Mystery company backed by James Cameron and Google executives may be an asteroid mining project | The Verge:
'via Blog this'
gfkBill adds :More here on Ars. Sounds like it's pretty doable, tow a smallish asteroid into orbit, do science and stuff.
Cool!
April 19, 2012
April 17, 2012
April 15, 2012
When the moon hits your eye like a big pizza pie, that's ridiculous
I got pissed off last night. I was sitting in my house, only a single lens to my name, and that a 2-inch beast, no mount and no DSLR. So I decided to get back to where we once belonged. 1 hour, 2 razor cuts and some swearing later i had re-created the pill mount, and was getting ready for some observing with Bill's awesome 15mm lens on loan. Batteries were charged, everything was clean and scope was ready to roll.
In short, I ended up staying awake until 5am, shooting from the beach. The Dob was beautifully easy to transport, ping the springs off, lift it out into the car, and off we went. The main attraction last night was of course, the moon. So just to make myself feel better ... I did these.
April 14, 2012
1 Star, 2 Star, Red Star, Blue Star
Both of us here at 1200mm have kids. Mine are in their mid to late teens now, while Bill's come in a little younger than that. As parents, it's natural and normal to want to pass your passions, knowledge and wisdom on to your children. Unfortunately they stop listening to you at age 11.
Enter Findlay Books with the solution .. beginner astronomy eBooks for the newest astronomers .. the strategy being "get em interested early and your work is halved!"Joy Findlay has written and self-published a series of 6 eBooks, all dealing with the things that little astronomers need to learn, shapes, colours, numbers and letters and things of that ilk. The "Rocket Boy, my First Reader" series are wonderfully presented books, utilising some of the most awesome astro-stock images to teach these beginning concepts to the smallest star gazers of them all. The colours are bright and cheerful, the pictures are fascinating and eye catching, if you're looking for something to get your daughters and sons into space, this is an awesome start!
The series doesn't attempt to make the people reading the books feel stupid either, after looking through 1200's promotional copies I had to go look up 2 of the nebulae used for myself! I personally really enjoyed this series, and it would be something I would heartily recommend to anyone with young kids.Available on Kindle Colour and anything that supports it, and at 0.99c/1.99c a download, well worth it :)
You can grab the download links here:
http://findlaybooks.com/myfirstreader/index.html
Last Year, all in one place!
Since losing the DSLR a couple of weeks ago, and missing some awesomely clear nights to boot, I have been slightly at a loss for photographic stimulus :( Once the moon crescents up a bit, I will be playing some afocal games with the IXUS however :)
In the mean time, I gathered my favorite astro shots from 2011 into a Flickr set, they have mostly been on here before, as it's a set about the blog shots, but if you wanted to go have a peek at how my shots were looking last year, feel free!
Now I just have to get Bill to do the same, although his Flickr was a barren, featureless wasteland with tumbleweeds rolling across it until recently, it now has some VERY nice stuff up there, go look!
April 12, 2012
April 11, 2012
April 7, 2012
Space is Beautiful
A View of Earth from Saturn (Photo credit: alpoma)Some pretty pretty things from space :)What Space Looks Like to Kids
Earth as Art
Hubblicious!
Apod!
Nasa Image of the Day
Space.com Best Space Photos
April 6, 2012
Tracker Update - Wobble in the Night
Later that night, I grabbed the 350D and the tracker and headed outside for some practical tests, to see if they backed up my earlier conclusions. A full moon made setup easier, rare that I'm grateful for its presence when astro-shooting!
After a few test shots to check focus (oh Live View, let me count the ways I do miss thee) I fired off seven 2-second shots of Sirius, each approx 10 seconds apart, to give me a full cycle of the motor. A quick zoomed-in review showed some disappointing drift. It was too late to get them into Photoshop, more detailed analysis was going to have to wait.
