Showing posts with label Astrophotography. Show all posts
Showing posts with label Astrophotography. Show all posts

Wednesday, December 24, 2014

Post observing report 12/23/2014

Hi all,

I thought last night was a lost night. First I forgot all of the manuals for my equipment at home, then it seemed that the telescope would not point, ever. Here is a summary of what I learned. 

Balance is crucial

The mount would not pont properly due to a wild imbalance in the declination axis, this resulted from balancing the tube with the camera attached but without the finder attached. The resulting imbalance caused the telescope to swing wildly when slewing in the declination direction. 

Need more power, Captain!

The night ended as a result of the Canon SL1 loosing power, this was after I had spent two hours charging it to make sure it was fully charged. The obvious solution is to power the Canon from the 12v SLA AGM battery which is not at all discharged even after running both the telescope and laptop from the begining of the night to when we packed it in. 

The best eyepiece is a Canon Camera

I cannot over emphasise how impressed with the Back Yard EOS software I am. I was able to get closer to good polar alignment than I ever have before using the camera to drift align the telescope. The thing is that now even if I wanted to do something with another imager, I think I would use the cannon first to align everything. 

As I have said in the past, many times, murphy's law goes double in Astronomy. At various times, the software for pointing the telescope, EQMOD, would not take input from a gamepad, or would claim to be pointing the wrong direction, these issues in and of themselves were not fatal, and that is progress. 

The final piece of good news from the night was that we were able to catch decent images of Albireo, and while there is significant coma at the edge of the field the images of the double star itself are still impressive. But the best image of the lot is one with a meteor in it:


Finally I have revamped the astrophotography page for the blog.


Monday, December 15, 2014

The interminable list of things to do.

Hi All,

Now that the semester is nearly over, I have a couple of announcements. First, I am not going to be returning to my Mathematics PhD program at ASU. For all of my friends still working toward their piled higher and deeper degree, I wish you the best of luck, and who knows I may drop by from time to time when I am tutoring on campus.

Now that that announcement is out of the way. I am currently working on a project with my little (read: younger) brother which may or may not result in more money coming my way. In any case, I am now as busy as I have ever been working on various projects.

OpenAIP is still alive and well though the code is still in rough shape, it probably still compiles though their is a lot of learning I need to do before I return too it. Unfortunately, my coding time has been hijacked by the project with my brother.

The telescope is still in boxes, for the most part I have not had time during the busy semester to use it and now that my time is clearing up the weather is not cooperating. I am still looking to get the equipment together I need to go camping, which should happen some time early next year.

I am still hoping to work on a focuser for my telescope, using my Arduino. I don't think I posted the videos from dipping my toes into Arduino programming so here they are:


Hopefully over the break I will be getting some more pieces, specifically a stepper motor, a driver and some optoisolators. If I can get that working I will post it. Also I have decided to start a Go Fund Me page because I am shameless and all of my projects seem to be out of my price range.

Thursday, August 7, 2014

The next thing

So first light was a success, I was able to get a pretty good polar alignment and take some out of focus star images to run through WinRodder. For perspective here is a 1second black and white image of a star field from first light.

The bright star at the bottom of the frame is Vega.

I know what you're asking why would you want to take an image of an out of focus star. Well WinRoddier is software which attempts to reconstruct the wavefront of light coming through the telescope optics from Vega, the result is a reconstruction of the optical aberrations, or optical imperfections, of the mirror. In short this software will tell you if your optics are good, bad or mediocre.

Unfortunately I took images in TIFF format when I needed them in FITS format, the problem is that the software I used to operate the camera saves TIFF images in RBG (Red, Blue, Green) channel format, this results in the exact same data being written into all three channels.  Which lead me to have to go through a round of extracting the color channel data and then running it through WinRoddier.

