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CommanderApaul posted:http://www.universetoday.com/104103/bright-new-nova-in-delphinus-you-can-see-it-tonight-with-binoculars/ Thanks! Already invited my astro-nerd friend over and letting my 7-year-old stay up late so we can view it with his new telescope 
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Aug 15, 2013 20:20
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Thank to a failed Perseid imaging campaign, I have a before and after! Here's a crude .gif, since I need to learn how to flat-frame images.
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Aug 15, 2013 21:43
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I hope you guys can clarify something for me. I was shopping around Celestron's telescope offerings and was curious about some specifications they have listed on their website. The PowerSeeker 127EQ and the AstroMaster 114EQ are listed as having focal lengths of 1000mm. However, the PowerSeeker OTA is only 17 inches long. I emailed Celestron support for clarification and they confirmed that the mirror is 1000mm fl but the OTA is about 17 inches. How is this possible in a Newtonian? That would put the focal point about twice as long as the OTA, and the eyepiece would be trying to focus at about half the length of the focal point. Are they completely full of crap or am I missing something huge in my, admittedly inadequate, understanding of optics?
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Aug 16, 2013 02:39
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It's misleading advertising. The MIRROR is of short focal length, but the OVERALL OPTICAL SYSTEM isn't. These are what are called "Bird-Jones Newtonians." They use a short focal-ratio mirror (usually a lovely spherical mirror) with an integrated barlow lens built into the focuser drawtube that can't be removed. The barlow increases the focal length and corrects for (some) spherical aberration and coma while causing all new aberrations like chromatic aberration, not to mention they have a lot of diffraction fuzz because they need a big secondary mirror. Avoid. AstroZamboni fucked around with this message at 02:57 on Aug 16, 2013 |
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Aug 16, 2013 02:52
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AstroZamboni posted:It's misleading advertising. The MIRROR is of short focal length, but the OVERALL OPTICAL SYSTEM isn't. These are what are called "Bird-Jones Newtonians." They use a short focal-ratio mirror (usually a lovely spherical mirror) with an integrated barlow lens built into the focuser drawtube that can't be removed. The barlow increases the focal length and corrects for (some) spherical aberration and coma while causing all new aberrations like chromatic aberration, not to mention they have a lot of diffraction fuzz because they need a big secondary mirror. Righteous, I knew there was something shady going on. Thanks man.
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Aug 16, 2013 03:23
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Woodsy Owl posted:Righteous, I knew there was something shady going on. Thanks man. I've been doing this poo poo for twenty years. I know all the shady stuff out there. Owned some of it too.
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Aug 16, 2013 03:30
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Pulled out the lovely $35 Bushnells, walked out onto the light-polluted apartment courtyard and saw me a nova. Pretty sweet. Easy find with binoculars too. Basically follow the Altair-Deneb leg of the Summer Triangle up a bit until you get the four stars that make the crooked-arrow of Sagitta, and the arrow basically points right at it. There's another somewhat dimmer star to the upper-left from where I'm observing (in Deneb's direction) that may be a 5.7-Mag star for reference. Little bugger is already sub-5.0. Kindof hopeful that we'll have a Summer Square before it's over.
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Aug 16, 2013 05:52
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Eegah posted:Pulled out the lovely $35 Bushnells, walked out onto the light-polluted apartment courtyard and saw me a nova. Pretty sweet. I'm going to go check it out with my Bushnell Legends. Not bothering with a scope since the humidity here right now is 86%. I loving hate August.  Hope to see something neat, though.
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Aug 16, 2013 05:58
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I had a pretty clear night here. Spotted it naked eye. It's not too hard to find if the sky's dark enough to see the main stars in Delphinus. Hope it keeps getting brighter! I took some pictures while I was out:  Nova Delphinus 2013 08 16 by venusian-weasel, on Flickr Some helpful resources and information on the nova so far: Sky and Telescope article with finder charts Self-updating light curve from the AAVSO Binocular brightness chart from the AAVSO, should you want to contribute your own observations to the light curve. Spectral information from the Virtual Telescope Project Livestream from the Virtual Telescope Project scheduled for 20:00UT Aug 19. Venusian Weasel fucked around with this message at 19:48 on Aug 16, 2013 |
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Aug 16, 2013 09:24
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I am currently putting together a manual barn door mount, so hopefully I'll be able to test it out on this nova (although I won't be able to see poo poo from my house at this rate, not with how god drat humid and bright everything's been lately). The light curve seems to be staying pretty linear so far though, so hopefully it gets nice and bright.