Lunchtime Easter Friday, and what better to do while eating my Hot Cross Buns than stack last nights shots and see what we had. Into Photoshop, push contrast and black levels to remove all noise, label times on the layers, and drop into a timeline in the Photoshop 6 beta. Resulting animated GIF below :
On the up side, it looks like we're tracking fairly well overall - the stars are staying put. Clearly, there are still wobble issues however, within each turn. Quite where the issues lie will be the next challenge. Is the weight of the camera affecting the motor? Seems unlikely, as the camera doesn't move. It could simply be that the motor doesn't turn smoothly over its cycle, it's heavily geared internally and might have its own issues. So next steps :
1. Test unloaded motor, see if it turns smoothly through a 360 cycle
2. Test loaded (camera attached) tracker
3. Run some longer tests, maybe motor will warm up, and also to check overall tracking accuracy for long exposures
I need to come up with a test setup that doesn't require the stars to be out! Looks like they're gone for the next few days. Perhaps a laser attached to the rig, and projected onto a distant wall? Video it climbing the wall and see if it's climbing evenly. That might be a bit slow-motion to be practical or accurate. Worth a rack though, as it sounds like fun.
Anybody got any other ideas? Anybody reading this, or am I just thinking out loud? That would be ok, it helps me work through things, but 10,000 page views would suggest we're not alone here :)
gfkBill.
After a few test shots to check focus (oh Live View, let me count the ways I do miss thee) I fired off seven 2-second shots of Sirius, each approx 10 seconds apart, to give me a full cycle of the motor. A quick zoomed-in review showed some disappointing drift. It was too late to get them into Photoshop, more detailed analysis was going to have to wait.
Lunchtime Easter Friday, and what better to do while eating my Hot Cross Buns than stack last nights shots and see what we had. Into Photoshop, push contrast and black levels to remove all noise, label times on the layers, and drop into a timeline in the Photoshop 6 beta. Resulting animated GIF below :
On the up side, it looks like we're tracking fairly well overall - the stars are staying put. Clearly, there are still wobble issues however, within each turn. Quite where the issues lie will be the next challenge. Is the weight of the camera affecting the motor? Seems unlikely, as the camera doesn't move. It could simply be that the motor doesn't turn smoothly over its cycle, it's heavily geared internally and might have its own issues. So next steps :
1. Test unloaded motor, see if it turns smoothly through a 360 cycle
2. Test loaded (camera attached) tracker
3. Run some longer tests, maybe motor will warm up, and also to check overall tracking accuracy for long exposures
I need to come up with a test setup that doesn't require the stars to be out! Looks like they're gone for the next few days. Perhaps a laser attached to the rig, and projected onto a distant wall? Video it climbing the wall and see if it's climbing evenly. That might be a bit slow-motion to be practical or accurate. Worth a rack though, as it sounds like fun.
Anybody got any other ideas? Anybody reading this, or am I just thinking out loud? That would be ok, it helps me work through things, but 10,000 page views would suggest we're not alone here :)
gfkBill.
April 5, 2012
Tracker Mini Update - Accuracy Testing
Surprisingly, and in voilation of the weather forecast, skies are clear over North Auckland on Easter Eve (is that a thing?) Which reminded me that the epoxy on my tracker cog-and-nut assembly must be set. Time to test!
Before reassembing the barn door, I decided a bit more scientific testing was in order. First I threaded the cog onto a bolt and attached it to my hand drill. Revving it up, I could get a feel for how much wobble there was as it revolved - was the nut centered on the cog now? Looked pretty good! It became clear there was a reasonable amount of play in it at right angles to rotation axis, but that wasn't too concerning as the wobble was parallel to the bolt, once assembled the other componants would mitigate this.
I was about to head outside, when a thought from earlier in the week resurfaced. Why not video the mechanism turning, and do some metrics on the resulting video to see how smoothly the thing was running? Maybe the motor itself wasn't that stable for eg? This would give me a fairly accurate sense of things without needing to touch the SLR. My cell-phone camera was drafted in, 30fps providing plenty of "resolution" time-wise.