Only to find that my aberrations were huge, not necessarily because the optics that were sent to me are bad but because I forgot about the first element in my optical system, the sky itself. Air pockets of different density refract light differently, and thus as you take an image the first lenses that light pass through are these air pockets in the sky, now from the above image I was able to measure the seeing, or the ammout of distortion caused by the atmosphere, its 2.68 arcseconds, which is not aweful (>5 arcseconds) but it sure as heck isn't good. (<1.5 arcseconds) The humidity on Monday night was high which probably contributed to the seeing. So now I need an artificial star to test my optics in doors.

Finally the software that I used with my camera is both old, and poorly designed, so I have now taken to working on a piece of software to replace it. But since have always claimed I wanted to write a Open Astronomical Image Processing software solution, now is as good a time as any to start. The code can be found at GitHub (in the Warp_Core1 directory) if anyone is interested in my next steps. It currently uses Visual Studio 2013 to compile.  

Thursday, July 24, 2014

Updates

Hi all,

I feel as if I owe the world an update, I know that sounds weird since I am under no obligation to write this blog regularlly. Anyways a few things have happened since my last post (in May) my car burnt to a cinder. So now I have my expedition vehicle  a 2014 Jeep Wrangler unlimited, the good news is this will eventually serve all my purposes, including going to Death Valley and Baja, however it will not be built out until I can pay it off, which is 72 months away. Until then we will have to plan to go to more hospitable locations.

The good news is that I have not been busy which means that I am building out my capacity to do astrophotography. Behold my latest creation:

This is the F/3.9 8" newt on a Orion Atlas EQ-G mount. Sitting in my brothers bedroom. It is not fully operational yet. I have done one iteration of balancing it and I have done a quick look at the colimation along with a first pass at collimating it:

The process is slow, I have been building some cables one which will allow me to control the mount directly via a USB interface using EQMOD. The other which is a serial release cable for my Canon SL1 camera. All in all progress is moving forward and we should at this rate be on track for Alamo Lake in Fall. (fingers crossed)

Thursday, May 1, 2014

Busy

Hi Folks,

Its been awhile but mostly what I have been doing is working. If your a facebook friend you already know that I am below 300lbs. A lot has changed in these past few months, now that I have shrunk I have much more energy! This has lead to me becoming a Doer, the result is that I am currently working with a new laptop.

Now we are moving into the Plan. I am ordering a new telescope optical tube tomorrow, and updating my pinboard. The next month will be spent trying to secure the GEM for my mount. Along with birthday money I will hopefully have the telescope and mount in late June, then the fun begins.

My plan is to start in my back yard, setting up and tearing down the scope, using eyepieces to split doubles and star testing. I have found my old DSI Pro II not only works, but works in linux as well. I hope to turn it into a guide camera on my setup.

Once the mount and Telescope have been setup I am going to try and figure out how to start my camping setups, more than likely I am going to purchase a tent, after I have some of the big ticket astro imaging items done. I plan on doing a trip to Mt.Lemmon or something of the like in August, but we will have to see. In the fall though expedition one may go off.

In the mean time Stay tuned to the pinboard as Items are purchased they will go off the list.

A couple of more items, this saturday 5/04/2014 I would like to get a group together to talk about projects they are working on. I hope to make it an ongoing thing, which may become a club.

Also I have started a wiki, Exemplar Astronomiae its latin for a book of astronomy which is meant to be copied. I hope to put up tidbits of knowledge as well as some experiments people can do with telescopes from 5-42inches. Hopefully the experiments will be detailed enough that people can repeat them. There is a section for equipment as well, with instructions for various calibration and testing strategies. My hope is that others will eventually contribute but we will see.

Wednesday, March 26, 2014

Next Steps

So I am almost to the point of purchasing my laptop. My next purchase is going to be the OTA for my next telescope. Why the OTA first, because its on back order until June, so I need to order it now and get it while the getting is good. Next is the mount, followed by my camera modification. Then comes the fun part, each of the little individual components necissary to make my telescope work properly.

