Common Mistakes:
I have been an amateur astronomer for many many years but I have been seriously imaging for only a little over a year. In that time I've made a "few" mistakes and I've avoided a few. Here are some I see repeated over and over, especially by beginners (although even experienced imagers repeat some of these).
Lack of Clear Goals:
I understand their are many different personality types and some of them despise lists, calendars, goals, and organization in general. And I'm not saying you need to sit down and commit your goals to writing, along with target dates, stretch goals, and all that kind of mumbo jumbo. If you are into that, great. Do it. If you're not, that is OK. But some goals are necessary.
Before you ignore me, at least hear what I am trying to say.
The very fact you want to be an imager is already a goal. It is something you simply want to be able to do. What kind of imaging do you want to do? "Well, I don't know, I simply want to shoot stuff." Unfortunately, that isn't a good answer. The kinds of equipment and skills required for different types of objects can vary considerably. What is appropriate for shooting moonscapes is very different from what is needed for shooting small galaxies. What is appropriate for shooting wide field shots of nebula is very different that what is best for imaging globular clusters. Unless you are very well off and can just buy anything you want, it is important to know what you want to image and then obtain equipment that will enable that to happen.
Where you want to shoot from can/should also influence your goals. Imaging from the center of a city is very different from imaging at a pristine dark site. Lunar and Planetary photography can be done almost anywhere. Objects like faint galaxies are going to be quite difficult from the center of a city and some compromises may need to be made (like using light pollution filters even though it will effect the color).
Where you want to shoot from can also influence how portable your equipment needs to be. Do you need to be able to load it into a car? Do you need to heft it out to the back yard? Do you have an observatory where it can stay setup?
I would suggest that you figure out an answer to at least the following questions before you purchase anything:
1) What do I want to image?
2) What are the conditions where I will be imaging?
3) How portable does my equipment need to be?
4) How much am I able to spend?
Those answers will shape your goals and they interact. For example, solar system imaging can often be done for less money than deep sky.
After answering those questions, formulate at least mentally what you want to achieve. An example would be, I want to do narrow band, wide field imaging of nebula from my red zone backyard observatory.
That will now put you in a position to acquire the necessary gear and skills required. That doesn't mean you can never do anything else. You might decide later on you want to add in doing wide field imaging of galaxies with a portable rig.
I have been an amateur astronomer for many many years but I have been seriously imaging for only a little over a year. In that time I've made a "few" mistakes and I've avoided a few. Here are some I see repeated over and over, especially by beginners (although even experienced imagers repeat some of these).
Lack of Clear Goals:
I understand their are many different personality types and some of them despise lists, calendars, goals, and organization in general. And I'm not saying you need to sit down and commit your goals to writing, along with target dates, stretch goals, and all that kind of mumbo jumbo. If you are into that, great. Do it. If you're not, that is OK. But some goals are necessary.
Before you ignore me, at least hear what I am trying to say.
The very fact you want to be an imager is already a goal. It is something you simply want to be able to do. What kind of imaging do you want to do? "Well, I don't know, I simply want to shoot stuff." Unfortunately, that isn't a good answer. The kinds of equipment and skills required for different types of objects can vary considerably. What is appropriate for shooting moonscapes is very different from what is needed for shooting small galaxies. What is appropriate for shooting wide field shots of nebula is very different that what is best for imaging globular clusters. Unless you are very well off and can just buy anything you want, it is important to know what you want to image and then obtain equipment that will enable that to happen.
Where you want to shoot from can/should also influence your goals. Imaging from the center of a city is very different from imaging at a pristine dark site. Lunar and Planetary photography can be done almost anywhere. Objects like faint galaxies are going to be quite difficult from the center of a city and some compromises may need to be made (like using light pollution filters even though it will effect the color).
Where you want to shoot from can also influence how portable your equipment needs to be. Do you need to be able to load it into a car? Do you need to heft it out to the back yard? Do you have an observatory where it can stay setup?
I would suggest that you figure out an answer to at least the following questions before you purchase anything:
1) What do I want to image?
2) What are the conditions where I will be imaging?
3) How portable does my equipment need to be?
4) How much am I able to spend?
Those answers will shape your goals and they interact. For example, solar system imaging can often be done for less money than deep sky.
After answering those questions, formulate at least mentally what you want to achieve. An example would be, I want to do narrow band, wide field imaging of nebula from my red zone backyard observatory.
