Hi all,
Writing this post has been on my todo list all week. On Monday I tried to go on an all liquid diet, the result was a disaster. Mostly it was due to the amount of insulin I injected the night before. I went from a diet with plenty of glucose to one with not much glucose at all and the result was the worst sugar crash I have ever experienced.
This was a good thing, mainly because now I know that for my liquid diet, especially the night before I start, I need to adjust my insulin intake. I am going to see my doctor next week and talk to him about how I should proceed. While it was not fun I needed to try it once before I started just to get all of the kinks out of it. I found the liquid part of it to be miserable, mainly due to the fact that I wanted food so badly, but I think I would have made it were it not for the insulin issue.
I guess the main thing is that this is why we do experiments, even with ourselves as guinea pigs, it is to gain experience we can use later when the time comes.
As an update my paperwork was submitted to insurance last Friday, so I should know in the next week or so if I am approved for surgery, after that is a surgery date. I know this is two posts in a row about my health, but well that's just how it turned out. Next post will be about me trying to change my oil for the first time or my unending quest for a decent cross platform IDE. (Integrated Development Environment)
Thursday, September 19, 2013
Friday, September 13, 2013
When is a clearance not a clearance?
Hi all,
As my last update on the surgery stated I have obtained all of the clearances to go into surgery, my paperwork will be submitted to the insurance company on Monday. (hopefully) Between my announcement that I was cleared for surgery and my current post, is that while I had been told I had the clearance, there was not a formal written clearance from my psychologist. The result being me waiting around for nearly a week while we tried to get it.
This has happened before, and its the reason I could not be a doctor. The problem I would have with being a doctor is that I have a general understanding that what I do affects other people. This makes me a better person in the long run because it means I try to be deferential to them. However, the issue with a doctor is that you have a lot of work to do, and if you were to consider other peoples point of view it would make your job impossible. Why? because from your patients perspective everything you do is massively important.
The problem I have had is waiting on doctors, the worst of which was my CPAP. I had an acute illness and there was a common treatment for it. However, I could not be treated immediately due to the vagaries of our health care system. First the doctor needed to complete his notes so that the order could be placed to the durable medical equipment company, so that my insurance would pay for some of the cost of the machine. The problem came when the Doctor did not finish his notes until 3 work days after he gave me my diagnosis.
To him this was a small thing, to me it was everything. One of the worst feelings in the world is knowing your ill and not being able to do anything about it. It was no sweat of his back, and he probably had a ton of work. But there was a bit of torture that resulted. This was to a lesser degree with my Psych clearance. Its still painful though, to be trying very hard to remake yourself only to be held up by a few key strokes and the stroke of a pin by someone else.
As my last update on the surgery stated I have obtained all of the clearances to go into surgery, my paperwork will be submitted to the insurance company on Monday. (hopefully) Between my announcement that I was cleared for surgery and my current post, is that while I had been told I had the clearance, there was not a formal written clearance from my psychologist. The result being me waiting around for nearly a week while we tried to get it.
This has happened before, and its the reason I could not be a doctor. The problem I would have with being a doctor is that I have a general understanding that what I do affects other people. This makes me a better person in the long run because it means I try to be deferential to them. However, the issue with a doctor is that you have a lot of work to do, and if you were to consider other peoples point of view it would make your job impossible. Why? because from your patients perspective everything you do is massively important.
The problem I have had is waiting on doctors, the worst of which was my CPAP. I had an acute illness and there was a common treatment for it. However, I could not be treated immediately due to the vagaries of our health care system. First the doctor needed to complete his notes so that the order could be placed to the durable medical equipment company, so that my insurance would pay for some of the cost of the machine. The problem came when the Doctor did not finish his notes until 3 work days after he gave me my diagnosis.
To him this was a small thing, to me it was everything. One of the worst feelings in the world is knowing your ill and not being able to do anything about it. It was no sweat of his back, and he probably had a ton of work. But there was a bit of torture that resulted. This was to a lesser degree with my Psych clearance. Its still painful though, to be trying very hard to remake yourself only to be held up by a few key strokes and the stroke of a pin by someone else.
