Having lived in urban cities with light pollution, the beauty of the dark sky was always blind to us.
Astrophotography has to be the most fascinating genre of photography since it allows us to peek into what lies above and beyond us.
A humble caution before you proceed further- Although this article is aimed at beginners, a few basic technical terms about photography such as exposure, aperture, ISO, etc are used. For a better understanding, I suggest you read my article on Camera Basics and Exposure Triangle before proceeding further.
While astrophotography is interesting, it can be equally intimidating. Astrophotography itself is as vast as the universe. This article is intended for beginners trying to venture into Astrophotography so to keep things simple, I will be focusing on using only basic tools such as a Camera and Tripod.
You might've heard of fancy equipment such as Star Trackers, Telescopes, and filters but I can assure you that they are not needed to shoot the stars, moon, milky way, etc. So worry no more and let's get started!
1. Understand What you are Capturing.
Stars, planets, meteors, satellites, and various celestial bodies that lie above and beyond are the subjects in the blank canvas of space. These objects lie millions of light-years away and therefore emit faint light.
The fundamental concept of astrophotography is to try and capture as much light (and therefore detail) as possible without losing quality.
2. Plan Ahead!
The most crucial yet underrated step! Astrophotography relies heavily on atmospheric conditions, hence it is wise to plan your Astro photoshoots! Here are a few guidelines to get started:
1. Check the weather and cloud cover in the location your planning to shoot.
2. Use light pollution maps to find dark skies around you. Due to artificial lighting, the urban night skies are littered with light pollution resulting in poor visibility of stars. Here are a few links to light pollution maps that can be used.
Remember:- the key is to find a location with minimal light pollution.
3. Check the lunar phases. Yes! The phase of the moon in the night sky affects the visibility of stars. When the moon is near the full moon phase, the night sky is flooded with moonlight, decreasing the contrast in the sky. During this time, faint stars and other space objects are impossible to see and capture.
The new moon sky and the nights where the moon is less than half are the best conditions to capture stars, constellations, the milky way, etc.
3. Shoot Long Exposure
Since our priority is to capture as much light as possible, we will be achieving that using the technique of 'long exposure'. Usually, clicking an image with a shutter speed longer than a second is termed long exposure.
Remembering the concept of the exposure triangle, we know that three factors that determine the amount of light sensed by the camera are Shutter Speed, Aperture, and ISO.
For astrophotography, we need to capture as much light as possible. So we need to configure the three components of the triangle accordingly. So how do we set these parameters?
Aperture: Shoot at the widest aperture possible. This enables the lens to allow as much light as possible. Depending on the lens the widest aperture can vary from f/1.8 to f/4. Aperture is the least important parameter when it comes to astrophotography (since our subject is only at infinity). Just set it to the widest possible value and you can forget about it.
Shutterspeed: The term long exposure itself implies that we shoot using a slow shutter speed. There is no correct value of shutter speed to stick by. Depending on your camera, lens, and atmospheric conditions, this value will change. Start with a speed of 5s onwards and experiment around. The objective is to capture the faint lights in the night sky. However, keep in mind not to use a very long shutter speed either as it might result in Star Trails which may be undesirable.
Star trails are a result of the rotation of the earth. This effect can sometimes be used creatively as well. To obtain a star-trailed image, some degree of post-processing is needed.
On the other hand, for a sharp image of night sky, these star trails are avoided.
The optimal shutter speed needs to be determined by experimenting with various settings to ensure that there is enough light being captured without capturing any star trails.
ISO: In astrophotography, ISO plays a vital role due to the low lighting conditions. Increasing ISO allows more light to be captured. ISO needs to be set accordingly so that the sensor is able to capture some of the faint light. However, using a high ISO number will result in excessive noise which degrades the quality of the image.
Since each camera sensor is unique, the amount of noise at various ISO numbers also varies across models. ISO 800 is a good number to start with and the number can be increased to allow more light to be captured. Take care to ensure that the digital noise does not ruin the image altogether.
The challenge of astrophotography lies in this step- Being able to experiment with the camera to capture the faint details of the night sky.
Play around with shutter speed and ISO to figure out the settings that work for you! The catch is to capture as many details as possible, without compromising its quality due to star trails and digital noise.
4. Gear needed
There are two essential pieces of equipment needed apart from the camera:
1. Tripod: Since we are using slow shutter speeds, a tripod is a must to keep the camera steady. Any basic tripod that keeps the camera stable will work just fine.
2. Remote Shutter: Even a minor camera shake due to its handling will disrupt the complete image. Therefore a remote shutter is needed. It allows you to take a picture without touching your camera. There are various models available online. These are affordable as well. However, most modern cameras now come with WiFi and Bluetooth capabilities that allow the camera to be connected and controlled via a smartphone. This is a free alternative that is convenient as well. Various manufacturers have their own mobile apps such as Canon's Camera Connect and Nikon's Snap Bridge etc.
5. To Infinity and Beyond!
The last and the easiest step to remember is that before you shoot, the camera needs to be focused on infinity. And this has to be done manually.
Some lenses have a physical indicator of the distance being focused. In case your lens lacks it then a good strategy is to point at a very distant light source (ex a street light) and set the focus.
Always ensure that the lens is focused on infinity.
The reason autofocus is unreliable is that there simply is not enough light for it to work. This is the reason why many astrophotography lenses do not even offer autofocus.
Follow these 5 steps and start your journey into this mesmerizing art. Remember, it is all about timing and patience!
Hey There! Thanks for reading till the end. Feel free to try out the various techniques I have mentioned. If you would like reviews of your images you can reach out to me on Instagram or here. You can also tag my Instagram handle @kshitij.madduri while posting your pictures for a shoutout. #photography #photographytips #learnphotography #astrophotography