Night photography has challenges. When you add sky, challenges multiply.
Have you ever gotten back from a Milky Way shoot and found that your star focus just wasn’t quite there? I have. While there are tricks and techniques you can use involving daytime focus and taping down your focus, Olympus has a different autofocus mode that makes things even easier.
Focusing on the stars with Starry Sky AF
A focus mode called Starry Sky AF is available on the new OM-D E-M1 Mark III. If you have clear skies and stars you activate the Starry Sky AF mode, the camera focuses on the stars with ease.
It takes about 12 seconds for the camera to scan the sky for the brightest points. I recommend that you set your focus points to a large grid. If you have a single focus point set the camera has a more difficult time finding focus.
With Starry Sky AF, you acquire focus using back button focusing (with the AEL/AFL button). Once focus has been determined, you’ll save the focus acquisition time in subsequent shots.
If you use the shutter half button focus, each time you make an exposure you’ll have to wait for Starry Sky AF to do it’s thing. It doesn’t lock your focus. Another reason for using back button focus would be if there is some cloud cover or haze in your field of view, Starry Sky AF may not acquire focus. You can pivot the camera to a clearer sky view and get your focus then recompose the shot.
Adding in Live Composite
Starry Sky AF can be combined with the Live Composite feature for creating images with star trails. Live Composite will make multiple exposures of the scene on the same frame. The beauty is it will only add additional light and allow the shadow areas to remain as they were on the first exposure.
Available when you have Bulb selection on the mode dial (“B”), make an exposure using manual or aperture priority with which you are happy. Use those settings to give you the correct density for your shadow areas. Enter those settings in the Live Composite menu, then push down the shutter button.
The camera will prepare itself by scanning the scene. It will then allow you to begin the exposure. Press the shutter again to start the actual exposure. Watch on the progress on the LCD screen. When your star trails are the length you like, end the exposure by clicking the shutter button. The camera will then complete the process doing a noise reduction.
Making this image
The base exposure for this capture was 25 seconds. The camera repeated the same exposure 70 times while only adding the extra light. Each complete exposure showed the results on the LCD — the total exposure time was approximately 29 minutes.
An additional 25 seconds was taken making the noise reduction. I was extremely pleased with the lack of noise in the finished file as I was shooting with ISO 1600. A full moon provided the wonderful lighting on the red rocks.
Additional uses for Live Composite
Live Composite can also be used for lightning strikes, fireworks and car light trails. Seeing the results appear on your camera back is pretty magical. You can check other features including Starry Sky AF & Live Composite, along with other Olympus OM-D E-M1 Mark III features in this article by Bryan Esler.
Yours in Creative Photography, Bob