Monday, September 9, 2013
FFTW for fun (and maybe profit)
Hi all,
As many of you may know, for many years I have wanted to create an open source image processing suite. The core of which is a modular image processing engine. The problem with this is of course that I usually start work on it a week before the semester then all development time is swallowed whole. The first kernel of any image processing engine is the ability to identify a star on the image plane, a process known as centroiding. In order to centroid you need something like a Fourier Transform of the image (in order to compute the point spread function of the star), I say something like because there is too much noise associated with the Fourier Transform to help with very faint objects. So my first baby step was to be able to take an image from disk and get its Fourier Transform.
To do this I needed FFTW, and cfitsio. Oddly cfitsio does not compile well for 64-bit windows so a year or so ago I spent a whole night fucking around getting it to compile in VS 2010. (If you are interested in that source code it is in my git hub.) Once that was done it was a matter of figuring out how to do a real to real 2D Fourier transform using FFTW. So here we are, the image is a few seconds of noise buildup taken from my Meade DSI II:
As many of you may know, for many years I have wanted to create an open source image processing suite. The core of which is a modular image processing engine. The problem with this is of course that I usually start work on it a week before the semester then all development time is swallowed whole. The first kernel of any image processing engine is the ability to identify a star on the image plane, a process known as centroiding. In order to centroid you need something like a Fourier Transform of the image (in order to compute the point spread function of the star), I say something like because there is too much noise associated with the Fourier Transform to help with very faint objects. So my first baby step was to be able to take an image from disk and get its Fourier Transform.
To do this I needed FFTW, and cfitsio. Oddly cfitsio does not compile well for 64-bit windows so a year or so ago I spent a whole night fucking around getting it to compile in VS 2010. (If you are interested in that source code it is in my git hub.) Once that was done it was a matter of figuring out how to do a real to real 2D Fourier transform using FFTW. So here we are, the image is a few seconds of noise buildup taken from my Meade DSI II:
And now its Fourier Transform:
Most students usually do this in Matlab before trying it in C++, I guess I just like to learn things the hard way.
Friday, September 6, 2013
CLEARED!
Hello all,
This is a quick update, I have received all the clearances I need for surgery, psychological, cardiac, pulmonary. Now we submit to insurance and I may be able to get a surgery date in the next couple of weeks!
This is a quick update, I have received all the clearances I need for surgery, psychological, cardiac, pulmonary. Now we submit to insurance and I may be able to get a surgery date in the next couple of weeks!
Wednesday, September 4, 2013
The Software Problem.
A few posts ago I stated my intention to purchase a MacBook air. The good news is that the first facets of "The Plan" are months away from being implemented hence the plan is still in flux. The MacBook is probably the nicest single piece of hardware currently available, however MacOS X is not suitable for amateur astronomy in my opinion. Several Apple fanboi's heads just exploded, but hear me out. When you have a hammer everything looks like a nail.
The problem is that the primary purpose of my next laptop will be the control of the telescope and focuser for acquisition of images. While there are plenty of applications that work with OSX which will do data acquisition there are serious gaps in the hardware support. The drivers for these objects simply do not exist for OSX.
Now the gap between OSX and Windows is nothing compared to the gap between OSX and Linux. People simply do not make decent acquisition programs for Linux. Now the thing about the hammer and nail is that since OSX is a UNIX you might just say, "Aaron your a competent programmer, why don't you just write the drivers." To which my answer would be "F$#@ YOU!" because writing drivers for hardware you don't manufacture yourself is about the most arduous task one can set oneself.
The root of the problem is the fact that this hobby is small and populated mainly by a generation of people for whom modern digital technology didn't exist. The result is that most of them are windows users as a result of some anti-competitive shenanigans in the 90's. Hence everyone who makes hardware to interface instruments to computers makes drivers for windows. I would argue that any off the shelf components are best plugged into a windows computer, since Murphy's Law goes double for Astronomy.
The solution of course is to make interfaces to mobile devices, tablets and the like for controlling instruments at the observing site, Bluetooth is more than capable of wirelessly controlling a telescope. However unless wireless USB matures and becomes a standard we would be stuck with Wi-Fi for carying image data. This is a problem I am interested in working on since wires and darkness tend to be a witches brew for ruining expensive equipment. Any thoughts readers?
The problem is that the primary purpose of my next laptop will be the control of the telescope and focuser for acquisition of images. While there are plenty of applications that work with OSX which will do data acquisition there are serious gaps in the hardware support. The drivers for these objects simply do not exist for OSX.