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Aug 17, 2013 00:51
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Mr. Despair posted:I am currently putting together a manual barn door mount, so hopefully I'll be able to test it out on this nova (although I won't be able to see poo poo from my house at this rate, not with how god drat humid and bright everything's been lately). Yeah, we're coming up on the time of the month where the moon ruins everything. I've been thinking about building a barn door mount for a while now. Since I don't have any way to track stars, I have to keep my exposures fairly short. In turn, it seems the shorter exposures don't integrate quite as well as the longer ones. A barn door mount would certainly help out a lot.
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Aug 17, 2013 01:42
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I whipped this together this afternoon.  It's uh... pretty lovely. The pine is probably too soft, the hinge is pretty loose feeling, but hopefully it works. I found people getting good results with shittier looking ones while I was planning this at least. The biggest issue I have right now is that the t nut I put in to give it a tripod mount was pulling out of the wood from the weight, so I put a bit of gorilla glue on it and have it clamped right now. Worst case I'll redo it in oak. Also I don't have a second ballhead yet (on the way though), but I can test it in the meantime. I used this as inspiration (and for the important numbers on what bolt/turn rate to use to get good tracks): http://www.astropix.com/BGDA/SAMPLE2/SAMPLE2.HTM e. Hazy enough that the moon isn't bright, also hazy enough that i can only spot maybe 5 or 10 stars. This sucks
Dr. Despair fucked around with this message at 05:10 on Aug 17, 2013 |
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Aug 17, 2013 04:37
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Update on the tracker. Got a beefier ballhead for the tripod, upgraded the hinges to be more sturdy, added a handle to the drive screw. Still not perfect, but it's usable. Still needs some work on the drive screw, it's needs some graphite or something to make it spin easier, and something to brace it because there's some slop in the hole it goes through. Still, these are both 60 second shots with a 50mm on the OM-D. With the 15mm it would be even better.   Also, out of the 38 shots I took (all either 30 or 60 seconds long) at least 10 of them had satellites in view. So much stuff in orbit.
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Aug 25, 2013 07:28
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Had a go at taking some snaps with my phone's camera through my reflector, I really have no idea what I'm doing but I'm pretty pleased with them. 
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Aug 27, 2013 13:16
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I've been routinely amazed at what I can do with my iPhone's camera for doing afocal photography. I have an Orion Steadypix adapter for iPhone, and I use burst mode in the Camera+ app with the volume button on the headphone cord as a shutter release so my chances of catching those flickery moments of good seeing increases. Next step is to stack the shots I get in Registax. I'm going to try using my friend's C8 on AVX setup so it can track so I can get a really long burst of a few thousand frames to stack so that I can get some really clean shots. Considering typical webcam stuff is only VGA resolution for stacking, I'm hoping to get some good shots with a bigger 8mp image scale. I'm definitely looking forward to upgrading to the iPhone 5S in November. Rumors and parts leaks are saying it'll have a better camera setup with f/2.0 aperture and 12mp camera as well as processor and OS updates that will allow for up to 60fps camera burst modes. That'll make it a pretty formidable camera for doing afocal imaging and stacking.
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Aug 27, 2013 16:28
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Nova Delphinus has almost faded back to 6th magnitude. Nova Delphinus 8-27 by venusian-weasel, on Flickr Here it was last night.
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Aug 28, 2013 00:24
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AstroZamboni posted:I've been routinely amazed at what I can do with my iPhone's camera for doing afocal photography. I have an Orion Steadypix adapter for iPhone, and I use burst mode in the Camera+ app with the volume button on the headphone cord as a shutter release so my chances of catching those flickery moments of good seeing increases. People keep taking about registax and using video to then composite into an overall good image. How does this even work? Every time i try to put a nights shooting into registax i get a large black square.
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Sep 3, 2013 09:50
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Without looking at the exact procedure you're using, it would be hard to tell you what's going wrong. First, are you importing it into registax as an avi? If it starts out as mpeg like off a smartphone, you need to convert it to avi first. Also, try doing stuff at lower resolution like vga just to practice.
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Sep 3, 2013 20:34
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Hmm. I think EOS cameras spit out QuickTime movs. I was originally doing it with multiple long exposures. I'll take a 3 minute video. Convert it and try again tonight.
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Sep 4, 2013 05:15
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Yup. Take a video instead of long exposure stills. That's really what Registax was made for. When you select the file to stack, select the video and the software will automatically parse out all the frames. Then it can set alignpoints automatically. Also, I'd recommend setting it to only use the 50% clearest frames. After the stacking is done you can use the wavelet adjustment sliders to clean it up. You should wind up with a decent result.
