Wednesday, March 31, 2010
Conditions nixed looks like soupy bowl
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At rallys getting some food
Just to learn a few things about the little scope, which I've been neglecting, for it's much bigger brother in the Celestron product line. . . :)
I'm off and running errands now, on the way over there. Will likely be not staying out there very long, because conditions look to be pretty poor.
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Not much time to post
I know I'm working late and won't know more until later. Hope to be there by 8pm but it's more likely to be 8:30
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Tuesday, March 30, 2010
Nice evening with some clouds
Plan to open tonight at 8pm
I'm hoping to see a few members and maybe some core group, who can tell who will show up.
Last night a 9mm was too powerful for Mars conditions were not good enough.
A 15 mm was okay with the c14. A 12 or 13mm might have been the limit but I didn't try those.
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Monday, March 29, 2010
Had to turn off the heater
Mars looks awesome when the heat currents settle down.
Nice dark patches visible in 15 mm eypiece with c14 tonight.
It looks a lot like Jupiter it's so big in the eyepiece.
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Tuesday, Wednesday and Thursday
I'm going to try to be here most of the nights this week. The difficult one will be Thursday night.
You may have to stay tuned here for an update regarding Thursday night.
Pvideo@aol.com
Check out the low light iPhone photo from Monday night. Photo shows the Celestron C-14 along with my small Nexstar 4SE in the foreground. In the back you can see my observers chair which visitors can sit on sometimes to get a more comfortable view while looking through one of the telescopes.
Also,
It will be warmer later in the week.
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Sunday, March 28, 2010
Friday, March 26, 2010
A very busy week
Wasn't able to get to the observatory Wednesday or the faac general meeting on Thursday.
Greg
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Wednesday, March 24, 2010
How pigeons almost stopped the restoration project
When I talked with Dr. Timothy Dey about the restoration project he told me that there had been some fear that the droppings inside the observatory were pigeon droppings. Pigeon droppings have been known to make people sick at times. You can "google" and research pigeon droppings on the internet and find out that sometimes when a large amounts are anywhere, even in a pile next to a building they can contain viruses or other micro-organisms and this can be picked up and when people breath these they may become ill.
SMALL DIGRESSION - About waste in the ecosystem.
Of course in nature, usually remains and droppings just end up as natural fertilizer over time and are broken down by the soil worms, and other micro-organisms. Animal waste is just a normal part of life, but when it accumulates it can cause problems - especially outside the natural environmental cycle Inside an enclosed building with a cement floor, there is no natural ecosystem to clean up the droppings and create new soil.
TO CONTINUE OUR STORY
There's the possibility that a hazmat procedure would have to happen in the cleanup and that would cost a lot of money and could have be a pretty big expensive hurdle. It turned out that they were sparrow droppings and although I'm sure they were yukky (is that the proper term), it apparently was less of a threat and not as serious a need for hazmat recovery. The observatory was cleaned up and a specialist with a license checked it out anyway. Thanks to good old fashioned networking by Dr. Dey.
PALOMAR - PIGEONS, PIGEONS EVERYWHERE
Ironically one of the largest observatories in the world is the Palomar Observatory in California, which is home to the 200 inch Hubble Telescope. According to Wikipedia:
The word palomar is from the Spanish language, dating back from the time of Spanish California, and means pigeon house (in the same sense as henhouse). The name may be in reference to the large shoals of pigeons that can be seen during the spring and autumn months atop Palomar Mountain or reminiscent of an old pigeon-raising facility built there by the Spaniards.
The pigeons almost had their revenge on our small observatory, but the school and FAAC club restored it anyway.
Note last location was wrong
That's how it is with new technology I have to get back to real work now.
Greg
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Location:W Grand Blvd,Detroit,United States
Here's a screen shot from the stereo satillites
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Location:Denmark St,Detroit,United States
Screen shot of green snow under NASA 3d sun alert
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Location:Maple St,Dearborn,United States
Up and coming 3d sun review
But also I'll get alerts on any big solar events that NASA sends out from the stereo system to 3d sun users.
Here's a screen shot of new alert samples.
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Location:2nd Ave,Detroit,United States
First blog entry from iPhone
Saturday, March 20, 2010
The Problem with newsletter designs and web downloads
Here's an example of a problem that can happen at the end of a small publishing cycle. The FAAC Astronomy club has a newsletter. I've been the editor of it for a few months now, starting in January. Getting the articles together can be a challenge.