Now the gap between OSX and Windows is nothing compared to the gap between OSX and Linux. People simply do not make decent acquisition programs for Linux. Now the thing about the hammer and nail is that since OSX is a UNIX you might just say, "Aaron your a competent programmer, why don't you just write the drivers." To which my answer would be "F$#@ YOU!" because writing drivers for hardware you don't manufacture yourself is about the most arduous task one can set oneself.
The root of the problem is the fact that this hobby is small and populated mainly by a generation of people for whom modern digital technology didn't exist. The result is that most of them are windows users as a result of some anti-competitive shenanigans in the 90's. Hence everyone who makes hardware to interface instruments to computers makes drivers for windows. I would argue that any off the shelf components are best plugged into a windows computer, since Murphy's Law goes double for Astronomy.
The solution of course is to make interfaces to mobile devices, tablets and the like for controlling instruments at the observing site, Bluetooth is more than capable of wirelessly controlling a telescope. However unless wireless USB matures and becomes a standard we would be stuck with Wi-Fi for carying image data. This is a problem I am interested in working on since wires and darkness tend to be a witches brew for ruining expensive equipment. Any thoughts readers?
Thursday, August 29, 2013
More on First Scopes
Hi all I have been thinking about first scopes for the past couple of days. I have put together this pin-board to refer people too in the future. The problem with first scopes is complicated so I think it would be best to put all of my thoughts down on paper. (so to speak)
It is a cliche at this point to point out that there are a bunch of really bad options for your first scope, but these generally fall into the category of a small refractor (50-90mm in aperture), it could be on an equatorial mount or not, it could also have a clock drive. None of the bells and whistles matter, whatever you do do not buy an instrument for visual use that is in this aperture range. The problem has to do with the fact that while they are light and portable you cannot see anything with them. Usually they have terrible quality optics but mostly the problem is that the sky will swamp out anything other than the brightest of objects in the city.
Now your going to ask me why I don't have any Catadioptric Telescopes on this list, the reason is that there focal lengths are so long, but mostly it has to do with the way they are mounted. No initiate amateur should ever deal with an equatorial mount, the set up is too complicated resulting in whole nights wasted trying to make things work. The only other option is a fork mount and there we have a whole other set of problems. Since forks grow with the aperture of the telescope you are restricted to single arm fork mounted telescopes 8" in size if you are going to use it more than once or twice. This is a hard truth to understand but the fork is both heavy and weirdly shaped resulting in it being uncomfortable to carry. This means that you won't use your telescope. Don't believe me? Go to ebay (or Astromart) and search for the phrase "only used once" or "only used once or twice" when looking for a telescope.
While we are on the subject, you may think that you will get a deal buying second hand telescope. This is a terrible idea for the following reason, you don't know who owned it. Telescopes are sensitive instruments meaning that if they are misused or mishandled in any way they may require costly repairs or be utterly unusable. For the most part GOTO scopes will have issues with there motors and gears, Newtonian telescopes will require collimation. These are issues you do not want to have to deal with without a stout warranty and some guidance.
The truth is that the only way your going to get into the hobby and staying in it is to have a telescope that performs well visually while at the same time being portable enough to take into your back yard at night. This leads us to the Dobsonian telescope. Basically you take a Newtonian telescope put some castors on the sides of it and put it on a rotating platform and you have an altitude-azimuth telescope. Add optical encoders to each axis and a computer and you have something that can be used to tour the sky with relative ease.
For the impatient this is the best option in less than an hour you will have your telescope setup and be exploring the sky with 6" or 8" of clear aperture. You won't track objects but you will be able to find them. If your a patient person then I would suggest something without the computer, since it will enable you to learn the sky the hard way, finding objects by star hopping.
I would not recommend GOTO telescopes for your first scope. Why? Because they are pieces of technology, slightly anachronistic since they have a digital computer, only in the most rudimentary sense. Usually GOTO telescopes end up being unusable, leading to a great deal of frustration with no objects being viewed through the scope.
Now the last and most important tip is this, Amateur Astronomy is a frustrating hobby no matter how you do it. There are very few shortcuts that don't end up being headaches at some point. The point I am trying to make is that perseverance is a necessary and sufficient condition no matter which road you chose to make astronomy your hobby.