Below is the resulting graph, generated by stepping through with quicktime and recording in a spreadsheet the elapsed frames as each tooth of the cog passed a set point. All in all, a pretty good result! The graph looks nice and linear, within the margin of error of the fairly fuzzy video I was working with. Cogs across the bottom axis, frames up the y-axis.
Time for some star tests!
Before reassembing the barn door, I decided a bit more scientific testing was in order. First I threaded the cog onto a bolt and attached it to my hand drill. Revving it up, I could get a feel for how much wobble there was as it revolved - was the nut centered on the cog now? Looked pretty good! It became clear there was a reasonable amount of play in it at right angles to rotation axis, but that wasn't too concerning as the wobble was parallel to the bolt, once assembled the other componants would mitigate this.
I was about to head outside, when a thought from earlier in the week resurfaced. Why not video the mechanism turning, and do some metrics on the resulting video to see how smoothly the thing was running? Maybe the motor itself wasn't that stable for eg? This would give me a fairly accurate sense of things without needing to touch the SLR. My cell-phone camera was drafted in, 30fps providing plenty of "resolution" time-wise.
Below is the resulting graph, generated by stepping through with quicktime and recording in a spreadsheet the elapsed frames as each tooth of the cog passed a set point. All in all, a pretty good result! The graph looks nice and linear, within the margin of error of the fairly fuzzy video I was working with. Cogs across the bottom axis, frames up the y-axis.
Time for some star tests!
April 3, 2012
April 2, 2012
April Skies
Well here we are in April already. I apologise for my lack of activity of late, lots of things happening around my life at the moment, including injuries, physiotherapy and notably, a burglary. Which, it has to be said, sucked. They got my telescope lenses and our camera.
So Bill is doing awesome work with the tracker at the moment, I wont be shooting for a while :(
Dear Canon NZ, any chance of a free 5D? Mk II will do, I'm not greedy!
In other news, the Hike to the Stars event we all planned and spent money on camping gear to organise was totally cancelled due to the worsening weather, so we're thinking October/November now, or possibly a smaller expedition will happen later, anyone whose interested should watch this space!
Anyways, on to the skies this month, as that's supposed to be the purpose of this post.
Jupiter and Venus will be visible early in the evening sky this month, after being a pair of drama queens last month. Mars is still out and about and getting dimmer and smaller as we pull away from it. Saturn, that beautiful gem, is up in the northern sky and Titan is well visible about 4 ring-diameters from the planet, an awesome site and if you want to see it, come over, and bring your own lenses because I no longer have any :(
The usual suspects are around this month, Crux, Orion, Scorpio, both Magellanic clouds (see Bill's awesome photos),
Mercury makes a good looking morning sky appearance this month, rising due east 2 hours before the sun in the middle of April, in the beginning of the month, it's "only" 95,000,000km from us!
As usual I will be updating the 1200mm Calendar with what I can find this month (Google-Fu pending of course). Speaking of Calendars, I have added some calendars to 1200mm's including: Cassini's tour of the Saturn System,
Oh and the blog got it's 10,000th page view this week! YAY!
Anyways ... keep looking up guys!
Interesting and/or Awesome things!
So Bill is doing awesome work with the tracker at the moment, I wont be shooting for a while :(
Dear Canon NZ, any chance of a free 5D? Mk II will do, I'm not greedy!
In other news, the Hike to the Stars event we all planned and spent money on camping gear to organise was totally cancelled due to the worsening weather, so we're thinking October/November now, or possibly a smaller expedition will happen later, anyone whose interested should watch this space!
Anyways, on to the skies this month, as that's supposed to be the purpose of this post.
