An Astro Experiment

Have you ever seen something you wished you could photograph, but feared you didn’t have a suitable camera? What about a photo of the stars at night, and all you have with you is your phone? Cameras in smartphones have greatly improved in recent years, and have wonderful new features. One of these is the ability to make images in low light and, yes, even of the stars at night! The featured image for this post was taken with my phone, a Google Pixel 3. Google is up to Pixel 5a, so my phone is a few years old. In fact, I think I’ve even paid for it by now!

When I read about how to use my smartphone to photograph the stars, I just had to try it. The results were surprising. That led me to consider a little experiment. On Monday, September 13, I set up in the driveway to do a comparison. What sort of results could I get with my phone, my infrared converted Olympus camera, and my regular Olympus camera? Let’s begin with the phone.

In the first image, looking northwest, you can actually see the Andromeda Galaxy. It’s the bright blob a little above and to the left of the center of the image. Of course it doesn’t look like an image from the Hubble telescope, but it is Andromeda, nonetheless. (Take a couple of minutes to watch the video.) The second image is a look straight overhead. Do you see the Milky Way? I was really surprised that a phone camera could reveal that. Looking up means looking through as little atmosphere and light pollution as possible. So I decided to put the phone to a real test–looking south. Lots of light pollution and haze there, but with some processing in LightRoom, you can see the Milky Way in the third image.

OK, so how do you do this? First of all, do not try this simply hand-holding your phone. You need to mount it on a tripod (there are products made for that purpose) or somehow get it to be steady by laying it on a rock or the ground. Anything so that it doesn’t move. Then, for an Android phone, set the camera for Night Sight. I’m sure there’s a similar setting for iPhones. Once you’ve got the phone resting steadily and you’ve set up the camera, press the shutter button. First the phone will go through a process of automatically focusing on the stars so they look like little pin-points of light. Then the camera will begin layering images on top of each other for about a minute. With this process it builds up light points without overexposing the background. Notice that this works best with as little light pollution as possible. For example, the overhead image is much better than the south-facing image. Give it a try! You may be surprised. I surely was.

Having noticed the haze in the south, I decided to compare my infrared converted (720nm) Olympus OM-D E-M5 mark ii camera with my regular Olympus OM-D E-M1 mark iii. I had noticed previously that the infrared camera seems to cut through light pollution better than the un-adapted camera. In both cases I simply pointed south and used the same lens, the M.Zuiko 12mm f/2.0. You can see the results in the next two images. On the left is the infrared image, on the right the regular image.

Some things to notice about these images. First, the infrared image is not perfectly in focus. I need to practice focusing more with that camera, I guess. But, notice that you can see the Milky Way better in that image than in the other one, or even in the phone image. The infrared camera can cut through haze and light pollution better than an un-adapted camera. While the un-adapted camera does not pick up the Milky Way as well, the stars are tack sharp. This is because of the Starry Sky Autofocus function the E-M1 mark iii camera employs. I must say, that is quite a sales point for me! One of the most difficult steps in astrophotography is getting the focus correct.

I hope you enjoyed this post. Stay tuned for more experimentation with the phone and the infrared camera.