These range for the coma corrector to the laser collimator to reticle eyepieces to autoguiding setups. Not to mention I have to go to a wedding in August. Hopefully we are on track to do our first expedition next October, but we will have to see. I will post pics of my laptop when it comes in hopefully in a couple of weeks.

In the mean time I have created a website for the two aspects of my business, tutoring and computer repairs. It can be found at twedgec.com.

Saturday, March 15, 2014

Running Behind

So the plan is proceeding, sort of. Right now I am saving up some money but unfortunately I am not prepping to buy a scope. The first thing I need to get is a new laptop. My current beast of burden has served me well, but its been worked too hard for too long. As a result my acquisitions are behind. My initial goal was to purchase the telescope and mount first followed by some camping gear so that I would be ready for the Grand Canyon Star party, now it looks like nothing will be happening until next fall.

If you are interested in what I am planning for a new laptop its a rather funny story, I am planning on getting a bare-bones kit and building it up myself. You can get them at rjtech.com with some $10 spudgers you can make yourself a laptop, it will be pretty heavy, however I am not noticing the girth of my old laptop as much now that I am getting healthier. I am hoping to order the laptop by mid April, once that is done I will hopefully have enough by mid-May to buy my scope, which may take a few months to get here.


Wednesday, February 19, 2014

Be the Change

The plan is still on, I am attempting to ramp up my business in order to get to the point where I can purchase everything that I will need. But I am restless, the problem is that I have a need to tinker. To this end I have bought an Aurduino Uno board as a platform for building a Temperature compensating focuser. The focuser software will run under Linux Mint.

The thing that has always bothered me about Amateur astronomy is that the tools we need for our hobby cost so much. Software which should not be expensive is either hundreds or thousands of dollars. This needs to change, which is why I started OpenAIP. However this project will never get finished as long as all of the tools needed to go around it are gestating. The good news is that there are good hardware platforms on Windows and Linux, ASCOM and INDI respectively. The next step is to build the tools on top of these platforms for image processing.

GIMP should do the job of Photoshop, and to a certain extent it does.  But we have no equivalent for Maxim DL (hence OpenAIP). My personal opinion is that a version of linux dedicated to astronomy should exist. One where you can simply boot your computer up and try it or install it and make it work for you. But this is a goal far off in the future, for now I will start with my focuser and eventually get back to OpenAIP.

Look forward to tutorials for installing INDI on Linux Mint/Ubuntu.

Ed. 
Of course after I wrote this Cinnamon inexplicably crashed so hard I had to re-image the machine overnight.


Thursday, December 26, 2013

Happy Holidays

Hi All,

I hope your are having a happy holiday season. I am sick as usual, but I did get a wonderful Christmas Gift of slippers from my Mother. I am now eating solid food again and it is glorious, as I am finally getting the hang of eating with this new digestive tract. I think I will try to make some pizza soon with pita bread as a crust.

In the interim I would like to discuss the notion of hobbies. I think that one of the reasons people are so miserable is that they do not have hobbies. Notice I didn't say a hobby, I said hobbies. Hence, since I am going to get a digital SLR anyway. I am going to go ahead and learn how to take pictures and edit them in Photoshop and Lightroom. This is on top of rebuilding my electronics making capacity.

Ultimately I want you guys to stay tuned for some interesting developments in January. I hope to have a line of EQMOD cables for purchase. Along with maybe some serial bulb cables to control Canon camera's via a Serial/USB port.


Thursday, December 19, 2013

Old Astrophotography

Hi all,

Its a double update! I was able to find an old flicker account that had all of my "best" astrophotos. These are the result of a misguided attempt to get into the game. It actually starts when I am a little boy...

See, I have always loved astronomy and so when I was little my parents would get me toy telescopes that would immediately break, they would also get me Astronomy magazines. In the back of these magazines you would see full page color advertisements for telescopes, one in particular struck my fancy. It was the LX200 with Magellan II controller, the first fully computerized GOTO telescope.

