Photographing Star Trails
"Star Trails" as a term is a bit of a misnomer because stars do not leave trails but it is the widely accepted term used to describe the photographic method of shooting the stars. For any of you that have spent any time looking up at the stars you may have noticed that they appear to be moving across the sky. The fact of the matter is that it is not the stars that are moving; it is the earth that is rotating on its axis. So, the way to think about Star Trails is simple, it is really you, your camera, your tripod and the ground that you are standing on doing all the spinning. The great part about shooting Star Trails is that your camera does most of the work while you are free to do other things like watch a movie, go to bed or do what I do and process your images from the night before. I will describe that later and include some great links for processing your images.
Shooting Method and Equipment
My method for shooting is with a DSLR camera. I have not tried shooting with a Digital Point and Shoot so please be aware of that, the shooting method with a Digital Point and Shoot, may be different. The equipment needed is a DSLR Camera with a lens (wide angle preferred) and a tripod. The software to process your images is Photoshop CS3 and up.
Star Trails are achieved by shooting many images over a long period of time. Each image is then processed in Photoshop and stacked together to create a final image. The most important thing to remember is that once you are set up and ready to start shooting, the camera and the tripod can not be moved or even touched. This means you will need an Intervalometer to control the settings of how many shots you want to take and to control your Bulb setting for exposure. Most DSLR cameras that have these setting options are in the expensive range of DSLR's. One option would be to purchase a separate control or seek out the web to find software that will do it but this also means having to use a computer while shooting.
For those of you that have a Canon T1i or any Rebel and up for that matter here is the simple solution, Magic Lantern. Magic Lantern is freeware that unleashes the power from your Canon DSLR. The Software does not change any of the original settings your camera came with because the software is stored on your memory card. I have been using it for a while now and it works great. It also has many more features than just Intervalometer and Bulb. The list is far too large for me to list here so check it out for yourself, you will love it. Here is the link. http://www.magiclantern.fm/ Please be aware that Magic Lantern was designed for Canon Cameras only and I do not recommend trying it out with other camera manufacturers.
Once you are ready to start shooting your images, the best thing to do first is to take a few test shots to be sure you are happy with the composition. It is always best to have some sort of a foreground to give you some depth. This can even be done during the day or early evening. Take note of how much sky you have compared to the foreground. More sky is aways best like in the image above. Once you have decided on your composition and nightfall has set in, it is time to get your settings correct on your camera. This is another period for some test shots. Before you take your test shots make sure the mirror is in "MIRROR LOCKUP" mode. The camera in the above image was set at ISO 400, Aperture f/4 and exposure at 35 seconds, WB set on Tungsten and the lens set at infinity shooting in RAW mode with a total of 300 images. The Bulb setting, using the Magic Lantern software was set at 35 sec with the Intervalometer set to take an image 1 sec after each shot for 300 shots. These settings are not a rule because your light conditions may be very different from mine but they may be a starting point.
Shooting Tips
1. Be sure to take your images in RAW mode. Raw mode has far more options for processing your images. Raw Files can be opened in Photoshop. It is very much like having your own little darkroom for developing. It is also not necessary to write down the settings for each test shot because that information can be found when you open the RAW file. There is a link below for Batching your RAW files when you get to the processing part of this tutorial
2. I would also suggest that you look at your test shots on your computer before setting the camera for the final series of images. This will allow you to double check focus and more importantly clarity of the stars. Once you have gone through the test shots and have found the setting you like just write down the setting that is on the RAW file you have chosen and now you are ready to start shooting. Please note that once you get used to your camera settings and have done this a few times you will most likely get to the point of not needing to shoot test shots or you will just be able to tell if they are working right from the cameras screen.
3. Setting up the Intervalometer and the Bulb setting is quite simple with the Magic Lantern software. You are basically setting up the time exposure with the Bulb setting and the amount of time between each shot and how many shots with the Intervalometer. I have come to discover that shooting fewer images with a longer exposure is not the best way to go. Longer exposure produces more noise and because the Aperture needs to be a higher number (less light) faint stars do not show up very well. In the sample image above my settings were set at the following; ISO-400, Aperture f/9 and exposure at 180 sec. As you can see the results are not too great. In my defence there was a Waning Gibbous Moon over head, I will get into the moon later. Bottom line is a shorter Exposure like 30-40 sec with a lower aperture like f/3.5 will produce more stars. As for the number of shots the above image is only 118 shots in the stack which produced almost 6 hours of shooting time. The image below is around the same amount of time, 6 hours but the exposure was 35 sec for a total of 600 shots. Bottom line, more images less exposure produces a better final image.