Friday, March 19, 2010
Observatory will NOT be open tonight - by me.
What's in a nickname.
Thursday, March 18, 2010
Messier Marathon, torture test or brisk walk? A deep sleep post
Okay. . . here's a update from the walking comatose, me.
Wednesday, March 17, 2010
Finally aligned the mount
Monday, March 15, 2010
High Resolution means a Higher Price
HIGH RES IS BETTER
One of the more experienced imagers in the group at the last meeting brought up the fact that if you blow up an image to zoom in and make a print, it's usually better to have more detail. To get more detail you're better off with a higher resolution sample to begin with. But this can become a case of experimenting and determining if the higher resolution is useful and helps you're images, displays, prints etc. And of course you need the digital resolution in the camera to begin with, a more expensive chip with a higher resolution. If you don't have the resolution to play with, you're not going to get a higher resolution sample (unless you use more power and overlap photos, but we aren't talking about that).
It becomes more of an experimental thing, something to play with and learn, but also taking into account what others have learned.
There are things about the human's perceive an image that allow us to fill in detail where it's missing. We have the ability to fill in details. This happens more with moving images than stills however. But we can still fill in details, so we can sometimes use this characteristic and reduce details, processing and cost without a noticable drop in quality.
In some cases things like color can be cheated on and may add to an image with other details, like chroma (or brightness in black and white) providing the details. We can see this with older television systems. With the advent of Color TV, color had to be added to a previous system. It required a "color component" to be added to the signal, but they didn't have the broadcast space to put in all the color details. It was discovered that all the details didn't need to be added and they could "cheat" a bit adding less color and the way the display systems and our eyes worked, we'd fill in the details. This saved on color space, and resolution. Allowing color to be added with a thing called "color burst".
The color burst information was actually 4 times less detailed than the black and white picture, but the average viewer never noticed this. Color burst was supplying enough color detail to give our eye an idea what colors were in the image and as the image was moving there was more room for a loss of detail without viewers noticing a resolution loss. In the same way we might be able to reduce the red, green or blue components of an astrophotograph by 4 fold and not notice the difference. The overall resolution and in the composite photograph we end up with not might look the same to our eyes. Using binning we may increase the brightness of a channel and decrease resolution, but the human eye we might not notice the difference, especially on a computer display.
In NTSC earlier Television
Actually two fields of reduced resolution were sent, called interlaced fields. These were being delivered in the old days, a slice and dice of the image which actually had slight movement between each 1/60th second field. The Television displays would mush all these signals together and the 60 interlaced field per second would merge into this 30 frames per second image on the glowing phosphors of the older television display/tube. (I'm using round numbers of 60 and 30 FPS.) This blurring would not be noticed unless you somehow digitally grabbed a still image and examined it carefully. If you took a digital still of an image, you'd see the blur artifacts. This can still happen to still captures from interlaced systems, unless they sample only one field of the 2 field image and effectively remove half the vertical resolution a still from an interlaced signal will likely have motion artifacts.
But motion was more of a issue with moving images and interlaced systems will likely not cause a problem with a still image such as one from an astrophotography. But we don't use interlaced systems much in astrophotography. Modern systems are using more of a progressive frame capture type of video grabbing technique (unless you're using an NTSC video camera.) A webcam would likely be giving you progressive images.
A DIGRESSION WITH DISCUSSION OF MOTION VIDEO vs FILM
In some countries they had a different system called PAL, which had single frames or images, like a still arriving all at once. These were more like traditional film movie houses which would display 24 frames each a full photo transmitted to a screen seperated by a moment of black in between. In movie houses and perhaps on PAL there was this black space in between the photos being delivered that gave a different "feel" to the film being viewed. More like a flip book for some viewers, a slight artistic difference in perception. Of course in big theatres having a larger resolution on the film role helped a lot as well. American TV had a different more fluid feel for motion because it was sending more signals with movement in the image. At apx. 60 frames per second you'd capture a lot more fluid motion and movement than at 24 fps in film. So sports movements as in the throw of a football would look better on a television broadcast from a motion perspective than on a filmstrip of 16mm film at 24 frames per second. But this is in regards to motion perception, and I'm getting off the subject of astronomy stills, so let's return to still photos.