That will now put you in a position to acquire the necessary gear and skills required. That doesn't mean you can never do anything else. You might decide later on you want to add in doing wide field imaging of galaxies with a portable rig.
Penny Wise and Pound Foolish:
Astrophotography can be expensive. And many of us live on income that is modest. That means we need to be somewhat careful about throwing away money on gear we don't need. However, that can lead to penny pinching that is ultimately counterproductive. Sometimes, it is better to spend a little more upfront.
Let me give you an example. In the past, many people started guiding by getting the Orion StarShoot AutoGuider. It is currently selling for 259.99$. It was also very popular to get it with the 50mm finder package (currently 329.99$). That was a very attractive deal because other more capable guide cameras were very expensive. For example the SBIG ST-i was 499$ and up. The Lodestar was even more.
However, times have changed and much more attractive guide cameras have come on the market for only slightly more. A QHY5L-II mono can be had for 320$ (some are finding them for even less). This camera has higher quantum efficiency, which together with good noise characteristics means it pulls in more guide stars. That means a better chance of finding a star with good signal to noise ratio which effects your guiding. And should you ever switch to using an off-axis guider (OAG) the extra sensitivity will definitely be appreciated. The QHY5L-II mono also serves as an excellent lunar and planetary camera if that should become an interest because it will shoot video.
The difference in cost for the cameras is about 60$ or an increase of about 23%. If you want the guide scope you can buy that separately from Orion for 79.99$. Then the difference in cost is about 70$ or about 21%.
In my opinion that additional cost is very worthwhile.
Astrophotography can be expensive. And many of us live on income that is modest. That means we need to be somewhat careful about throwing away money on gear we don't need. However, that can lead to penny pinching that is ultimately counterproductive. Sometimes, it is better to spend a little more upfront.
Let me give you an example. In the past, many people started guiding by getting the Orion StarShoot AutoGuider. It is currently selling for 259.99$. It was also very popular to get it with the 50mm finder package (currently 329.99$). That was a very attractive deal because other more capable guide cameras were very expensive. For example the SBIG ST-i was 499$ and up. The Lodestar was even more.
However, times have changed and much more attractive guide cameras have come on the market for only slightly more. A QHY5L-II mono can be had for 320$ (some are finding them for even less). This camera has higher quantum efficiency, which together with good noise characteristics means it pulls in more guide stars. That means a better chance of finding a star with good signal to noise ratio which effects your guiding. And should you ever switch to using an off-axis guider (OAG) the extra sensitivity will definitely be appreciated. The QHY5L-II mono also serves as an excellent lunar and planetary camera if that should become an interest because it will shoot video.
The difference in cost for the cameras is about 60$ or an increase of about 23%. If you want the guide scope you can buy that separately from Orion for 79.99$. Then the difference in cost is about 70$ or about 21%.
In my opinion that additional cost is very worthwhile.
Equipment Only:
Acquistion of good data is only half the battle for astrophotography. That data still needs to be processed into an image that is pleasing to look at. That requires some kind of post processing software. Time after time I see people sink literally thousands of dollars into equipment, but they don't purchase the post processing software that will make their images really pop.
Furthermore, image processing is where you get to develop something of your own style. Do you like monochrome, high contrast images? Soft pastel colors? Bold, highly saturated vistas? Image processing can make that happen.
Don't make that mistake. Excellent post processing software can be had for reasonable prices. For example StarTools sells for just 60 Australian dollars. PixInsight sells for 190 Euros. Even Photoshop CS6 can still be had for 749$. I use and value all three. If I had to choose just one it would be PixInsight. But I'm glad I don't have to make that choice.
Acquistion of good data is only half the battle for astrophotography. That data still needs to be processed into an image that is pleasing to look at. That requires some kind of post processing software. Time after time I see people sink literally thousands of dollars into equipment, but they don't purchase the post processing software that will make their images really pop.
Furthermore, image processing is where you get to develop something of your own style. Do you like monochrome, high contrast images? Soft pastel colors? Bold, highly saturated vistas? Image processing can make that happen.
Don't make that mistake. Excellent post processing software can be had for reasonable prices. For example StarTools sells for just 60 Australian dollars. PixInsight sells for 190 Euros. Even Photoshop CS6 can still be had for 749$. I use and value all three. If I had to choose just one it would be PixInsight. But I'm glad I don't have to make that choice.
