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morphosis7

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About morphosis7

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    Boston, MA, USA
  1. Thanks for that tip - I'll give that a shot the next time I'm under clear skies (my trip to Arizona is over, so I'll back in Boston now)
  2. Wow! This is a marked improvement over what I was able to achieve. Thanks for sharing this. Seeing that an image like this is hiding in the data I've captured is really encouraging - and gives me a path forward to potentially re-process some of the images I've already captured. The other night I was able to capture about 200 more images of the nebula - bringing my total up to 324 frames, or almost 11 minutes of light time. I also tried to capture to flat images using the process that Sam described. I'm working on re-processing the total set of images now, and will keep experimenting over the next few days. Thanks for all the help in this thread, everyone!
  3. Hey everyone, thanks for the encouragement and the recommendations that I've seen so far. There's a few things that people have said that I wanted to respond to directly... Yeah, you're right. The camera is a Sony, not Canon. Silly mistake... Thanks! I'm attaching the autosave file here. I'd love to see what more skilled hands than mine can achieve with this. I've attached the original autosave at full resolution, and then a cropped version that pretty closely reflects what I posted above. Yeah - my process has been to capture the light frames in the field, and leave some time at the end to capture dark frames immediately afterwards; still in the field, nothing has touched the camera other than me adding the lens cap. Then I drop the exposure time to 1/4000 second and fire off the bias frames so all three batches come in one timeframe. I can hear the feedback that maybe the bias images aren't needed with a 2-second exposure. Is there a threshold at which the bias frames become necessary? When I use a shorter lens, I'll bump up exposure times - getting up to 15-30 seconds if I've got my wide angle lens on. By that point I'm assuming that a bias frame is more useful? Thanks for this - I'll give this a shot soon and see how it affects the outcome. Just checked - I've got the latest version, 2.10.8. Yeah, I forgot to mention this in my setup. I've got an infrared remote to trigger the exposures, which has helped speed things up quite a bit. I'd originally used the 2-second delay timer to let my finger get clear of the camera and stop moving, but that's a lot of wasted time - and even then things don't always stop moving in time. Ooh...that's a good piece of advice. I'm headed back out tonight to a place east of Phoenix, so I'll try this out and see how things go. For everyone who has shared links for sky trackers and barn doors, thanks - I'll look to see what I can put together on this front. A DIY approach is probably going to be my friend until I can piece together the money for something commercial, but it is helpful to know what my next purchase should be. Autosave.tif Autosave_crop.tif
  4. Hey everyone, I'm looking for some advice on ways to improve my results on an image like this - and to confirm some suspicions of mine - specifically around the capturing of images. My setup is: stock Canon a6000 camera body, on a tripod but no skytracker mount, in either manual or shutter-priority mode 210mm lens, manually focused at the point where the a6000 first reports "infinite" distance (so not buried all the way) The images are: 146 light images - RAW format, 2 sec exposures, f/6.3, and ISO 3200 (the JPEG version of one of these is attached) 11 dark images 10 bias images Processing is in DeepSkyStacker, with post-processing in GIMP. I took these just outside Tusayan, Arizona a few days ago - I don't remember the specific conditions from ClearDarkSky but it was at least decent. Areas for improvement: The nebula's structure is largely illegible. I _think_ this can be improved with a lower ISO speed. The background is super noisy. I suspect this comes down to post-processing, and ISO speed. The image is basically monotone, rather than color. Honestly, I'm a bit lost here. Thoughts on possible tweaks: Without a skytracker mount (is that the right term?), I don't think going to a longer exposure would help. At 210mm, the star trails show up really quickly - and I don't think there's a way to counteract them in post-processing. The ISO speed was probably too high, which left me collecting so much light that the main body of the nebula gets blown out. Maybe dropping to ISO 800 or so would help preserve the nebula's structure, and possibly even out the background. I'm not using flat images, in part because I've been unable to figure out how I should capture them. I drive out to a capture site, and need to pack the camera up to head home - but the documentation I've seen on flats is that you need the same physical setup pointed at a brightly-lit flat white surface? Do people image those in the field? Or are they meant for rigs that don't dissassemble? Am I right in thinking that focus isn't a problem I should focus on? It may not be perfect, but the fainter stars in this image seem okay. It isn't lost on me that many people here with great images are using much longer exposures than I am (60 minute exposures, or more). That would probably help as well, as ~5 minutes of light time is a pretty small exposure.
  5. I downloaded it before 4.1.1 came out, and hadn't upgraded yet. I did tonight, so will look forward to diving into it. Thanks also for the link to the tutorial - I'll watch that and see if I start to understand what's going on a bit better.
  6. Here's the other image I referenced, of the pinwheel galaxy (which is a very faint smudge here at the top of the frame). The final exposure time after compositing was 9 minutes 30 seconds, at ISO 3200 and a focal length of 50mm (this is a crop of the larger image). I'd hoped that almost 10 minutes of exposure would show more than a faint smudge, but maybe I'm just being impatient and need to capture more images.