REDUCING COLOR RESOLUTION INCREASING BRIGHTNESS
In the same way reduced color (or any channel of color) can be captured today's modern astrophotography cameras using a technique called BINNING. If you BIN the RGB channels you will reduce the color resolution in your photograph and get a brighter color with less time spent exposing the image. Less resolution may be in the digital portions of the file that are in color, but the end product a stacked photo with R, G, B, and chroma channels(without binning). If the Black and white resolution is higher, the eye might not notice the loss of resolution in the overall photograph. Or alternately you could bin the black and white (chroma channel) and use higher resolution ("unbinned") RGB. Reducing parts of the image may not affect what we finally perceive on the monitor screen, especially for web or digital displays. Once the channels are stacked together the eye may take the detail from one of the channels and see that detail and fill in the missing detail from other channels. Should you capture higher detail in the color channels or lumanence channels? I can't answer that question, but with some experimentation perhaps someone with the equipment could provide some samples and analyse and come up with a conclusion. The answer likely will depend in the type of image you're shooting.
If you're shooting a star cluster or something with very little color in it, you may want more resolution in the black and white components of the image. If you're shooting dust clouds in a nebula, you may want more color resolution.
Some imagers do a digital binning of the Chroma channels as well, meaning the black and white channels to brighten up those and leave the R, G and B channels as their original resolutions. This will brighten up the black and white portions of an image, but reduce it's resolution by four fold if it's a 2 by 2 bin, grouping 4 pixels into one. Depending on the sample of the image to begin with, you may not even notice a loss of detail, but gain a lot of extra light and a bunch of dust and bright light can appear in the photo. Perhaps you're camera captured so much detail to begin with a 2 by 2 bin of the black and white really provided a lot more detail and in effect a brighter exposure after the fact. More details compared to almost no details. Higher brightness via binning can always be added after the fact in image processing programs. Higher resolution (getting rid of binning) cannot be done in post.
TRADITIONAL SCANNING
In traditional imaging systems if you're doing print a higher sample resolution will often provide more in the end result, something of a higher quality. If you can sample an image with a scanner at 4x the saved image resolution, even if it's saved at a lower resolution, you will often end up with a better picture. This is a trick of the trade that publishers have learned. It likely will work i astrophotography as well. Higher resolution may be better, but it may not be as noticable unless you're doing large prints of you're images. Binning may save you time in image gathering and provide enough resolution for your online web images without anyone even noticing the loss in detail.
Higher resolution of course means more money for the camera and possibly less "binning" which could translate into longer exposures. Longer exposures could be required to get the same brightness because you aren't binning. And that means a more expensive mount or longer tracking times to get the same results. This all translates into spending more money. Higher resolution means a higher price, there is no free lunch and in the case of astrophotography, you probably will be factoring that extra expense into added costs for the mechanical mount and optics of the telescope, a darker sky site location, etc.
Sunday, March 14, 2010
Youtube and Flickr Failures in uploading video
Not much to report - working on FAAC newsletter
Friday, March 12, 2010
Astrophotography SIG meeting Thursday 3-11-2010
I started a long rambling tutorial about Stacking and astrophotography but decided to cut it short. Re-edit it and perhaps post it later.
I decided to rewrite my blog and focus more on the Astrophotography meeting and perhaps give some links and hints at internet searching. You should know that by typing any question in Google you are bound to find some interesting technical discussion and solutions about the topic. I know many technical staff contractors who use google when they get stuck so check it out.
ASTRO IMAGERS SIG MEETING
First some meetings are really stellar (pun intended) with the images and information shown. Last Thursday the SIG group was held at Rider’s hobby shop because HFCC was closed. That’s a long way from my workplace, and I arrived fashionably late. After checking out a bunch of items at Rider’s. (I had a list of perhaps six things I might buy and wanted to see, I went into their meeting room, wow what a great meeting.)
Thursday, there was so much information at the meeting and so many great photographs it can easily be intimidating for beginners. I met a couple of other beginners in Astrophotography at the meeting. Since I’m new to this Astrophotography thing, I can easily relate to how they might feel when faced with a deluge of great photos and all kinds of technical advice on imaging.
It seems like a pattern develops for beginners arriving at this SIG.