3. Setting up the Intervalometer and the Bulb setting is quite simple with the Magic Lantern software. You are basically setting up the time exposure with the Bulb setting and the amount of time between each shot and how many shots with the Intervalometer. I have come to discover that shooting fewer images with a longer exposure is not the best way to go. Longer exposure produces more noise and because the Aperture needs to be a higher number (less light) faint stars do not show up very well. In the sample image above my settings were set at the following; ISO-400, Aperture f/9 and exposure at 180 sec. As you can see the results are not too great. In my defence there was a Waning Gibbous Moon over head, I will get into the moon later. Bottom line is a shorter Exposure like 30-40 sec with a lower aperture like f/3.5 will produce more stars. As for the number of shots the above image is only 118 shots in the stack which produced almost 6 hours of shooting time. The image below is around the same amount of time, 6 hours but the exposure was 35 sec for a total of 600 shots. Bottom line, more images less exposure produces a better final image.
IMPORTANT TIPS TO TAKE NOTE OF
1. Your CAMERA will most likely be left alone outside while you sleep. I can't stress enough how important it is to check the weather in your area before shooting. Water and electronics do not get on well together at all. I use Weather Underground to check the weather, here is the link. http://www.wunderground.com
2. The moon will have an effect on your images. If the moon is up, shoot in the opposite direction like north east or north west or towards Polaris or wait until the moon is not visible in the night sky. The moon acts like a giant light bulb so be aware that if you are shooting while the moon is up you will most likely capture less stars in your images. Here is a great site that will tell you where the moon is going to be on any given day. Keep in mind the moon orbits the earth every 29.5 days and spends half of those days up at night and the other during the day.www.moonconnection.com
3. Be aware of any high winds or if they are in the forecast. Wind will have an effect on your foreground if it happens to be trees, the motion of the trees will produce a blurred looking foreground. If you live in an area that is prone to gusts during the night I recommend weighting down your tripod but also check what weight it can handle first.
4. Knowing ahead of time that you are going to be shooting lots of RAW images, memory becomes really important. A single RAW photo shot with my T1i (15mp) is 17.3mb, so over the course of the night shooting 600 images that works out to 10.38gb. I use a 32gb SD card to be on the safe side. This is also my dedicated memory card with the "Magic Lantern" software stored on it.
5. Be sure your batteries are fully charged. If you have a battery grip, use it. I even re-charge the batteries after test shots seeing as I usually have time before setting the final shoot up. It may not seem like a big deal but that one last shot may have something really cool in it like a Fireball Meteor. If you only have one battery, set your Intervalometer to a high number anyway, the camera will just simple shut down by itself when the battery gets too low.
6. Clouds can be a hindrance or they can look cool. The bad ones are the ones you can't see through but wispy clouds can produce some cool final images.
7. If you have a neighbor's like mine that has one of those motion detection security lights that comes on in the middle of the night try shooting away from the direct light source. In my situation the neighbors light has come on from time to time but never for a long period. The first time it happened I though I had lost a whole night of shooting but it added some great light to the foreground. Just remember to not shoot directly towards the source or any other bright light source for that matter.
8. After I have dragged all my Raw files over to my computer I DO NOT delete them off of the memory card in the camera until all the processing is done and a final image has been created. The main reason for this is because I will be batching the RAW files with changes and if I do not like the setting I have chosen during the batching I still have the Raw Files on the memory card to start again. I could make a duplicate copy on the computer but really why add another 10gb to my machine if I don't need to.
9. It is always best to shoot after 11:00pm. The reason for this is that air traffic slows down quite a bit. If you can hold out until 1:00am to start shooting, even better. If there are one or two plane trails in the image, no biggy, they can be painted out using the stamp tool in Photoshop. If there are many, that is a pain and it takes lots of time to get rid of them.
