t completely abandoned you this year.

[chupathingie]

Sweet! Where’s the party? 😉

I temped for years. Believe it or not, I really miss it.

Oh, and congrats!

[chupathingie]

hmmmm… looks like expectations are that it will not extend below 49 degrees N latitude. Leaves me out, but you might catch some, Orionid… I suspect you’re not terribly far south of that. Should be visible from Toronto supposedly, which puts the Adirondacks in range.

[chupathingie]

Not sure where else to post this, but we’ve got a CME headed our way tonight… should be a good night to set up a tripod and try for some aurora action, especially for you northern folks. I’m going to have a look myself, even as far south as I am. I’ve seen them as far south as Atlanta before, so ya never know. With my Clear Sky Clock looking like it does, I can’t miss the chance.

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