First you’ll find that you didn’t turn in your USB key to show your own photos or in my case, you didn’t even preload a USB key. So the SIG group doesn’t have you’re photos to show them at first. Then you start seeing the work that the advanced imagers are working on. By the time you’re finished seeing what they’ve done, you start thinking . . . Wow they are so much better than what I’m working on, I don’t want to waste their time. So you leave and wonder if you’ll ever have the money, talent and equipment to get anything like the results they are getting.
This is the feeling I had a first couple of times I attended. I thought “why bother these guys with the small attempts at imaging” or “why waste their time”. After all, I’m just taking some small pedestrian styled photographs through an eyepiece and not really taking “real astrophotographs”. So I might want to wait until next time. Sometimes a fellow member will encourage you to show you’re stuff. After all it’s not about showing up others, but more about showing where you are, and asking others how you might improve your techiques, make small improvements and enjoy the hobby further. Greg Ozimek mentioned to me that he liked certain shots and that I should show them to the Astro SIG. I showed them and basically was showing them as a really basic subset of astrophotography that is more like “pedestrian photography” or handheld through the eyepiece photos of the moon. Guess what happened? I wasn’t laughed out of the room, I received complements and questions and some good encouragement.
The guys in the group no matter how advanced their techniques and far along really like to see early attempts and will give you a lot of good advice and feedback. Most of the time I don’t show images it’s because I just didn’t organize them and prepare remarks or comments to let them know. Most the time, I don’t show images, not because I’m afraid to show my early stuff, but more because I’m running out of time and doing to many projects to spend time to get organized and have a USB key with some images available. It’s something I need to work on getting prepared for. (Less blogging perhaps, more organizing.)
The advice I received from other imagers and just watching and hearing what they do is a great education in how to expand my future imaging plans, or even just an education, without doing a lot of imaging.
As those who attended Thursday found out, there are more images shown at the SIG group than are in the photo section of the FAAC website. Many of these imagers may upload their photos somewhere else. Maybe their own observatory website, or on Flickr, and you won't easily see them. One fellow member told me ahead of time he didn't see very many photos on the FAAC website, and this is true. But once you start reading the posts you may find links to the locations other FAAC members are storing their photos on. You may have to hunt a little bit and dig to find the images. Perhaps looking through more posts in the FAAC Yahoo Group before finding many of them. (This of course is more specific to FAAC members.) The FAAC website is kind of like the tip of the iceberg and just a small cross section of what all the members in the FAAC club are doing.
Although I arrived late, I was able to catch the end of a demonstration of a ($45 PC based) stacking program. These programs allow you to stack and manipulate images. There was a lot of discussion and comments about different software, both software you can purchase or freeware from the net. Some of the comments were brief, of course some of the information is technical in nature and may go over the beginner’s head. I probably understood 50% of some of the comments at times and perhaps forgot another 25% after a long day. So I’m probably lucky if I can retain 25% of what is brought up at the meetings. That’s okay, I had fun anyway.
John from Riders hobby shop mentioned a new stacking and image processing software webinar that was going to happen on the net at 9PM. It was about a new product called Fisch Image Lab given by “Explorer Scientific”. I didn’t get into the Webinar until after it started (maybe arriving at 9:25PM) but this was also very informative and showed some of the advanced features being offered in today’s software. The Fisch Image Lab software had a lot of features but was on the pricey side($249). One of the features they touted and I'm sure there's a lot more was a color curve feature that was a little more advanced than Photoshops standard manipulation. It allows you to change colors or apply changes to different parts of the image based on the intensity of the image. It also allows selective sharpening, etc over part of the image rather than the entire image, which helps bring out detail in moon photographs. Watching some of the image manipulation features on the Webinar inspired me a bit. I later I tried some of the curve color control features demonstrated thatI happened to find in a low cost image manipulation tool I already have on my Macintosh (called GraphicConverter).
This improved an Astro-image I have taken a bit and gave me some more ideas. So it becomes a process of learning a little applying that knowledge and tweaking and experimenting. If you have some images to stack and play with, you can have hours of fun getting the most out of your photos. A big advantage to today's astro imaging is you can be doing something with you’re hobby when the skies are not cooperating.