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Sep 4, 2013 05:50
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Got a suggestion for what I should shoot? 27.4S 153E. New moon tonight /tomorrow
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Sep 4, 2013 06:15
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I'm toying with the idea of building an equatorial platform for my 10" dob. Has anyone here done something like that?
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Sep 4, 2013 06:17
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There was a thread on astronomyforum.net where some guy printed a 360 degree numbered ring that he pasted to the dob base and then attached a little cheap device to the tube that would tell you the angle of the scope and it apparently worked close to what an EQ mount would give you. I'm having trouble with that site or I'd find a link. I plan on trying it myself just for fun since it was a cheap little project. Just for aiming of course, not for photography if that's what you're going for. Chernobyl Prize fucked around with this message at 04:43 on Sep 5, 2013 |
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Sep 5, 2013 04:38
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Kommando posted:Got a suggestion for what I should shoot? Shoot Saturn. You'll want to start at dusk because it will set by 9:40pm. e: I also like to run my footage through PIPP before registax, which lets you crop your footage, convert it if you need to and sort frames by quality before stacking. More frames will generally mean better quality, but you can improve your image by eliminating poor frames too. Page Downfall fucked around with this message at 15:50 on Sep 5, 2013 |
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Sep 5, 2013 15:45
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A goon who prefers to remain anonymous for personal reasons asked me to post this on his/her behalf: Great job, anonygoon! In other news, does anybody else here read The Reflector (the quarterly publication of the Astronomical League)? In June they put out a special issue about how we need to do more to bring more young people into the hobby and why amateur astronomy community is "graying." Ever since, the letters to the editor page has been full of crotchety old fucks waving their canes in the air and blaming everything from video games to facebook to hippityhop music. It's hysterical. I felt a rant coming on while reading it. quote:Dear Editor, We'll see if they have the cojones to publish it.
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Sep 6, 2013 23:21
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Excellent letter, hope they run with it. Really, amateur astronomers should be getting young kids exposed to the wonders of space through every form of media possible. I've had an interest in astronomy since I can remember, and part of that was because I watched Star Trek and Star Wars as a little kid. Looking up into space is wonderful fertilizer for a kid's imagination, and showing them pictures and telling stories about what's up there is a good way to get them hooked on astronomy. Even though I didn't eventually become a professional astronomer, having the opportunity to learn about it as a kid made me question how and why things work the way they do. Hell, you don't even have to be a kid to get hooked like that. After playing KSP a few times recently, I really got interested in the hows and whys of spaceflight, and recently I've been keeping up with what's going on at the ISS. Honestly, blaming pop music and video games for the hobby's decline reeks of the moral panic. They see kids these days don't necessarily like what they like, and assume it's because current forms of media actively dissuade kids from pursuing the things the adults like. Once people start to fall into that mindset, you end up with the cycle of alienation from the target audience that you described. Ultimately, the future of amateur astronomy is going to rely on getting people interested in science, not handwringing and angrily waving fists at pop culture. EDIT: Took some pictures of Nova Delphinus a couple nights ago. Wish I had a tracking mount so I could take some deeper pictures of the field. Seems like it's starting to noticeably redden in my pictures.  Nova Delphinus, September 4 by venusian-weasel, on Flickr Venusian Weasel fucked around with this message at 08:06 on Sep 7, 2013 |
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Sep 7, 2013 03:18
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It's been ages since I've had anything to show but I picked up a secondhand QSI 583ws a couple of weeks back and had a quick play the other night. ngc7023 QSI Test by tmarkuk, on Flickr Hopefully I will have a set of LRGBC filters next week, wish I had the money for a Sony ICX694 based camera but this is a big step up for me.
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Sep 7, 2013 20:07
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Welp, my first ever feature article for S&T has been accepted and will be published sometime next year. Just signed the contracts. poo poo just got real, son.
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Sep 13, 2013 20:03
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Ive been eyeing a pair of celestron skymaster 15x70 binoculars ever since my cheap barska 10x50s were dropped and knocked out of alignment. Celestron seems to be coming out with a new line of "Cometron" binoculars which you can get at 12x70. I would prefer a lower magnification. Does any one have any experience with either of these? Can you recommended any other sub-$150 big aperture binoculars?
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Sep 15, 2013 23:35
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Astronomy Photographer of the Year 2013 http://www.telegraph.co.uk/science/picture-galleries/10317776/Astronomy-Photographer-of-the-Year-2013.html
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Sep 19, 2013 22:27
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Alternate theories into how the universe started moves away from a big bang and to a fourth dimensional supanovae idea. http://www.universetoday.com/104863/goodbye-big-bang-hello-hyper-black-hole-a-new-theory-on-universes-creation/ higher dimensional space make brain hurty.
