Basics:
Astro photography has always been a fascination of mine, I love landscapes, and being able to see the stars paint the night sky is still mesmerizing for me every time. This video is the third, and kind of the conclusion of series of videos focusing on long exposure photography. I really recommend watching those video on long exposures and timelapses first before diving into this one just because of how relatively complicated photos of stars can be, it requires pushing your gear to really the limits of what it is capable of in the night when its usually pretty cold out, so being comfortable with getting your settings nailed down and how to set up your camera is of utmost importance. With that said though, if you already are proficient with long exposures and timelapses, or just want to hit the ground running, I will cover all the basics here.
What you will need:
I’ll start off with what gear you are going to need: The most important thing you will need is a tripod, it doesn’t need to be fancy, but it does need to be there to keep you camera still as you capture picture. Typically, though, the heavier the tripod is, the better, and if you have a bag you can weight it down with, that’s even more ideal.
You also will obviously need a camera, I am going to be focusing on full frame sony cameras like the a7iii, but all the same principles apply to the crop sensor camera like the a6000, 6400 and a6600 or cameras from other brands. As far as what lens you’ll need goes, you’ll need to go fast and wide. I started off using a canon 17-40mm f4 and now use a Zeiss batis 18mm f2.8. The reason why wide angle lenses work better will become clear later in the video, but essentially the wider the angle, the longer the exposure you can get. The smaller the aperture number is also allows more light into your camera, also allowing you to get more light in in less time. Also, don’t forget warm cloths, a flashlight and snacks!
Planning your shot
The next important step is planning when and where you want to go for your photo, Unfortunately nowadays light pollution is an incredibly common thing and generally speaking you wanna get out of town and as far away from a population centre as possible. There are handy websites like lightpollutionmap.info that help show where there is the least light pollution and also there are certain townships that you can look up in your area that are designated night Sky safe areas, it might take awhile to find the best spot, but for instance here in Ontario a perfect location is tobermory or anywhere on the Bruce Peninsula.
The next tricky part is once you know what good location is knowing the right time to go out, you’re gonna want to become familiar with when there’s gonna be a moon in the sky because the moon will somewhat destroy your image if you’re there to capture the stars because it’s going to not only increase the amount of light pollution in the atmosphere it’s also going to light up your foreground significantly, there are many apps out there that can help you figure out the lunar calendar and when it’s gonna be a new moon, or when the moon sets.
Knowing how much clouds there will be in the sky is also important, you want to go out when the sky is as clear as possible and when there’s gonna be the least humidity realistically if there are some clouds in the sky you can still capture an image quite easily because it is going to be a long exposure and if they’re moving they’re only going to be covering part of the image however to get that perfect photo is nice to have an empty sky.
The last thing to keep in mind is to know where the North such star, Polaris, is if you’re in the northern hemisphere because pointing your image at the North star will have the stars spiral around that point. Unfortunately if you’re in the southern hemisphere you’re going to have to use and app to find the milky way, there are many apps to help out with this though the one I use is called star walk 2, but really if you look up star app in your phone’s App Store you’ll find something that works.
Setting up the camera
So now that we got choosing your shot nail down I’m gonna talk about what we’re gonna need to prep in the camera before we go out into the field. there are a lot of concepts that carry over from the long exposure photography and the time lapse photography videos i made And I hate to beat it at horse but if you haven’t seen those videos they will help out a lot before you jump into shooting stars.
The fundamental aspect of star photography is finding the balance between having a long exposure image but also not capturing star trails on your stars if you want sharp images of individual stars. there is no real sweet spot for settings between every Camera Unfortunately that I can say this will work every time because the size of the sensor the amount of megapixels on the sensor in the focal length of the lens you are using will all affect how long your exposure can be. I apologise for how convoluted this is going to sound because it is quite a complicated subject and i’m not a mathematician so it’s not gonna be explained most likely by myself in the most eloquent way.
For long exposure photography of the stars there is the 500 rule which basically divides 500 by your focal length and sensor size to calculate a recommended exposure time. The issue with this rule is it accounts for a lower sized images, in most cameras sensors nowadays are 24mp or more, so this doesn’t necessarily indicate the best shutter speed to use and you often will end up wanting to go faster however it does give you a reliable number to start with and at the end of the day it’s going to vary camera to camera. The lonely speck is a fantastic YouTube channel they also have great website with a calculator on it, I highly recommend checking out their work.
As far the my most basic common settings go, I end up starting with an ISO of 1000-8000 in aperture of F 2.8 in a shutter speed 15 seconds this is on my A7R3 with the 42 megapixel sensor and an 18mm lens, however these settings will be completely dependant on your lighting and your gear.
Star stack
Once we have an image edited though it is quite simple to turn it into a time lapse an I covered that previously in my video on time lapses so I’m not going to touch on it again heavily but all you want to do is simply export the images in sequence and then render them out as a time lapse in premiere or whatever software you prefer to use to make a time lapse in. however if you want to get a little bit more fancy in have some star trails added to your photos you can use a program called star stax. With this software you can add the star trails to the tails of your stars to give them that swirling effect that is coveted for a lot of nighttime timelapses.
The software is free and incredibly easy to use, all you need To do is open up the software import the images that you would like to turn into the timelapse choose save after each clip put it to comet mode and gap filling. From here all you need to do is to just click the render button and you’re good to go. if you’d like to make one single image of all the layers stacked together to have the spiral look of stars all the way across the Sky all you need to do is to Simply put it in gap filling mode and you’re good to go again and just hit render an it will render it all out as one image rather than multiple.
It’s as easy as that though, there are many settings within the software where you can adjust the sensitivity and tolerances of the program to decide what it discerns is a star in for how long the startrails should go for however a lot of your work is going to end up being trial and error and seeing what you like best. the main tip I’ll give is that if you do plan on stacking the images like this just keep in mind that sometimes less is more because if you have too many small stars in the Sky the software is just going to see all those stars and blend them together whereas if you have a very pretty Sky with a good amount of just bright stars it might actually look a little bit nicer for the startrails this is also awesome because you can have a image that might not be as strong independently however if you put it into a timelapse it can turn into a very nice time lapse still even though the sky wasn’t as dark as you would have liked.
Once you’re done all this though you can just do the same thing as you did with the independent images to make a timelapse and pull them into Adobe premiere or your preferred software and make a time lapse from the images and it’s as easy as that!
Conclusion:
well once again this has been an incredibly long post in thank you for sticking with it until the end. I hope you enjoyed this series of tutorials and if you enjoyed it I would really appreciate if you share it with your friends. I really appreciate all the support I get from you guys though and I do enjoy making these so thank you for the opportunity to do what I love.
Shane Bethlehem Photography 