CAMERA TRACKING AND IMAGE PROCESSING
The software shown in the webinar could take multiple photos from an untracked camera and rotate and stack them automatically, even as they were being shot. It was amazing. However it seemed to work better as would be the case, with a guided mount. There were some controls that seemed to be live with camera control. I wasn't sure if these were specific to a camera under direct control, or something you would also be able to do afterward with the images. I feel that it could be worked both ways but was to tired at the time to even get into those details and figured I'd find out more later. (With the price being $249 for that software, I figure I'll have a lot of time to research that product before considering a purchase.)
There are of course to different phases in getting a good photograph when imaging for astrophotography. First you gather the images. Then you try to “tweak” the photo playing with the digital images to get the best possible final image. It’s part science and part art. There’s a lot of room to try to get the best possible image, most true to life or perhaps to emphasize some scientific feature of the object you’ve captured on “digital film”.
Computers add a whole new world of possibilities to Astrophotography and it just keeps getting better. Common image processing techniques involve programs that deal with layering, image manipulation (like photoshop) and stacking software. If you’re into photography you might have an advantage. If you’re into optics it could help. If you’re into engineering or math it could help. You can bring whatever talent you have to the hobby, although I haven’t figured out how to bring singing talent to play and get better images with while belting out a tune.
The gathering of images is just the first step. I’ve even had George Korody show me an image and remark how he gathered the images and mention that a friend of his did the image manipulation. So you can work as a team and perhaps focus on one part of process as well.
As beginners we may be taking photos with cameras that are perhaps in a number of categories, Maybe unguided, handheld, fixed on a tripod aimed at the North star. Reflections of a moon off water. Maybe handheld or in front of an eyepiece. These are more “pedestrian” (my term). You can take more than one unguided photo using a simple tripod and a camera that offers long manual exposures. Using a self timer helps keep the shake of your hand out of the photo.
FAAC member Greg Ozimek mentioned to me a good way to start out with astrophotography is to just shoot some wide shots of some area of the sky, maybe Orion, the big dipper, just some frame of the sky. It can be unguided. Take several shots, and then download some free stacking software off the internet and play with the stacking software. You’ll find out if you like tweaking images and experimenting getting better results pretty quickly. With little extra expense. Then you can focus on getting more involved.
Then you can work you’re way up. At first I concentrated on photos that would be what a pedestrian at a star party might get just holding a small camera to an eyepiece. You can learn a lot off internet articles just google terms like:
CCD Astrophotography.
Stacking software.
Free stacking software.
Barn door tracker.
These search terms will turn up a wealth of information.
Astrophotographers at least in FAAC are actually very friendly and want to help you advance in your hobby. As you get deeper into the field if you’re into imaging you’ll find you may want a really good solid mount and a way to take photographs and some access to computer software.
Don’t let the steep learning curve stop you from having fun, if that’s your goal. You don’t have to spend a ton of money to get some pretty decent results. If you’re a member of FAAC and come by to the observatory sometime, we can likely show you how to get some nice shots through equipment that FAAC has access to. How inexpensive is that?
There are so many paths to imaging perhaps different approaches. You can do long exposure landscapes with the night sky and star trails. You can do some eyepiece photography through the eyepiece with a cheap camera, usually of the moon. This is better with some setups or telescopes. Usually fast telescopes with big low powered lenses are easiest for an eyepiece handheld shot.
If you’re into visual astronomy you’re goals might be different and your purchases might be different if you decide to go into Astrophotography. There are even internet sites like Global Rent A Scope that allow you to rent a $50,000 observatory and shoot shots through that with internet control. They give you free time to try it out. How inexpensive is that?
WEBCAMS FOR PLANETS
Many are using lost cost webcams hooked up to a telescope via an eyepiece adapter. Webcams shine for planetary photography. A Webcam AVI file will record thousands of frames of a planet in the telescope. Then special software will be used to automatically can the movie and select the best few hundred from thousands of frames. These frames which are higher quality will then be stacked to provide some of the best planetary photographs amateur astronomers have recently taken.
Modern Amateur photography is far better than the old days with film. You have more choices and more control over processing with computers. You don’t have to worry about learning how to develop film or wonder if your shots turned out, you can get results quicker or take your time and tweak the images without a darkroom.
And modern day CCD cameras have very low light high gathering efficiency. Enought to advance telescope making technology to keep up with the demands of imagers. They have actually helped drive better telescope design. They are 70% efficient at turning light into an image. The old film cameras were often only 2% efficient. So modern technology is 35 times more sensitive to light than film was.