It is a cliche at this point to point out that there are a bunch of really bad options for your first scope, but these generally fall into the category of a small refractor (50-90mm in aperture), it could be on an equatorial mount or not, it could also have a clock drive. None of the bells and whistles matter, whatever you do do not buy an instrument for visual use that is in this aperture range. The problem has to do with the fact that while they are light and portable you cannot see anything with them. Usually they have terrible quality optics but mostly the problem is that the sky will swamp out anything other than the brightest of objects in the city.
Now your going to ask me why I don't have any Catadioptric Telescopes on this list, the reason is that there focal lengths are so long, but mostly it has to do with the way they are mounted. No initiate amateur should ever deal with an equatorial mount, the set up is too complicated resulting in whole nights wasted trying to make things work. The only other option is a fork mount and there we have a whole other set of problems. Since forks grow with the aperture of the telescope you are restricted to single arm fork mounted telescopes 8" in size if you are going to use it more than once or twice. This is a hard truth to understand but the fork is both heavy and weirdly shaped resulting in it being uncomfortable to carry. This means that you won't use your telescope. Don't believe me? Go to ebay (or Astromart) and search for the phrase "only used once" or "only used once or twice" when looking for a telescope.
While we are on the subject, you may think that you will get a deal buying second hand telescope. This is a terrible idea for the following reason, you don't know who owned it. Telescopes are sensitive instruments meaning that if they are misused or mishandled in any way they may require costly repairs or be utterly unusable. For the most part GOTO scopes will have issues with there motors and gears, Newtonian telescopes will require collimation. These are issues you do not want to have to deal with without a stout warranty and some guidance.
The truth is that the only way your going to get into the hobby and staying in it is to have a telescope that performs well visually while at the same time being portable enough to take into your back yard at night. This leads us to the Dobsonian telescope. Basically you take a Newtonian telescope put some castors on the sides of it and put it on a rotating platform and you have an altitude-azimuth telescope. Add optical encoders to each axis and a computer and you have something that can be used to tour the sky with relative ease.
For the impatient this is the best option in less than an hour you will have your telescope setup and be exploring the sky with 6" or 8" of clear aperture. You won't track objects but you will be able to find them. If your a patient person then I would suggest something without the computer, since it will enable you to learn the sky the hard way, finding objects by star hopping.
I would not recommend GOTO telescopes for your first scope. Why? Because they are pieces of technology, slightly anachronistic since they have a digital computer, only in the most rudimentary sense. Usually GOTO telescopes end up being unusable, leading to a great deal of frustration with no objects being viewed through the scope.
Now the last and most important tip is this, Amateur Astronomy is a frustrating hobby no matter how you do it. There are very few shortcuts that don't end up being headaches at some point. The point I am trying to make is that perseverance is a necessary and sufficient condition no matter which road you chose to make astronomy your hobby.
Monday, August 26, 2013
Signal and noise
Hi all, I owe you a blog post but I have actually been busy. The surgery stuff is progressing I still don't have a surgery date and I am still massively frustrated with the disaster we call an insurance industry in this country. However I am not going to complain about that I am instead going to complain about something else.
When you don't have a telescope for astrophotography you spend most of your time researching which telescope to buy. Such things occur naturally with hobbies, since the goal is to chase the dragon for the most part. Its strange the first money out the door is going to be spent on a car, an old Subaru Legacy 5 speed (hopefully) then comes the telescope, then comes the software for the telescope then comes the computer upgrades.
My point is that planning is the only thing I can do and part of planing is research. The problem with research is that because the community is small there is a lot of superstition being perpetrated as fact. The best example of this I have come across is focusing. Astrophotography is part art part science. The art is in the photographs, the science is in the planning on how to get to the photographs. When it comes to actually taking picture I anticipate trouble in two actions, the first is in polar aligning the mount, this must be done any time you move the telescope to a new location or break it down and set it up. The problem with polar alignment is that it is complicated and you want to do it well, this may mean taking a couple of hours to polar align your mount. The methods for polar alignment are not all that controversial.