  7. Hello everyone, I mentioned in my introductory post the other day that I'd been getting more interested in astrophotography over the course of the last year; while I'm not unhappy with what I've managed to accomplish so far, I do see a pretty big difference between what I'm capturing and what others - even people sharing their first images - are getting. With that in mind, I was wondering if I'm just doing something fundamentally wrong in terms of the workflow that I'm following? While I don't have the budget to go out and buy much new equipment, a big goal of mine in signing up here was to learn how to use what I _do_ have more effectively. tl;dr version: Canon a6000 camera, with either a 16-50 or 55-210 lens. Tripod without star tracker, a self timer, 1-10 seconds exposure at ISO 3200 (usually). Fstop picked by camera. Camera produces images in RAW+JPEG formats, but RAW images aren't loading correctly for me in DeepSkyStacker - so I end up working with JPEG (shudder). Stack images in DeepSkyStacker, using light, dark, and bias images. Post-processing of images either in DSS or GIMP, then export as PNG. Upload image to nova.astronomy.net Longer version: I'm shooting with a Canon a6000 camera, with one of three lenses. When I bought the camera initially, it came with two lenses: a 16-50mm for "normal" imaging, and a 55-210mm lens that is more of a zoom lens. I've since added a Rokinon 12mm ultra wide-angle lens, after seeing it mentioned in some articles on astrophotography. Most of the time I use either the 16-50 or 55-210, depending on the size of the thing I'm trying to image. The camera sits on a pretty standard tripod. I think I bought it at Target, if that is any indication. Sadly, I don't yet have a motorized mount to counteract the Earth rotation. That's probably my next purchase in this area. The camera has a pretty wide range of manual settings; most of the time I set the ISO setting to 3200, pick an exposure time that balances star trails and light (usually 1 - 10 seconds), and start imaging. The camera picks the F-stop I need based on my ISO and exposure time choices. I use the 2-second auto timer so that my hand isn't on the camera when the shutter opens. DeepSkyStacker is the compositing software that I've been using, and I'm usually able to get light, dark, and bias frames during a photo session. Typically I'll take a few pictures to zero in on the thing I'm trying to photograph, then take some number of light images. After that, I take maybe 10 dark images with the lens cap on, keeping all camera settings the same. After that, I crank the exposure time down to 1/4000 for the bias images. These are all taken in the field, so the temperature and whatnot are the same as for the light images. At this point I'll start the process over again with a new target. I don't have a good process for shooting flat images - but I'm open to hearing that this is something I should figure out. Once the images are all captured, I head back to my apartment and download all the images. Load the images in DeepSkyStacker, using whatever defaults the program uses, making sure to load each category of images via the right process. Then click the Register button, and let it chew for a few minutes. After the composite image is ready, I play around with light curves in DSS and try to force the background to black and see what is left. Sometimes I'll export the image and fiddle in GIMP with light curves - but each seems to basically be doing the same thing. At the end, I have a PNG format image that looks okay, certainly with more stars than I can see with my own eye. The final step is to upload the image to nova.astronomy.net for identification / verification of what I imaged. I'm attaching one of thee better images I've gotten from this workflow - the Orion nebula, from last March. I think this was around 30 seconds total exposure, in 1-second frames, with a 210mm focal length (zoomed all the way in on my biggest lens). Trying to re-create this now from those source frames, that seems about right. ____________________________ Given all of this, I'm curious what I can be doing better with what I have? Is this general workflow something that is reasonable, or do I need to re-think what I'm doing? My inclination is to keep following this process, but to look for a few areas of improvement: Be more patient, and go for more exposures. While I don't think I should go much beyond 10-second exposure times without a star tracker, I can certainly take more images. My last time out generated a 10-minute composite exposure of the Pinwheel Galaxy, but even that doesn't produce more than a smudge. Figure out what I'm doing wrong with RAW images so I can feed those into DSS, rather than JPEG images. Try to read the docs on DeepSkyStacker, to understand some of what the default settings do in case I should be changing them. Any suggestions or pointers that people can offer would be most welcome.
  8. Hello, everyone... I've been getting more interested in astrophotography over the last year or so, starting with the realization that the digital camera my wife and I bought could do longer exposure times. I wish I'd realized this in time to buy a tripod _before_ staring up at the Milky Way near the Grand Canyon, but c'est la vie I suppose. I leave just outside Boston, so the skies here are probably awful compared to many. Still, now that I've got a tripod and have found DeepSkyStacker I've been poking around and finding that all is not totally lost here. Nova.Astronomy.net has been a helpful tool as well (I'm user 9635 - not sure if URLs are allowed to be posted here or not). I'm hoping to soak up as much as I can from the discussions here, and get better at capturing images. Comparing what I see posted here, and what comes out of the process I follow, it is pretty clear that I have a lot to learn. Thanks!
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