Fast forward to 2005 when I have finally scraped together enough dough to buy one. I decide to get it and the new Meade DSI II Pro monochrome camera which promises that you can take images in Alt-Az mode. (This is a lie, and never ever believe anyone who claims you can take "excellent" images with a telescope in an Alt-Az configuration.) In my case I hat a brain dump and got the 10" model. The results of a few imaging sessions are now on the astrophotography page of the website. I have tried to give the particulars of each image to the best of my recollection but the last imaging session I had was in the spring of 2007. (I think...)

Wednesday, December 18, 2013

Beginnings

Hi all,

I am one month out (from surgery) as of today. The funny thing is that things have started to happen. First there was this blog, until now it was a way to keep all of you who were interested updated about my journey and plans and now it has grown to actually planning for expeditions. There are also pages for photography and astrophotography which will hopefully be coming soon.

This week I also spent some time on the weekend playing with some old equipment seeing what if anything still worked. It turns out quite a bit. The interesting thing is that I now have the beginnings of some gear, an old set of Pössil eyepieces (the entire Meade 4000 series) which seem to be in mint condition. On top of that my Meade DSI Pro II mono seems to work, in Windows 8! I was also able to find a working GPS receiver with a USB output.

So it looks like I am on my way with my next imaging setup, but I have learned that the main OTA that I want is going to go up in price as of next year, and so I am wondering if with these next couple of Paychecks I should purchase it. That would be the start of my imaging setup however the danger in that is that I would end up with something that I could not easily test until I have a mound to go look at (and take pictures of?) unfocused stars.

Things will be getting interesting over the next few weeks folks. If you know anyone with $85 an hour who needs computer help let me know. I am also tutoring for $35 if you know anyone who needs it.

P.S. Something that will definitely be happening with my next couple of paychecks will be me fabing a cable for EQMOD.

Sunday, November 10, 2013

Order of Operations

Hi all,

Now that I am a week into my liquid diet, I think its time to admit that this is happening. If you want tips for surviving a liquid diet I would be more than happy to help. However, its time to talk about The plan again. So the goal is to be able to go to the Grand Canyon Star Party as our first expedition this will happen next summer assuming all goes well. However I need a road map for my acquisitions. Things have been made more complicated by my insistence on a Losmadny G11 for my mount.

It suffices to say that the first purchases need to be the laptop and the telescope, these will be the biggest expenses next to the purchase of a new SUV at some point in the next year, probably next fall. But we can break it down even further, the main problem with building a telescope from scratch is that you will inevitably mess things up. You can have all the wishlists and planning that you want but your going to inevitably meet with the fact that Murphy's law goes double in Astronomy.

Your main enemy is the complexity of open loop tracking systems. Everyone solves this with a guide camera, however there is something much more insidious. I have often said I will never buy a used telescope mount and here is why,


This is as close to a precision mechanical instrument as you can get in our hobby, it requires knowledge of mechanical and electrical repair and it is very sensitive to the weight that you put on it. There is no way you can just flip a switch and let it do its work. It has to be coaxed and finessed into doing its job. You cannot loose patients with it, you cannot try to reason with it. You can only be patient and work with it. If you try to take it out of the box put weight on it and get it to track and point, you are probably going to destroy it. 

This is the problem with mounts, they are a lot like cars, and this leads people to treat them like cars. That is to say that for the most part people treat there cars like shit. They assume that its going to work and when it does not they get frustrated and/or irate, when a car is a mechanical object and hence it must be maintained and taken care of, it does not need near the coaxing as an astronomical mount but the point is that you should not just abuse it and then expect me to purchase it. 

