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.
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