Image Hopping:
This is especially a problem for deep sky imagers. Just about everyone when they start out is like a kid in the candy store. There are so many great objects out there, and we want our own image of all of them, as quickly as possible.
Inevitably, this leads to a bunch of poor pictures.
There are at least two reasons for this. First we are in a rush and don't take time to do things right. For example, we might be lax on our polar alignment. Or maybe we aren't quite as careful focusing as we should be. Second, the amount of integration time you spend on an image directly influences the amount of noise. How long you need to spend on target depends a lot on the characteristics of the particular object. But most targets require hours. Here is a comparison I did with increasing amounts of integration time.
This is especially a problem for deep sky imagers. Just about everyone when they start out is like a kid in the candy store. There are so many great objects out there, and we want our own image of all of them, as quickly as possible.
Inevitably, this leads to a bunch of poor pictures.
There are at least two reasons for this. First we are in a rush and don't take time to do things right. For example, we might be lax on our polar alignment. Or maybe we aren't quite as careful focusing as we should be. Second, the amount of integration time you spend on an image directly influences the amount of noise. How long you need to spend on target depends a lot on the characteristics of the particular object. But most targets require hours. Here is a comparison I did with increasing amounts of integration time.
Too Accepting:
It is easy to fall into the trap of using everything you shoot, whether it is actually any good or not. But while all people may be created equal, all subs are not. Some need to be exterminated like a termite eating your house. Kill them with extreme prejudice. I think there are a couple of reasons why people do not do this:
1) They may have invested a lot of time in those subs.
2) They don't have an effective way of finding the bad ones and removing them.
As to the first reason, what you need to realize is that by adding bad subs, you are harming rather than helping your image be all that it can be. If it would actually help it, for the purpose of this discussion, it is a good sub.
As to the second reason, there are many image graders out there that aim to make this process simpler. To name a couple, there is an image grader within Sequence Generator Pro, there is a grader within CCD Inspector, and there is the SubframeSelector script in PixInsight. Personally, I use both the SGP and PixInsight graders but the PixInsight grader has more variables and makes it very easy to separate the good and bad subs based on expressions.
What variables are important? Certainly FWHM (or HFR) matters because it is a measure of how tight your stars are. Eccentricity matters because it measures how round your stars are (and thus reflects certain aspects of how well you are guiding). Signal to noise ratio (or number of stars), can give you an idea of when clouds rolled through, the Moon rose, or your mirror got dew bombed.
As time goes on you'll probably find the need to be more strict. Again, the criteria is whether a sub will improve or hurt the image as a whole. When you start out, you may have NO subs with round stars. That is OK. You don't need to just toss them all away. Likewise, you'll probably find the tightness (FWHM) of your stars improves over time. That was certainly the case for me.
I actually select my criteria on an image by image basis. For example, my stars weren't quite as tight as normal with Messier 20 because the object is so far south it never gets very high. I looked at what was normal and then threw out the outliers.
It is easy to fall into the trap of using everything you shoot, whether it is actually any good or not. But while all people may be created equal, all subs are not. Some need to be exterminated like a termite eating your house. Kill them with extreme prejudice. I think there are a couple of reasons why people do not do this:
1) They may have invested a lot of time in those subs.
2) They don't have an effective way of finding the bad ones and removing them.
As to the first reason, what you need to realize is that by adding bad subs, you are harming rather than helping your image be all that it can be. If it would actually help it, for the purpose of this discussion, it is a good sub.
As to the second reason, there are many image graders out there that aim to make this process simpler. To name a couple, there is an image grader within Sequence Generator Pro, there is a grader within CCD Inspector, and there is the SubframeSelector script in PixInsight. Personally, I use both the SGP and PixInsight graders but the PixInsight grader has more variables and makes it very easy to separate the good and bad subs based on expressions.
What variables are important? Certainly FWHM (or HFR) matters because it is a measure of how tight your stars are. Eccentricity matters because it measures how round your stars are (and thus reflects certain aspects of how well you are guiding). Signal to noise ratio (or number of stars), can give you an idea of when clouds rolled through, the Moon rose, or your mirror got dew bombed.
As time goes on you'll probably find the need to be more strict. Again, the criteria is whether a sub will improve or hurt the image as a whole. When you start out, you may have NO subs with round stars. That is OK. You don't need to just toss them all away. Likewise, you'll probably find the tightness (FWHM) of your stars improves over time. That was certainly the case for me.
