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octane2 — Centaurus A - Work in Progress
Published: 2011-04-04 14:02:12 +0000 UTC; Views: 2309; Favourites: 67; Downloads: 49
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Click here for a version on a black background.A work in progress.
I received a Feldstein #6 adapter to hook the STL-11000M directly to the FSQ-106N's focuser, thereby negating the use of adapters with thumbscrews, etc. I installed it and went to focus on a star. Star got smaller and smaller as I racked the focuser out. Eventually, I ran out of backfocus by about 1.5-2.5 cm.
The sheer frustration is indescribable. This adapter is designed to be used with this camera and scope; you'd be forgiven for thinking that it was all supposed to work without any fiddling. Well, as it turns out, I'm now sourcing a Takahashi CA645 adapter, or two. I suspect that if I was using the CFW-8 external 8-position filter wheel, that that would provide me with enough backfocus.
Anyway, I thought, bugger it, went and installed the Extender-Q 1.6x teleconverter and thought I'd image with that. First time I've ever used it and I have to say I'm very, very happy with the results -- flat stars edge-to-edge. There is a bit of vignetting, but, nothing that a good set of flats wont fix.
Interestingly, instead of operating at f/8 (from f/5) the configuration is operating at f/7.4, which is close enough. I suspect I'd need the correct spacings (or, less spacing) to operate at f/8? Anyways, no biggie. At any rate, focusing at f/7.4 is a breeze compared to f/5 on this scope!
Here's 60 minutes worth of luminance (100% crop from centre of frame) before the clouds called an end to proceedings. Very, very minimal post-processing and no calibration yet.
I look forward to spending copious amounts of time on this in the coming weeks/months.
Note, no calibration -- no dark frames, no flat fielding. I am yet to create a 600-second master dark at -30 degrees.
This is a 100% crop from the centre of the frame.
SBIG STL-11000M, Takahashi FSQ-106N (with 1.6x Extender-Q)
530mm at f/5.3 -> 745mm at f/7.4 (the 1.6x Extender-Q doesn't yield 800mm at f/8; PinPoint LE plate solving reveals it's actually operating at 1.4x)
L: 60mins [6x600s] f/7.4 at bin 1x1 -30 degrees
Cheers for looking.
Regards,
H
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Comments: 26
Great work! I'm looking forward to see your improvements 
The reason why the adapter didn't work at first might be, because there is a realtively big error in focal lenght when manufacturing mirrors and lenses. That's probably because the companies don't want to spend extra resources to match the focal length exactly with the specs. However, I hadn't thought Takahashi wouldn't care also.
5 % less or more focal lenght (5 % is the usual margin) can mean having enough or too less backfocus. I had the same thing with my cheap Newton. 5% from 500 mm are already 2.5 cm, maybe it's a worst case scenario.
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did you take a picture of that or did you draw it because i think it is very pretty
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Hmm, this may be a stupid question, but seeing as how I'm not an astronomer, I hope it's not TOO bad of a question. What is that cloud-like band in front of the star in your picture, is it clouds in our atmosphere, or is it something around the star itself?
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Dear. That's not a star. It's a galaxy. What you're seeing is the band of dust around it. [link]
This is basically what you're looking at.
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Oh! Well that would explain a few things, how big is that galaxy in relation to our own? Is it in another cluster of galaxies, or it one of those solitary galaxies outside of clusters?
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I'm not sure how big it is in relation to our own galaxy. It's a rather far blighter though, roughly 10 or so million light years away from us. That means, it's so far away from us that it takes around 10 million years to reach us. So in fact, when looking at objects in our night sky, we are in effect looking into the past.
Centaurus A is part of a group of galaxies or more part of one of two subgroups within the Centaurus A/M83 group. This group is fairly nearby,(by astrological terms) with M83 being the Pinwheel galaxy, its neighbour though they do not move relative to one another.