PHOTOGRAPHY IS A DIFFERENT APPROACH WITH DIFFERENT EQUIPMENT
There are different cameras and things that people focus on in astrophotography that is a lot different from visual astronomers however. You may want to be aware of this. A short focal length refractor with a good mount is preferable to a large light bucket on a dobsonian mount if you’re looking to get serious into imaging. The larger telescopes are nice, but they need really heavy and expensive mounts for stability to gather the images. One shortcut that some people use, but this is above the average beginner astronomer’s budget is a system like Hyperstar for SCT telescopes. These types of systems offer wide field and very fast focal lengths for short photographs, but a large Fastar or Hyperstar system like the Celestron C-11 could cost you $5,000 for the HD CGE edition and that’s quite a bit of money. It provides F1.9 speeds which is a very short and fast focal length and bright image for quick exposures. You can take a 30 second photo and get the same results as in a 5 minute exposure with a fastar or hyperstar configuration, but with a big telescope like the C-11 you’re only shooting at 18x. Which is for wide field images. Some are attracted to these systems for big photographs of wide areas of the sky. And they save money on the expensive mount, because they can take very short exposures 30 seconds instead of 5 minutes.
If you want to shoot small objects at higher power, then you need a slower longer focal length telescope and this would mean the image would be darker and require a longer exposure. That longer exposure time translates into a better and much more expensive mount. Imagers state they spend about 70% of their budget on the mount. So a typical high cost imager spending perhaps $20,000 on a system might have $10,000 in the mount and $10,000 in the telescopes and cameras or even more. And if they were at a $10,000 price range of equipment they may have $6k in the mount and $3k in the telescope and perhaps $1000 in other items and that could include an inexpensive camera.
Serious imagers can easily spend $3,000 to $10,000 for the camera alone. But you can spend much less. You can purchase a lower end camera for astrophotography or get into low end EOS SLR type cameras in the $500 to $900 range and get some excellent results.
You can get pretty nice results with a low end EOS SLR CCD camera and a barn door tracker as well if you want wide field photographs that track the sky. A barn door tracker could costs around $25 to build.
Perhaps an even more affordable solution exists. The best solution for many FAAC members might just be to come by the observatory and bring a Canon EOS camera with you. If it’s a Canon EOS camera, I have an adapter the we can use to fit it to the telescope and we can take a few photos that you can take home and play with. If you email me I can even send you some shots I've taken if you want to just play with stacking software. Depending on the number and amount of images you can get better results with different file types. Bring a USB key to a FAAC meeting and ask me to upload some images for you, if you wish. I can get JPG or RAW images to you for some stacking fun. You won't even have to acquire the images. Why spend $10,000 when you can experience, a little bit of Astrophotography for free? If you’re a FAAC member and we have time and I’m around, as far as I can tell you’ll be able to dive in and learn about Astrophotography, without spending an arm and a leg.
Some other tips and hints for now. If you want to get involved with Astrophotography and use CCD cameras like the Canon EOS or Nikon digital cameras there is a CD called “The Beginner’s Guide to DSLR Astrophotography” by Jerry Lodriguss. If you haven't picked up a camera yet, and are wondering about which brand to purchase, a lot of astronomers are using Canon's so there appears to be more support for those, but you can use other CCD cameras. The advantage of these is you can use them for other photos and then shoot some astrophotography. Of course I'm just scratching the surface, there's a lot more to say and write about. The "Beginner's Guide" mentioned above costs $40 and is a book on CD. If you want to purchase it, you'll need to get it from a website. Just google it. He has an advanced CD as well. It really goes over a lot of information.
He even has some of the chapters free on his website, but the book has so much more information. You could likely get as much but at a different level of information as you would in 10 meetings in the SIG group just by buying this CD. It’s very affordable and focuses mostly on CCD imaging.
Thursday, March 11, 2010
Someone at the club actually reads my blog
You have to remember I'm a dreamer and like to dream about gadgets. I dream perhaps about 20, maybe 200 or even 2000 gadget dreams before trying to actually make one. I can dream and imagine a lot, and save on perspiration (old fashion Edison work ethic) by leaving them in dreamland.
