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Stunning. I’m a geek, and I like the first better. This is the showpiece, the first is the art.

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That’s the first reason I posted this… I was hoping it might be of use to someone with a passing familiarity with scripting.

The second reason was to show off my first useful script. Shiny! 😆

I posted linkage to the original full rez because I wanted to show what using darks does for you. Reducing hides a lot of noise, I wouldn’t dare show off a sub of this image except as a comparison. This is soooo much cleaner than the individual images. If you look toward the edges, and especially the corners, you can see a little bit of CA. But that’s not what’s causing my triangular stars out there in the weeds; that’s coma. The good news is that I’ve got pretty close to the same amount of coma all around the fringes…which means the lens and body mount are properly aligned. I’d love to see someone else’s results with the same lens and a full-frame sensor (that’s the kit lens for the 5DII… 24-105 F4L). I swear, nothing points out flaws in an optics train faster than astrophotography.

BTW, coma is a common flaw in fast systems, but can be managed if the manufacturer does it well. The 70-200 F2.8L has *much* better coma, for instance, but at better than twice the price. A 200mm prime is on my list just for the stars; cheaper and better at it’s fixed FL. It’s a sorta geek thing…

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doc, that’s gorgeous!

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^that. I was afraid to even reply to this thread (my dad’s been treated for cancer twice). I’m just wishing I wasn’t 500 miles away, since he won’t tell anyone when he’s got medical issues; he doesn’t want to worry folks. I hope things work out for the best with him (yours and mine both).

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I’ve always had good luck using Enfuse for combining bracketed exposures, and I use it for the exact reasons you said… snow and clouds are just impossible to deal with sometimes.

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Location, Location, Location.

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Shoot darks, as well. 10-15 of them at least. Averaged together, they subtract off all your hot pixels and a lot of the thermal noise. Your shots will be much, much cleaner.

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I came home from the shoot thinking I’d have some cool stuff to process. Between clouds rolling in cutting me down to a small number of subs and the temperature being up in the 80’s during the shoot I wound up with too much noise and not enough data. This looks really rough compared to the M42/horsehead shots, for instance.

However, there was a plus…in my up-all-night delirium the lights came on for me with regards to that script up there^. I’m going to write and test a cleaned-up version that I can execute from a directory containing 2 folders of raw files- darks and lights- that does all of the subtraction and stacking for me then cleans up after itself. I’ll be able to simply open a terminal window in the directory of choice and type “sh stackme” and go get lunch. Heck, I might even pick apart the startup script I’ve got that adds “open in terminal” and “resize images” to my right-click menus and add stackme to that.

re:selling the bukkit… piggyback on that thing! You’ve got a mount that tracks more than well enough for several hundred millimeters of telephoto, and is that thing hyperstar-compatible? Shooting at F2 would make all that weight worth it. Another option would be to sell it and trade the proceeds in on what I’m using (geared head/ball head/astrotrac/heavy tripod… ~$1K worth of hardware). You’d be limited to only widefield with whatever lenses you have (which is not so bad as it might sound), but you can be set up in 10 minutes and taking pictures with gear that is light enough that you could actually hike somewhere with it in a pack and still be able to carry water and food for the night without having to be an olympian.

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Needs a LOT more subs.17 is far too few.

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Grasping here: do you have in-camera noise reduction on?

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^BTW, I hope you saved your shots…

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…I know a straight-up average of a stack isn’t the way to go.

/been there…

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It even has a full level with tilt and yaw that you can bring up with a quick couple of presses of the INFO button. If you have any other usability tips that you think would carry over from the MkII, please do share.

Ooooohhhh…. that‘s a nice feature!

I have yet to customize any of the controls (even after 2 years), but I’m going to play with it some tonight if I get time… I may head out into the darkness for some more astro-porn seeing as my CSS is looking so inviting on a friday night…

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It’s okay to toe the line and cross the edge every once in a while. Trey Ratcliff steps into “mildly unrealistic” all the time, but his photos are absolutely beautiful, if not Fark legal.

/Edited to add disclaimer.

I love looking at well-done HDR, some scenes lend themselves to being somewhat surreal. I’ve just gotten to the point now where even mild tone mapping is obvious to me. So far I’ve yet to play with an algorithm that doesn’t present its results as having tone mapping applied. It’s either too much (and obvious) or so little that the benefits of the added dynamic range are overwhelmed by the lack of contrast. I used Qtpfsgui for a long while and liked 2 of the tone mapping routines, but I just can’t seem to tweak them into being realistic anymore. This is due more to my own perception being attuned to what the tone mapper is doing than a deficiency in the tone mappers themselves…once you play with something enough it becomes easily spotted when someone else is doing it. I look back on what I once thought was subtle tone mapping, and it looks anything but subtle anymore.

“FARK legal” is kind of a mish-mash… it seems like the general rule is if there’s an analog darkroom equivalent, then it’s allowed. However, curve adjustments (I may just be ignorant, but I can’t think of a film analogy) are allowed, while things like darks and flats are frowned upon (which have direct film equivalents).

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Noted. Some of these will be for print, but I’m going on the assumption that most will be e-book format.

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