So I am going to buy the mount first, take my time assembling it, powering it on learning to balances it, getting to know its nooks and crannies and when I am done I will buy a telescope and put it on the mount, but not before I have taken the time to understand this object. After the mount then I will probably by a Camera, then the telescope and guide scope package. The laptop will also go in there somewhere since it is just a very useful object to have around. And once that is all acquired there will be test runs in my back yard then maybe in Tucson. The reason not to just get into my truck with a new scope and take it to a dark site is simple, it won't work. The scope won't work, the trip will probably be a disaster. 


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:


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. 


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?

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?

Wednesday, August 14, 2013

Some of the Nitty Gritty of Expeditions (With first scope advice!)

Hi all, Its been awhile. Sorry I  haven't posted, but its hard to think of pithy things to say when your on your back in a CT scanner. Anyway I have had substantial interest in the Astrophotography Expeditions so I think its a good time to talk about some details. (Subject to change since the first expedition is over a year away.)

 The idea is that as long as your willing to bring your own food and gear for you and yours you are welcome. We should have multiple vehicles since I can only carry one person other than myself. The idea is that there will be multiple tents, mine will be for gear and maybe 2-3 people other than myself. We will get together before hand to make sure there is tent space for everyone. Individuals will be responsible for there own sleeping bags and pillows. Now since there will be astrophotography it is going to be natural to ask the question of what other are supposed to do at night.

 I would encourage people who are bringing there own vehicle to bring a scope. This leads me to a question I get asked a lot, which is basically what kind of telescope should I buy. Since we will be under dark skies it will be an opportune time to explore the night sky. The scope I think everyone should start of with is a Dobsonian. My personal recommendation is to go to Orion Telescopes and Binoculars for your first dob. I started out on a 6" and had a blast under suburban skies, so it I would say a 6" Dob would be the low end. Now if your willing to save a bit of money I would actually recommend the XX12i Truss tube, as it will be easy to transport and give you better views at the eyepiece. The computer will give you instant gratification, by pointing you at objects and giving you tours of the night sky, but to push yourself  and get better at astronomy you need to try star hopping to your target. Finally if push comes to shove a good pair of 7x50 binoculars can give you great views without the hassle or the expense of a scope.

If you have some experience with using a telescope and your poison is taking photos of the stars and planets, well I don't really know what to tell you since I cannot recommend my setup to anyone yet. I mean stay tuned for test reports but until I actually have the scope and camera and try it in my backyard or in a field, I cannot say for certain its the right way to go. If your a novice just starting off I would go with the Orion Sirius 80 which is sort of the standard telescope to start out with for astrophotography. As for a camera, I would start of with an unmodified Canon EOS. (t3 or t3i) This will give you a taste for astrophotography.

Now you may be saying, Aaron none of these scopes are what you would buy, and that is correct. However I am not a novice, I am a journeyman. (or at least I tell myself that) I am configuring a modular system for specific targets. When the time comes you may want to do the same, these suggestions are for people beginning there journey.

I would like to reiterate that I do not recommend people jump right into astrophotography, its hard enough when you have a vague notion of what to do, its is impossible if you do not know if you have the target you are interested in in the Field of View of your scope.

Wednesday, August 7, 2013

The elusive block 3

Hi all,

In case you were wondering what on earth was going on with my previous blog post. There was a section about a Block 3 version of my astrophotography setup. This was an insanely expensive TEC refractor paired to a super expensive Paramount MX. ( I am fighting not to use the adjective astronomical anywhere on this blog.) Instead of a redo of my mount and telescope in Block 3 I have decided to just buy an APO in Block 1. Block 3 initially disappeared  but now I have added a new upgrade, to a 35mm Starlight Express camera with narrowband and  LRBG filters. This may be years down the road so stay tuned.


Tuesday, August 6, 2013

Going Modular

I owe you all an astrophotography post. This Friday while I was waiting to be hooked up to a bunch of sensors so strangers could watch my bodily functions as I slept, I was reading a book called The New CCD Astronomy. I must admit I was terribly disappointed. The main problem with the book had to do with the fact that it was written in 2002 thus it was for an outmoded world.  Since this book has come along, we now have inexpensive mounts which can carry 40 lbs, and digital SLRs capable of astro imaging. The result is that the book was mostly useless about buying equipment.