This weeks dream includes thoughts about the little 8 inch mirror I bought either for a little toying around or to have the kids at the school play with. The other day, I was thinking about creating some kind of unique and super light mono-body construction Dob. Something more like a monoframe, that held a mirror box. Sort of like an open mount. Kind of like a ("telescope man") Harold's example telescope that uses a simple board.
But instead of a board it would be more like a contructed body. Perhaps one sculpted in foam at first, like a Recumbent racing bike. Then covered in Carbon fiber for strength, like the body of a Carbon Fiber low racer. Carbon fiber would give it a killer look. I'm not saying it would be some kind of James Bond combination of a telescope and bike or something like that. That of course would be going to far. Perhaps adding a wheel kit and bike chain and sprockets would be going to far. Althought it's be interesting to say, I drove my telescope to the meet. But that's for another post and a more heavy design session.
It might have a primary and secondary box attachment and it could hold a mirror box of some kind. The secondary attaches to one end with the eyepiece and finder, like modern dob designs. It would be a monotube body with the rings and mirror boxes free floating on one side of it. Of course would have to be fairly rigid. Perhaps hoops could be designed to hold a shroud, for city viewing. Without the shroud it would make a pretty killer demo piece with a completely open design, but of course in a real field it would allow a lot of dust into the telescope and on the optics.
Then my imagination starts to go a little more extreme. How about making it a dual configuration kind of thing, maybe add a place for a second mirror that would slide in or attach some how with a different secondary or spider. Maybe two secondary cage configurations that would swap in and out. One closer to the primary which would be tilted. Perhaps the primary mirror box would have two slots to fit into and one would tilt it slightly. This would create a Dobsonian with two eyepiece and secondary positions. The first position, furthest from the mirror in standard conventional Newtonian position would be a full mirror setup with a regular spider. The second position would use a mask and the mirror would be offset. The top secondary cage might even be removable for this second configuration. In either case, the second configuration would tilt the mirror and a mask would be added to the front.
FOLDED NEWT DESIGN CONFIGURATION (configuration 2)
We'd be using half the mirror or a circle allowing light in. For the 8 inch this would be a 4 inch circle perhaps. It would reflect off half the shrouded mirror and back to an offset diagnal with the second focuser which is further back. This makes the dobsonian an offset Newtonian that is masked. Why do this? It creates a light path that doesn't have a secondary or spider at all in the light path. It's a "folded Newtonian" design in the second configuration. Basically a fully corrected clear 4 inch telescope with no color issues (like refractors) and no secondary obstruction. This is the kind of design you'd want to have to use for planetary viewing. If you don't have $10,000 for an expensive APO from Takahashi, you can perhaps build a folded Newt and have some pretty nice planetary results. Hmm. A F7.5 masked 8 inch becomes a F15 4 inch in this configuration. Sounds like a pretty cool planetary focal length design.
So I'm thinking in the second variation (of course I've had more thoughts) that if I was going to get radical with some kind of carbon fiber design, why not go further and get two scopes out of one body. Of course with designing and planning any added thing may add options, but take away others. For example adding more options and features by expanding the frame of the scope and how it works, adds weight. You have advantages and disadvatages to each design idea, which is what happens in the real world. In snowmobile design for example which changes each year, some came up with the thought of reducing parts to make the sled lighter and design each part to do many functions not just one. So a successful light design would use fewer parts. Or would require more swapping of mirror cell layouts and retain only one eyepiece and secondary in either configuration. You might have one primary mirror box and two secondary cages. One with the mask and folded optics. If both were seperate the collimation of the secondaries would be rather quick and might not require much work. If you were really good in you're design you might have some kind of adjustable tilt stops with fine adjustments to setup a tilt and tune colimation of the primary to happen with a fairly simple tilt and few adjustments to go from one mode to the other, but that's asking for a lot.
If you make it some kind of massive scope with both secondaries and focusers on it and somehow have the folded one swing into the light path when in folded mode, you've added a lot of weight to the original Carbon fiber idea. Different designs have advantages and disadvantages. Some of course just use a shroud over their Newt to make things simple. That might be the quickest solution, but you may lose a little bit of primary mirror size, due to the secondary being in the way, size compared to a true folded design with a different secondary that removes the regular one or shifts it somehow. (I'm not a fan of shifting one secondary with this design, because it would likely require more secondary collimation each time you switch modes.) If you really had the big bucks and had some kind of robotic secondary adjustment using lasers and computer controls or something like that, well then that takes my simple design and put's it into really hgih priced territory.