I actually select my criteria on an image by image basis. For example, my stars weren't quite as tight as normal with Messier 20 because the object is so far south it never gets very high. I looked at what was normal and then threw out the outliers.
Not Enough Practice:
In most endeavors, it takes a certain amount of practice to get competent, let alone really good. You don't pick up golf clubs and shoot par the next day. You don't pick up a guitar, and play like Hendrix without a lot of serious time and effort. One guy wrote a book that asserts that it takes about 10,000 hours of concerted practice to master an activity, whether it is guitar, golf, cooking, or programming a computer. If you want to be a master at it, you have to put in the time. He also asserts that talent is overrated. (The book is called "Outliers: The Story of Success" and is written by Malcolm Gladwell). I personally believe talent does matter. However, it is true that a LOT of practice is generally necessary to get really good at something.
In the case of astrophotography, that applies to both acquiring the data, and to processing it.
Now most of us are probably never going to end up spending 10,000 hours doing astrophotography. And that is alright. But it is a mistake to think that competence can be had without the attendant level of effort. This is not an area where you can buy your way to success. It is perfectly possible to spend 10,000$ on an imaging rig, and produce pictures that suck. In fact, you could spend 2.5 Billion on a rig and still produce bad pictures. If you don't believe me, the Hubble Archive is available to anyone who wants to give it a try. It will take time and effort to learn to produce much with the data.
I'm not saying a better rig might not help. I am saying you have to do the time. The image below was the second shot with my SBIG-STF-8300m camera. I think it makes my point.
In most endeavors, it takes a certain amount of practice to get competent, let alone really good. You don't pick up golf clubs and shoot par the next day. You don't pick up a guitar, and play like Hendrix without a lot of serious time and effort. One guy wrote a book that asserts that it takes about 10,000 hours of concerted practice to master an activity, whether it is guitar, golf, cooking, or programming a computer. If you want to be a master at it, you have to put in the time. He also asserts that talent is overrated. (The book is called "Outliers: The Story of Success" and is written by Malcolm Gladwell). I personally believe talent does matter. However, it is true that a LOT of practice is generally necessary to get really good at something.
In the case of astrophotography, that applies to both acquiring the data, and to processing it.
Now most of us are probably never going to end up spending 10,000 hours doing astrophotography. And that is alright. But it is a mistake to think that competence can be had without the attendant level of effort. This is not an area where you can buy your way to success. It is perfectly possible to spend 10,000$ on an imaging rig, and produce pictures that suck. In fact, you could spend 2.5 Billion on a rig and still produce bad pictures. If you don't believe me, the Hubble Archive is available to anyone who wants to give it a try. It will take time and effort to learn to produce much with the data.
I'm not saying a better rig might not help. I am saying you have to do the time. The image below was the second shot with my SBIG-STF-8300m camera. I think it makes my point.
Too Set in Their Ways:
It is very tempting to find a method that works for you and then rest on your laurels. That may produce a consistent product of a given quality level. But it isn't a good way to advance your skills. If you want to advance, you have to take chances, and you need to try new things. If they don't work, fine, go back to what has been working for you. But at least try. I also recommend that you try things for yourself rather than just accepting what you heard on the forums. I am constantly experimenting. Just how bad does the Moon effect your images? How do you know without trying? Just how long an exposure can you make before flexure becomes an issue? Which noise reduction technique works best, ACDNR or TGVDenoise?
This applies to both the image acquisition and image processing sides of the hobby.
Not all experiments are going to be a success. That is OK. But you'll learn something along the way. And some of the experiments will work out and the quality of your images will get better.
It is very tempting to find a method that works for you and then rest on your laurels. That may produce a consistent product of a given quality level. But it isn't a good way to advance your skills. If you want to advance, you have to take chances, and you need to try new things. If they don't work, fine, go back to what has been working for you. But at least try. I also recommend that you try things for yourself rather than just accepting what you heard on the forums. I am constantly experimenting. Just how bad does the Moon effect your images? How do you know without trying? Just how long an exposure can you make before flexure becomes an issue? Which noise reduction technique works best, ACDNR or TGVDenoise?
This applies to both the image acquisition and image processing sides of the hobby.
Not all experiments are going to be a success. That is OK. But you'll learn something along the way. And some of the experiments will work out and the quality of your images will get better.