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Sep 20, 2013 02:27
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I just started messing around with astrophotography, using a Kodak z915 that my brother had but never used and a $30 tripod from Walmart. I had a lot of fun with it. I know I have a ways to go to get to the level some of you guys are at but I'm really happy with what I managed for being the first time working camera settings and first time even doing this. Any suggestions would be great! I used 16 second exposure and 1600 ISO for them.   These were all taken on my college campus, I'll had to get out somewhere much darker sometime. At least I'm in Maine so it shouldn't be hard to find a dark place.
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Sep 30, 2013 20:00
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Jekub posted:
I never realized that Sony made CCDs for astronomy imaging. How do they stack up against other cameras like the ones from SBIG?
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Oct 1, 2013 14:41
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SBIG may only use Kodak sensors but the same Sony sensor as in my old Nikon D40 from 2006(!) has been put to excellent use in (comparatively) cheapo astrophotography cameras for a surprising number of years now, e.g. the QHY8L. SBIG, QSI and FLI are massively overpriced compared to the utility value, though. It's the high price driving demand low driving price up, etc, mechanic... Wolf on Air fucked around with this message at 17:28 on Oct 2, 2013 |
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Oct 2, 2013 17:22
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Wolf on Air posted:SBIG may only use Kodak sensors but the same Sony sensor as in my old Nikon D40 from 2006(!) has been put to excellent use in (comparatively) cheapo astrophotography cameras for a surprising number of years now, e.g. the QHY8L. That is something I always wondered about as far as SBIG went, are they worth the price or not. A few years ago when I was becoming interested in imaging, most of the pictures you would see were done with SBIG equipment. Now that I might be moving somewhere that has decent conditions for astronomy, I am starting to look at actually buying a camera.
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Oct 3, 2013 01:14
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I can say with little doubt that the build and quality of my QSI is significantly better than the QHY I was using before. Poorly put together in China, using nasty sealant that dries out and gets dust everywhere is not ideal. It was loud, the drivers were somewhat unreliable and I never felt happy using it. The QSI on the other hand is just a joy to use, but this is a £1700 price difference so really, it should be massively better in every way. I'm mostly glad that I was able to pick up a 583ws for £1600, a bargain given the new price for one over here. It does take a significant commitment to throw that kind of money at a camera which is really only ever going to take pictures of one subject matter.
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Oct 3, 2013 19:16
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Well, I said utility value. My D40 can take nearly the same quality photos as an astronomy camera with its sensor*, not accounting for the presence of the hot mirror and Nikon's stupendously retarded non-disableable median-filtering of "raw" photos, it just needs some 3x the frames to get the same signal-to-noise ratio, which means you're going to spend 6-8x as much scope time doing it because of all the atmospheric conditions that apply. It's very much a money/time tradeoff. (My D700 is amazing.) (* perhaps also because it tends to be gently caress-cold anyway on good nights—basically all of them in the winter—here in Sweden, -15°C and below hardly rare; there's like three months in the summer that completely lack astronomical twilight by the formal definition. The sun sets, then it rises four hours later, having perigee'd 10 degrees below the horizon… here's an informative video for the people not blessed with the conditions of living around 60°N)
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Oct 4, 2013 05:14
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I looked at the QSI site and checked out the 583 (didn't see 583ws). That built in color wheel sure looks nice and the starting price is $2800.
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Oct 4, 2013 07:55
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The 'ws' designation basically means it has a 5-position 1.25" filter wheel. A 'wsg' is the filter wheel and a built in off-axis guider. There is also an 8 position filter wheel model available. If I was buying a new QSI I'd be looking at the 6-series now anyway, faster download and better cooling. The 1.25" filter wheel is a bit of a money saver, being as it's right next to the sensor it doesn't need 2" filters. If you add up the cost of an SBIG STF-8300 plus a filter wheel and the 2" filters you would need to avoid vignetting then the QSI suddenly starts to look quite reasonable (for a given value of reasonable). I had a play with a friends ICX694 chipped ATIK 460EX though and that thing is a beast, the new Sony CCDs are a big step up in terms of noise and sensitivity.
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Oct 4, 2013 11:46
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I figured that out just a bit ago when I clicked on the button to configure the camera. Looking at this and the kind of pictures it can make really makes me wish that I didn't live in Japan. There aren't many good nights in a year to use a imager like that.
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Oct 4, 2013 15:06
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