Processing Your Images
So you have now taken your 300-800 images and now you need to process them. The set up for processing does not take long at all but the amount of time the computer needs is quite a while so it is always best to set the processing on your computer when you have something else you need to attend to like making dinner or washing the car. I strongly recommend that while your computer is processing, all other applications are closed. Do not attempt to do anything else with your computer once you have hit the start button.
There are two steps to processing your images in Photoshop. The first step is to change all you Raw files into Tiff files. I choose Tiff only because the color spectrum is much higher and a tiff can be changed to 16bit for working on your final image. 16bit offers a higher color range and therefore better blending when two colors come together. Once you have done all your adjusting to your final image and you are super happy with it you can change your Tiff back to 8bit and save as a jpeg which will be like a copy of your final Tiff. Back to processing. In order to change your RAW files into tiffs without having to do them one at a time, a process of Batching is used in Photoshop. You will simply set up one Tiff and let the computer do all the work. Here is a link for Batching all your RAW files and turning them into Tiffs. http://ronbigelow.com/articles/batch/batch.htm This is just Step one.
Okay so now you have a whole pile of Tiffs that will become your final image. It is now time for a second batching process in Photoshop. But, before you start have a look at all your Tiffs to make sure there are no weird anomalies like planes, clouds or flying saucers. The next step is done with an action that was created by Star Circle Academy. Here is the link. http://blog.starcircleacademy.com/2011/02/automated-stacking-of-star-trails-in-ps-cs5/ Just follow the steps in the link and let the magic happen. This process too will take a while so be sure to set it when you have other things to do. Again, do not have other applications running while doing this step.
When the stacking of your Star Trails has finished be sure to save the final tiff right away. I like to save it as the Raw Tiff and then when I have made some changes with all the Photoshop tools I then version the changes. Before making changes to the Tiff be sure to change the Tiff from 8bit to 16bit. And when you are ready to save a jpeg just switch the Tiff back to 8bit but save that final Tiff too in case you want to go back at a later date to make more changes.
I will be honest, the first time I looked at this process I was a little overwhelmed. I thought man oh man there are a lot of steps but really it is the written words that make it look like that. After you have done this two or three times you will be a pro. The final results are really cool and will be something to be proud of and to share with family and friends.
Below are some of my Star Trails. All of these were shot in my backyard. I am waiting for the day when I can get out and shoot a really cool vista like Yosemite, on a cliff by the ocean or just a great forest with a lake. I will continue to add to this tutorial as I learn more about shooting Star Trails so please check back from time to time or Join my site for automatic updates. If you have any questions or comments please feel free to email me, my address is on my home page at the top on the right.
For more GREAT tips on shooting
Star Trails click here
Backyard Star Trails
This was my first Star Trail. Shooting NE ISO-400, f/9, Exp 180sec, 118 images total. The mistake I made with this was doing such a long exposure, shorter exposures work much better. I now shoot at around 35 sec per exposure. As you scroll through the first three images you can see the noticable difference between long exposure and short exposure.
This capture is the same as the one before it. The only difference is I processed it with the clouds and the bright security light that came on from the backyard neighbor's house.
ISO-400, f/4.5, Exp 120sec, 180 images total
Shooting NNW of Polaris. ISO-400, f/11, Exp 150sec, 154 images total
Shooting W. ISO-400, f/4, Exp 35sec, 300 images total
Shooting E. ISO-400, f/4, Exp 35sec, 300 images total
1. Your CAMERA will most likely be left alone outside while you sleep. I can't stress enough how important it is to check the weather in your area before shooting. Water and electronics do not get on well together at all. I use Weather Underground to check the weather, here is the link. http://www.wunderground.com
2. The moon will have an effect on your images. If the moon is up, shoot in the opposite direction like north east or north west or towards Polaris or wait until the moon is not visible in the night sky. The moon acts like a giant light bulb so be aware that if you are shooting while the moon is up you will most likely capture less stars in your images. Here is a great site that will tell you where the moon is going to be on any given day. Keep in mind the moon orbits the earth every 29.5 days and spends half of those days up at night and the other during the day.www.moonconnection.com
3. Be aware of any high winds or if they are in the forecast. Wind will have an effect on your foreground if it happens to be trees, the motion of the trees will produce a blurred looking foreground. If you live in an area that is prone to gusts during the night I recommend weighting down your tripod but also check what weight it can handle first.