Is there anything else you'd like to know sweets? ^^
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Umm, being a nerd and a firm play of the old PC game of Sid Meier's Alpha Centauri, how far away is the Alpha Centauri system from us? I once heard that it was the closest star system to us, but that's all I remember.
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You're correct it is the closest system to us. In fact it's visible right now here in the southern hemisphere.
How far is it? Around 4.37 light years from our own sun depending on your source.
The Alpha Centauri system consists of binary stars and it's stars belong the constellation of Centaurus, (the hoof/leg part of the centaur)- directly across from it going right, is the the Southern Cross constellation and the Jewel Box neblua [link] which as you can see from these pictures is a stunning nebula.
Now my darling, what else can madam Kadamon tell you? 
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Hmm... Can't think of anything right- OH wait, I know! If we can't actually SEE black holes, then how do we know they exist? I mean, I know that we know/think that black holes exist, but how have we been able to prove it?
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The event horizon. Basically that's where the mass of dust etc. is circling the black hole. That is how we're able to identify with them. ^^ Galaxies have black holes in their centers, they are of course much larger.
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The Event Horizon... I heard somewhere that we THINK that time slows down once you reach the Event Horizon, or at least that's what it might look like. God, sometimes I think I watch Nova and the History Channel too much, but I can't help it!
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There's nothing wrong with taking an interest in science on this scale. I can't do maths at all, yet I love the subject.
So keep on watching the History Channel!
Yes, I would agree that time would slow down and that's based on Einstein's theory of relativity. Any large body of mass creates this effect called time dilation. The earth creates this, our sun, everything, but ours of course is on a very minute scale. With something as large as a black hole, the case is more extreme. If you were to be observing a black hole from a distance, everything around the Event Horizon would appear as if it had stopped moving, but in reality those objects are moving at incredible speeds. It has been proven that the faster you move, the slower you move through time. That doesn't mean to say your watch will tick slower, we are talking about the flow of relative time.
The real brain destroying thinking comes when we have to think about what's going on inside a Black Hole.
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"The real brain destroying thinking comes when we have to think about what's going on inside a Black Hole."
Isn't that the destruction part, where the gravity is so strong that it tears anything apart? Or in the case of a black hole, crushed everything to nothing?
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Well yes of course, but you must also remember that time and space get distorted to such an extent that even time may possibly get destroyed as well.
Wrap your head around that for a little bit. Can you imagine, time, getting destroyed? Not our clock time, but time itself.
Can you imagine everything a Black Hole swallows getting squashed into a singularity? Time, space, matter all of that, into a singularity? Okay, I just burst a vein in my head.
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Not knowing what a singularity equates to, yes. I can imagine time itself getting destroyed. That's why I find the theory of using a black hole for time travel viable, if only you could first survive the light capturing force of the black holes immense gravitational field, then survive the destruction of time itself, then have the know-how to go back and forth through time. Then again, if you COULD do all that within a black hole, you wouldn't need a black hole to go back and forth through time anyway. -shrugs- Being a sci-fi nerd, I'm used to certain story and plot-devices not making sense, so thinking of time being destroyed doesn't give ME an anurism, just makes me wonder what ELSE is out there besides black holes that we can't figure out.
Which now brings me to my next question: I've heard that some scientists believe that a wormhole is just a backside to a black hole, but I'm not sure where I heard that. Do you know anything about wormholes, and what their relationships, if any, to black holes are?
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They're two different things in the sense that a black hole would destroy you instantly, while a wormhole would just take you from point A. to point B.
Yes you'd have to distort space and time to create that kind of tunnel and by doing that you'd need mass and gravity... after that, I'm not sure.
Wormholes are just theory at this point. I haven't seen any evidence to back up their existence.
My theory on black holes however is the following: black holes are responsible for universes.
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DT,
Alpha Centauri is a triple star system. One of the stars in the system, Proxima Centauri, is the closest star to our own at 4.3 light years away.
Cheers.
Regards,
H
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Beat me to it ya little stinker. 
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Ah, thanks! I've always wanted to know how far away it is, so thanks![link]
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