However the second place I think I will have issues (and by I, I mean all astrophotographers) is focusing the telescope and keeping it focused. There is a great deal of information about focusing some of it might not be all that useful. The problem comes in that for the most part telescopes bend light so it comes to a focus, how they do this is very much dependent on the length that the light has to travel. The problem is that focusing needs to be exact, the goal is to get stars as small as possible on the imaging medium. You can do this crudely by hand, but most go to some sort of mechanical help for this, then there is the problem on thermal expansion. See most objects length changes with temperature, the result is that your focus (the place where your stars are smallest) moves as the temperature changes. This also means that the spacing of your lenses changes as temperature of the cell holding them does.
This could result in a lot of painful problems, not the least of which is people telling you that you should not get a carbon fiber telescope tube for a refractor since the lens cell is designed to compensate for changes due to thermal expansion. This is however a third order affect, the expense of getting a carbon fiber optical tube is a first order effect on your wallet. The interesting thing is that you should probably refocus periodically anyway because your never going to be sure where the best focus is.
Let me explain, when I was talking with my friend and mentor about this issue he asked me this question, "Where are these people going to get 0.5" seeing?" In order to see the effect of having a carbon fiber tube you would have to have really nice skies, since the is not a uniform object, its temperature and speed vary we get tiny lenses forming in the atmosphere as the local air changes, this is called seeing. Seeing acts like little lenses dancing in front of your objective, resulting in stars twinkling. More than that it is something you can measure with your camera, since even when focused the seeing smears out stars on your image plane.
Seeing effects your images much more than any choice of optical tube material. So don't worry about what your optical tube is made of unless your going to launch it into space. This has also made me leery of talk of a critical focus zone on a telescope, maybe a reader can explain why between actual thermal expansion and seeing I should worry about my focuser moving a few microns?
When you don't have a telescope for astrophotography you spend most of your time researching which telescope to buy. Such things occur naturally with hobbies, since the goal is to chase the dragon for the most part. Its strange the first money out the door is going to be spent on a car, an old Subaru Legacy 5 speed (hopefully) then comes the telescope, then comes the software for the telescope then comes the computer upgrades.
My point is that planning is the only thing I can do and part of planing is research. The problem with research is that because the community is small there is a lot of superstition being perpetrated as fact. The best example of this I have come across is focusing. Astrophotography is part art part science. The art is in the photographs, the science is in the planning on how to get to the photographs. When it comes to actually taking picture I anticipate trouble in two actions, the first is in polar aligning the mount, this must be done any time you move the telescope to a new location or break it down and set it up. The problem with polar alignment is that it is complicated and you want to do it well, this may mean taking a couple of hours to polar align your mount. The methods for polar alignment are not all that controversial.
However the second place I think I will have issues (and by I, I mean all astrophotographers) is focusing the telescope and keeping it focused. There is a great deal of information about focusing some of it might not be all that useful. The problem comes in that for the most part telescopes bend light so it comes to a focus, how they do this is very much dependent on the length that the light has to travel. The problem is that focusing needs to be exact, the goal is to get stars as small as possible on the imaging medium. You can do this crudely by hand, but most go to some sort of mechanical help for this, then there is the problem on thermal expansion. See most objects length changes with temperature, the result is that your focus (the place where your stars are smallest) moves as the temperature changes. This also means that the spacing of your lenses changes as temperature of the cell holding them does.
This could result in a lot of painful problems, not the least of which is people telling you that you should not get a carbon fiber telescope tube for a refractor since the lens cell is designed to compensate for changes due to thermal expansion. This is however a third order affect, the expense of getting a carbon fiber optical tube is a first order effect on your wallet. The interesting thing is that you should probably refocus periodically anyway because your never going to be sure where the best focus is.
Let me explain, when I was talking with my friend and mentor about this issue he asked me this question, "Where are these people going to get 0.5" seeing?" In order to see the effect of having a carbon fiber tube you would have to have really nice skies, since the is not a uniform object, its temperature and speed vary we get tiny lenses forming in the atmosphere as the local air changes, this is called seeing. Seeing acts like little lenses dancing in front of your objective, resulting in stars twinkling. More than that it is something you can measure with your camera, since even when focused the seeing smears out stars on your image plane.
Seeing effects your images much more than any choice of optical tube material. So don't worry about what your optical tube is made of unless your going to launch it into space. This has also made me leery of talk of a critical focus zone on a telescope, maybe a reader can explain why between actual thermal expansion and seeing I should worry about my focuser moving a few microns?
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