Astrophotography using Smartphones

               Astrophotography is a fascinating combination of art and science that involves capturing stunning images of the night sky and celestial objects. Many people believe that astrophotography requires expensive and complicated equipment, such as telescopes, cameras, and filters. However, with just a smartphone and a few simple accessories, anyone can capture beautiful photos of the stars, planets and even the Milky Way. In this article, we will show you how to get started with astrophotography using smartphones. We will discuss what you need to prepare, how to set up your camera. By following these steps, you will be able to impress your friends and family with your amazing images of the night sky.

  To get started with astrophotography, you need a smartphone. It's better if you have an Android phone because they have a dedicated Professional mode in their camera application. Open your camera app and go to Pro mode; it's probably in the more section.

The most important settings that you should be able to change in Pro mode are the Shutter Speed and ISO. While most phones can adjust their ISO, some cannot adjust the shutter speed, so be aware of that. Shutter speed is the number of times the shutter is closed or a photo is captured in a unit time. While most phones refer to this feature as the shutter speed, the scale used to adjust the feature is calibrated in terms of shutter time, which is the time in seconds that the shutter stays open for one photo. When capturing distant objects like stars, you need the maximum amount of light possible to form a detailed image. As the number of rays that can enter the camera lens is extremely low, you can increase the shutter time to gather more light. However, there is a catch to increasing the shutter time as much as possible. As the earth rotates around its own axis, the stars appear to move in the opposite direction. When the shutter time is too high, the stars would be slightly shifted relative to their original position, forming star trails. However, as the maximum shutter time most phones can reach is 30 seconds, these star trails would not be pretty looking. Instead, they will cause photos to look blurry.

In my experience, 16 seconds has been the sweet spot to capture the highest amount of light without resulting in a blurry image. If 16 seconds is not an option, put it to 20 seconds.

Next up is the ISO, which is the camera sensor's sensitivity to light. Higher numbers mean that the end photos will have more light, but with smartphone cameras, there is more to consider. Smartphone cameras heavily rely on post-processing to capture good photos to counteract the fact that smartphone camera sensors are really small. When the ISO is increased too much, a lot of noise appears as the processor doesn't have enough details to fill those pixels. Most phones allow you to manually adjust the ISO between around 50 to 3200. Higher numbers over that might be useless because of the noise issue, as 3200 is already is at night. If you need to capture stars or planets like Jupiter or Saturn that we can see by our naked eye, I find that 800 is a good value. If you are going to capture something like the Milky Way, 1600 would be good, higher might result in more details but also a lot of noise.

Focusing is not that important because most phones today have really good auto-focusing, but if photos are ending up blurred, point the phone at a bright star that is visible in the viewfinder of the camera. Now go to manual focusing and drag the slider to infinity and slowly drag down again and stop at the point where the star appears the smallest. That's when the camera is focused.

To keep your phone steady during the 16-second exposure time, you'll need a tripod or some other stable surface. Once you have set up your phone, go to the camera settings and look for the option to enable Raw copies. If it's available, turn it on. Then, set the settings as described above and add a two-second timer delay to avoid any shaking caused by pressing the shutter button. Finally, press the shutter button and wait for the phone to capture the image.

After capturing the photo, you'll need to edit it. Editing is a crucial aspect of astrophotography, and photographers often spend hours or even days editing their astro photos. That's why taking Raw copies can be so beneficial - they offer more flexibility during editing.

Keep in mind that there is much more to astrophotography than what I've covered here. This is just the basics to get you started, and I will cover more in a later article. With practice and patience, you can capture stunning images of the night sky with your phone.