My last post on astrophotography was a rant against what is colloquially called Aperture Fever. (Not having to do with inhaling moon dust) Many might be wondering if I am only going to tell people how not to do it. Well, here is my plan for astrophotopgraphy,

Equipment (Block 1) - The idea here is to go with a modular setup that requires a little extra planing before expeditions, so initially we will go with a 5" Apo Refractor, 80mm Guide scope, mount and Digital SLR. This setup will be both portable and sturdy, the mount being weighted about 2x what it is carrying. The goal with this setup will be to capture the nebula in and around M45.

Tech Upgrades (Block 1) - This is just enough gear to be able to take photos and reduce them once we get them back. A Macbook Air with Nebulousity for image capture in the field, then a 4k+ screen for reduction and photoshop finishing.

Equipment (Block 2) - A 180mm Maksutov-Cassegrain telescope for long focal length work, planets along with other objects. This setup will be excellent for my second favor ate deep sky object, M51.

Tech Upgrades (Block 2) - The idea here is to build a bad ass gaming/number crunching/image processing machine.

In case you didn't notice I am a huge fan of the Apollo program, Once all Block 1 purchases have been made I will move onto the Block 2 purchases.





Friday, August 2, 2013

A Rant About Aperture

There is a scourge in amateur astronomy and it is the notion that you need a big telescope. The argument goes something like this, the larger the light collecting area of your the more you can see visually, and the shorter your exposure times will need to be. This is the type of conventional wisdom that gets people into a lot of trouble.

In order to image you must compensate for the movement of the earth, the result being that you need a mount or platform to track the area of the sky that you are trying to look at or image. This leads to a problem since equatorial mounts have weight limits. The result is ridiculously large mounts and telescopes, or telescopes with equatorial platforms.

This leads to a razor I have come upon in my time as an amateur astronomer, the number of times per year you use your telescope is proportional to its moment of inertia. As evidence I present the preponderance of used telescopes on astromart that say "used a few times" or "only used once." My personal experience had to do with the purchase of an 10" LX-200 ACF  which really should not be handled by one person. While sturdy in Alt-Az mode, the telescope weighted so much that I could not bring myself to use it that often.

Indeed a large swath of telescopes I would simply not recommend for this reason. Any telescope on a fork mount is cumbersome over 9.25" it is quite nearly impossible for one person to set one up safely. 8" telescopes have been used for time and memorial but we now come to the elephant in the room, what are you using this thing for exactly?

If you are using it for visual astronomy, you will be constantly let down since almost all deep sky objects that you see on APOD or in text books have been taken with some sort of digital camera. The result is that at the eyepiece you see almost nothing or something lacking contrast and color. The end result of any attempt at satisfying visual astronomy leads to a truss tube Dobsonian over 30" in diameter. We then come to the other elephant in the room which is the fact that you cannot use such an object anywhere near your home, unless you live in the middle of nowhere.

Hence, Visual astronomy is a hard nut to crack so that you end up with a very large telescope which is as complicated to set up as an equatorial telescope and that you can only  use once or twice a year at a dark site. The other option is to go to imaging, which you can do with a modest setup, which you cannot under any circumstances use for visual astronomy save for the occasional dark sky expedition. The reason that aperture does not matter for imaging is that your interested in collecting enough photons. The way you collect the photons is usually with sub frames and a digital camera far more sensitive than your iris. So you must pick your poison, either you have a light imaging setup or a big dob you lug to dark skies, anything in between is just a waist, for anything except viewing planets of course.

The reason I am posting at 4:42am on a Friday is that I have a sleep study tomorrow, so I have decided to stay up until its time to finish that.