Unrealistic Expectations:
This is a hobby where equipment and other factors do matter. Your equipment cannot make you good, but it absolutely can and does put a limit on what you can achieve. The same is true of other conditions. For example, the light pollution level will make a difference. You may or may not be able to capture things like the Integrated Flux Nebula (IFN) based on your site.
The same is true with your experience. As mentioned above it simply takes a certain amount of dedicated practice to get to a given skill level. Your stars are simply not going to be as tight at first. You don't know how to focus properly. You don't know how to get the most out of your mount. You don't know how to process to control star bloat. Those things come with time and practice.
It is fine to have goals. In is fine to have expectations. But keep them realistic. To do otherwise leads to discouragement. And discouragement can lead to quitting.
What I recommend is every time you take an image, look at the result critically. What went right? What went wrong? Why? Can something be improved? Can you get where you want to be with what you have or do you need to change things up?
For example, I knew I that I was limited in the length of subs I could take with a finder guider on my AT8RC. Differential flex was an issue. It was working OK for 5m subs, but I wanted to be able to take much longer subs for narrow band work that I would like to get into. I bought an Off Axis Guider (OAG). When I used my new OAG, I had problems finding guide stars, and the ones I could find had poor signal to noise. At that point I could have just become discouraged and quit. Instead I analyzed the problem. I was using a SBIG ST-i color. Problem one was it was a color, not mono guide camera. Problem two, and related was that QE was not as good as it needed to be. I purchased a QHY5L-II mono. Things are now much better and the OAG is working very well.
And don't get trapped by comparing yourself to others. I didn't say don't compare yourself to others. I said don't get trapped by comparing yourself to others. You may be able to learn something by looking at the work of others. That is a good thing. Maybe you like the noise reduction in their images. Try to find out what they do. But at the same time realize they probably have different equipment, they almost certainly have different conditions, and different experience. Maybe your images aren't as good as theirs yet. But don't be discouraged. Time and work can improve what you are doing. At the same time, you can be trapped by thinking you are better than you are. That can lead to laziness and stagnation.
Try to realistically assess where you are, and set your expectations and goals accordingly. Analyze what you are doing, and determine how to improve. Pick one thing that can be improved and work on that. Don't be discouraged, be determined.
This is a hobby where equipment and other factors do matter. Your equipment cannot make you good, but it absolutely can and does put a limit on what you can achieve. The same is true of other conditions. For example, the light pollution level will make a difference. You may or may not be able to capture things like the Integrated Flux Nebula (IFN) based on your site.
The same is true with your experience. As mentioned above it simply takes a certain amount of dedicated practice to get to a given skill level. Your stars are simply not going to be as tight at first. You don't know how to focus properly. You don't know how to get the most out of your mount. You don't know how to process to control star bloat. Those things come with time and practice.
It is fine to have goals. In is fine to have expectations. But keep them realistic. To do otherwise leads to discouragement. And discouragement can lead to quitting.
What I recommend is every time you take an image, look at the result critically. What went right? What went wrong? Why? Can something be improved? Can you get where you want to be with what you have or do you need to change things up?
For example, I knew I that I was limited in the length of subs I could take with a finder guider on my AT8RC. Differential flex was an issue. It was working OK for 5m subs, but I wanted to be able to take much longer subs for narrow band work that I would like to get into. I bought an Off Axis Guider (OAG). When I used my new OAG, I had problems finding guide stars, and the ones I could find had poor signal to noise. At that point I could have just become discouraged and quit. Instead I analyzed the problem. I was using a SBIG ST-i color. Problem one was it was a color, not mono guide camera. Problem two, and related was that QE was not as good as it needed to be. I purchased a QHY5L-II mono. Things are now much better and the OAG is working very well.
And don't get trapped by comparing yourself to others. I didn't say don't compare yourself to others. I said don't get trapped by comparing yourself to others. You may be able to learn something by looking at the work of others. That is a good thing. Maybe you like the noise reduction in their images. Try to find out what they do. But at the same time realize they probably have different equipment, they almost certainly have different conditions, and different experience. Maybe your images aren't as good as theirs yet. But don't be discouraged. Time and work can improve what you are doing. At the same time, you can be trapped by thinking you are better than you are. That can lead to laziness and stagnation.
Try to realistically assess where you are, and set your expectations and goals accordingly. Analyze what you are doing, and determine how to improve. Pick one thing that can be improved and work on that. Don't be discouraged, be determined.