Jupiter and Venus will be visible early in the evening sky this month, after being a pair of drama queens last month. Mars is still out and about and getting dimmer and smaller as we pull away from it. Saturn, that beautiful gem, is up in the northern sky and Titan is well visible about 4 ring-diameters from the planet, an awesome site and if you want to see it, come over, and bring your own lenses because I no longer have any :(
The usual suspects are around this month, Crux, Orion, Scorpio, both Magellanic clouds (see Bill's awesome photos),
Mercury makes a good looking morning sky appearance this month, rising due east 2 hours before the sun in the middle of April, in the beginning of the month, it's "only" 95,000,000km from us!
As usual I will be updating the 1200mm Calendar with what I can find this month (Google-Fu pending of course). Speaking of Calendars, I have added some calendars to 1200mm's including: Cassini's tour of the Saturn System,
Oh and the blog got it's 10,000th page view this week! YAY!
Anyways ... keep looking up guys!
Interesting and/or Awesome things!
April 1, 2012
Every Night I'm Stackin'
On the last night of my recent barn door testing, knowing the limitations of the barn door as it stood I knew I had a pretty good tracker. As long as I stuck to short exposures, the stars weren't going to move a whole lot - time for some stacking! Large Magellanic was catching my eye that week, a long exposure on an earlier test having shown some potential. So I set the camera to 800 ISO, 3.2" continuous shooting, and locked the remote shutter down. I shot several sequences, the best one in terms of focus being 15 frames, including a dark frame.
Cruising the intertubes for tips on stacking, DeepSkyStacker kept coming up, so I downloaded it. After downloading the current beta to get around a bug in the release version with large RAW files, we were away. It understands dark frames, and a few other things that I need to dig into, but it was by-and-large easy to use.
The Magellanic stack came up pretty good. Kinda noisy, and at some point the "cloud" went yellow, but some great details in there. I think I could get more out of the stack, especially with noise reduction and light pollution reduction, but it's been a good learning exercise. Longer exposures are apparently better, even for stacking, so I can crank that up some when the barn door is purring. Once the stars come out again, I'll be grabbing ValHallen and heading out of town to find some dark skies.
Barn Door Testing
I finally had a chance to fine tune the barn door last week. A few days with a borrowed 550D, with it's larger review screen and Live View, meant I could do some decent field testing.
First night... and some flawed methodology led me a little astray. I was shooting once a minute, for a few minutes, then checking for drift. There was a small drift, so I did some maths, figured out how far off it was, and adjusted the motor speed. No joy, still getting trails, albeit small ones. I was close, but another session with screwdriver on hand for adjustments on-the-fly and I still couldn't get it right. Ah! Maybe it's not trails, maybe it's wobble - perhaps the motor or mechanism is uneven.
Another test run, this time taking a 2s shot every 10 seconds for a minute. A minute is one cycle on the mechanism. Zoom way in on review, step through the shots, and I could see what was up - the stars would creep ahead, then drop back again. The motor or mechanism wasn't turning at a constant speed. I already knew I hadn't mounted the drive nut onto the main cog quite dead centre (it slipped in the clamp), so today I ripped it off again, and remounted. Fingers crossed that was the issue, the off-centre nut was putting pressure on the drive. Next time we see some stars, I'll get out and see how we're doing!
First night... and some flawed methodology led me a little astray. I was shooting once a minute, for a few minutes, then checking for drift. There was a small drift, so I did some maths, figured out how far off it was, and adjusted the motor speed. No joy, still getting trails, albeit small ones. I was close, but another session with screwdriver on hand for adjustments on-the-fly and I still couldn't get it right. Ah! Maybe it's not trails, maybe it's wobble - perhaps the motor or mechanism is uneven.
Another test run, this time taking a 2s shot every 10 seconds for a minute. A minute is one cycle on the mechanism. Zoom way in on review, step through the shots, and I could see what was up - the stars would creep ahead, then drop back again. The motor or mechanism wasn't turning at a constant speed. I already knew I hadn't mounted the drive nut onto the main cog quite dead centre (it slipped in the clamp), so today I ripped it off again, and remounted. Fingers crossed that was the issue, the off-centre nut was putting pressure on the drive. Next time we see some stars, I'll get out and see how we're doing!
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