4. Knowing ahead of time that you are going to be shooting lots of RAW images, memory becomes really important. A single RAW photo shot with my T1i (15mp) is 17.3mb, so over the course of the night shooting 600 images that works out to 10.38gb. I use a 32gb SD card to be on the safe side. This is also my dedicated memory card with the "Magic Lantern" software stored on it.
5. Be sure your batteries are fully charged. If you have a battery grip, use it. I even re-charge the batteries after test shots seeing as I usually have time before setting the final shoot up. It may not seem like a big deal but that one last shot may have something really cool in it like a Fireball Meteor. If you only have one battery, set your Intervalometer to a high number anyway, the camera will just simple shut down by itself when the battery gets too low.
6. Clouds can be a hindrance or they can look cool. The bad ones are the ones you can't see through but wispy clouds can produce some cool final images.
7. If you have a neighbor's like mine that has one of those motion detection security lights that comes on in the middle of the night try shooting away from the direct light source. In my situation the neighbors light has come on from time to time but never for a long period. The first time it happened I though I had lost a whole night of shooting but it added some great light to the foreground. Just remember to not shoot directly towards the source or any other bright light source for that matter.
8. After I have dragged all my Raw files over to my computer I DO NOT delete them off of the memory card in the camera until all the processing is done and a final image has been created. The main reason for this is because I will be batching the RAW files with changes and if I do not like the setting I have chosen during the batching I still have the Raw Files on the memory card to start again. I could make a duplicate copy on the computer but really why add another 10gb to my machine if I don't need to.
9. It is always best to shoot after 11:00pm. The reason for this is that air traffic slows down quite a bit. If you can hold out until 1:00am to start shooting, even better. If there are one or two plane trails in the image, no biggy, they can be painted out using the stamp tool in Photoshop. If there are many, that is a pain and it takes lots of time to get rid of them.
Processing Your Images
So you have now taken your 300-800 images and now you need to process them. The set up for processing does not take long at all but the amount of time the computer needs is quite a while so it is always best to set the processing on your computer when you have something else you need to attend to like making dinner or washing the car. I strongly recommend that while your computer is processing, all other applications are closed. Do not attempt to do anything else with your computer once you have hit the start button.
There are two steps to processing your images in Photoshop. The first step is to change all you Raw files into Tiff files. I choose Tiff only because the color spectrum is much higher and a tiff can be changed to 16bit for working on your final image. 16bit offers a higher color range and therefore better blending when two colors come together. Once you have done all your adjusting to your final image and you are super happy with it you can change your Tiff back to 8bit and save as a jpeg which will be like a copy of your final Tiff. Back to processing. In order to change your RAW files into tiffs without having to do them one at a time, a process of Batching is used in Photoshop. You will simply set up one Tiff and let the computer do all the work. Here is a link for Batching all your RAW files and turning them into Tiffs. http://ronbigelow.com/articles/batch/batch.htm This is just Step one.
Okay so now you have a whole pile of Tiffs that will become your final image. It is now time for a second batching process in Photoshop. But, before you start have a look at all your Tiffs to make sure there are no weird anomalies like planes, clouds or flying saucers. The next step is done with an action that was created by Star Circle Academy. Here is the link. http://blog.starcircleacademy.com/2011/02/automated-stacking-of-star-trails-in-ps-cs5/ Just follow the steps in the link and let the magic happen. This process too will take a while so be sure to set it when you have other things to do. Again, do not have other applications running while doing this step.
When the stacking of your Star Trails has finished be sure to save the final tiff right away. I like to save it as the Raw Tiff and then when I have made some changes with all the Photoshop tools I then version the changes. Before making changes to the Tiff be sure to change the Tiff from 8bit to 16bit. And when you are ready to save a jpeg just switch the Tiff back to 8bit but save that final Tiff too in case you want to go back at a later date to make more changes.
I will be honest, the first time I looked at this process I was a little overwhelmed. I thought man oh man there are a lot of steps but really it is the written words that make it look like that. After you have done this two or three times you will be a pro. The final results are really cool and will be something to be proud of and to share with family and friends.