So I'm left with possibly going back toward a simple minimalistic design of one type to make it really light and have an advantage of using it on a cheaper lighter capacity mount or put in other cool features, but then needing a more expensive and heavier mount to use it.
Of course a million other ideas can come out of this. For example the body could have the mounting bracket built in for mouting it to a telescope mount. A built in dovetail in the sculpting of the Carbon fiber monotruss would allow you to mount it without an external bracket, just mount it to the Carbon Fiber. That of course makes it less flexible but lighter.
Then of course some would argue what's the best design and most rigid. How big would the monobody have to be to keep flexture down and why not just use light carbon fiber truss poles instead.
There's a lot of different options you might have. You might even fail without the truss poles and have to add them later. If you designed the main support frame strong enough it might handle different size mirror boxes with different sized mirrors. I could build it so it could expand. Start with an 8 inch and then add a different 10, 12 or larger mirror to it later, with a bigger mirror box and different secondary cage, the same monoframe might be workable for a range of telescopes.
Then I start thinking about that 20 inch mirror again.
Of course I could just go out and spend the money on a VK1 lowrider from Velokraft Poland and ride off into the sunset instead. Before I bore you with more dream variations it's time to sign off.
http://www.jjscozzi.com/VK1.htm - link if you want to see what a Velokraft racer looks like.
Greg K
Dents in dome part 2 / Astro SIG Meeting in Ypsi today
Riders has a lot of telescope stuff, so it should be a fun visit.
Let's see my short shopping list: I'll need to pick up a cable or two, an adapter perhaps for the little Celestron I bought and maybe some other items that I can use even at the observatory, something as radical as Celestron binoviewers or something. I've even thinking about a GPS for my scope that would work with the Hector J Robinson Observatory's mount as well, but I'm not sure about that yet. You'd still have to find guide stars to realign a cold started mount apparently, the GPS may not do to much to help in convinience with the Losmandy mount.
I have a break a lull at work so I need to get this post finished.
I found an interesting and somewhat disturbing object near the observatory a few nights ago and forgot to log or mention it but will mention this to the club and Leo. It was a golf ball. Perhaps people are playing a little golf near the observatory. Maybe on the field, which is probably not allowed, but being done anyway. It's possible that someone could be even be targeting the dome with these, but I don't have evidence of this. Still there are a lot of dents in the dome, maybe it became some kind of hobby golfers target.
Should we have a procedure in the manual in the event a golf ball crashes through the corrector plate during viewing by some errant golfer? I'd say it would have to read something like, don't touch the golf ball and try to preserve the fingerprints, or something to that effect. We might have to treat it like a crime scene, because it would be a kind of accidental vandelism.
Are we going to need to develop a process of having a lookout watch the football field for golf fanatics or crackpots? Let's hope it doesn't come to that. I suppose that might be one good reason to have more people staffing the place when it's open, to have someone outside checking the surroundings for possible problems.
I'm not living in the observatory or something like that (although last week I kind of felt like it there for a while.) So I can't say what has dented the dome in the past. I put the golf ball in the trash box inside for now. Something to keep in mind.
OTHER LATE NIGHT VISITORS
Of course the property is public property and people are bound to wander in the unfenced areas. I was surprised last week when early in the morning, we are talking about 3AM or so some young man was out playing with his dog in the parking lot near the observatory. He was throwing a large rubber ball in the lot and the dog was happy to be out and playing. He saw me and I saw him. I didn't wave or welcome him or start a dialog, because we were closed and not open of course for an event or something. As I was leaving, he and the dog wandered off. Who knows when the late night golfers might be out and about?
Wednesday, March 10, 2010
3-5-10 image from Meade EOS unmodified t1i
Desaturated image taken with the Meade. Some of the adjustments show a darkening of the corners of this photograph. The regular JPEG image was much brighter and I toyed with some basic settings to come up with this image. There are better photos out there. This is just a quick attempt to see what the Meade can do with a favorite viewing target.
Tuesday, March 9, 2010
Orion Nebula through Meade some adjustment
Here's a 120 second photo at 100 ISO of the Orion Nebula and surroundings with just a little manipulation of the color saturation, no dark frames no advanced processing.
This was taken to see how the Meade refractor would show this.
Note Banding in image didn't exist in original. Will repost later.