Below are some of my Star Trails. All of these were shot in my backyard. I am waiting for the day when I can get out and shoot a really cool vista like Yosemite, on a cliff by the ocean or just a great forest with a lake. I will continue to add to this tutorial as I learn more about shooting Star Trails so please check back from time to time or Join my site for automatic updates. If you have any questions or comments please feel free to email me, my address is on my home page at the top on the right.
For more GREAT tips on shooting
Star Trails click here
Backyard Star Trails
This was my first Star Trail. Shooting NE ISO-400, f/9, Exp 180sec, 118 images total. The mistake I made with this was doing such a long exposure, shorter exposures work much better. I now shoot at around 35 sec per exposure. As you scroll through the first three images you can see the noticable difference between long exposure and short exposure.
This capture is the same as the one before it. The only difference is I processed it with the clouds and the bright security light that came on from the backyard neighbor's house.
ISO-400, f/4.5, Exp 120sec, 180 images total
Shooting NNW of Polaris. ISO-400, f/11, Exp 150sec, 154 images total
Shooting W. ISO-400, f/4, Exp 35sec, 300 images total
Shooting E. ISO-400, f/4, Exp 35sec, 300 images total
Venus Rising, Shooting WSW. ISO-400, f/4, Exp 35sec, 406 images total. The big white
streak is Venus Rising
Shooting N towards Polaris. ISO-400, f/4, Exp 35sec, 600 images total
The nice part about shooting Star Trails is you sometimes get a cool suprise. In this case,
a meteor from the Orionid Meteor Shower.
The two Meteor images above were captured within one minute of each other.
This is a composite of the two Meteors captured within one minute of each other in two 30sec exposures.
Shooting NW ISO-400, f/4, Exp 30sec 606 images total.
Shooting SE ISO-400, f/4, Exp 35 sec, 598 images total. Venus is the large trail on the left, rising in the morning. The house is being lit by my neighbor's security light.
Shooting west ISO-400 f/4, Exp 35sec, 673 images total. The images were captured with a 10-22mm wide angle lens set at 22mm. The distortion on the right towards Polaris is due to the 10mm wide angle.
Shooting true north right at Polaris. ISO-400, f/4, Exp 35sec, 667 images total. Captured with a 10-20mm wide angle lens set at 10mm. The light spikes/beams at the bottom were just a happy mistake. The light is coming from 2 small wall lights located in the wall 2" up from the ground
Shooting north just a bit to the west of Polaris. ISO-400, f/4.5, 35sec Exp, 433 images total. 18-55mm lens @ 18mm. Star Valley near Tucson AZ
a meteor from the Orionid Meteor Shower.
The two Meteor images above were captured within one minute of each other.
This is a composite of the two Meteors captured within one minute of each other in two 30sec exposures.
Shooting NW ISO-400, f/4, Exp 30sec 606 images total.
Shooting SE ISO-400, f/4, Exp 35 sec, 598 images total. Venus is the large trail on the left, rising in the morning. The house is being lit by my neighbor's security light.
Shooting west ISO-400 f/4, Exp 35sec, 673 images total. The images were captured with a 10-22mm wide angle lens set at 22mm. The distortion on the right towards Polaris is due to the 10mm wide angle.
Shooting true north right at Polaris. ISO-400, f/4, Exp 35sec, 667 images total. Captured with a 10-20mm wide angle lens set at 10mm. The light spikes/beams at the bottom were just a happy mistake. The light is coming from 2 small wall lights located in the wall 2" up from the ground
Shooting true north at Polaris. ISO-200, f/6.3, 35sec Exp, 454 images total. 18-55mm lens @ 18mm. The images were captured in a place just west of downtown Tucson AZ called "Star Valley". The color of the sky is pretty close to what it looked like at 1:00am on may 25th, the sky never really got dark.
Shooting north just a bit to the west of Polaris. ISO-400, f/4.5, 35sec Exp, 433 images total. 18-55mm lens @ 18mm. Star Valley near Tucson AZ
Woah that was amazing. I mean your photography skills are incredible. I once tried to capture the star trail but ended up in achieving nothing. Thanks for your expert advice.
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