In 2017 I acquired a Sony RX100 IV as a multi-purpose compact camera that I could easily carry around with me for general use. This small camera has a Zeiss f/1.8 lens (f2.8 at maximum zoom) that is equivalent to a 24-70 mm lens, has the ability to shoot in manual setting, and from the reviews appeared to produce reasonable-quality images at higher ISO values.
We first trialled the RX100's abilities for shooting the aurora during an evening of strong aurora activity on the 28th September 2017. You can see some of the images that I took with my Canon 5D III that night as a comparison. Click on one of the sections below to find the relevant information:
Although this is a much simpler and more compact camera than a full-frame DSLR, the basics of aurora photography described on my how to photograph the northern lights in Iceland still apply. This includes the requirement for a tripod to keep the camera completely still for the multi-second duration of the exposure. The RX100 has a screw mount in its base which allows it to be easily fitted to a standard quick-release plate. I mounted mine on my lightweight "travel tripod" using a basic ball head.
The settings I used for the RX100were:
Put the lens to its widest setting (i.e. fully zoomed out).
Select manual (M) mode.
For image type, select "RAW & JPEG."
Set the aperture to f/1.8 (to maximise the low light levels).
Select your desired ISO (I used 1600).
For drive mode, select "self-timer." I set this to 2 sec in order to slightly delay the camera taking a photo after manually pressing the shutter, with the aim of reducing shake and thus blur in the images. It is possible to separately purchase a shutter release for the Sony RX100 which would negate the need to use the timer.
Set focus mode to Manual Focus.
ND Filter should be set to Off.
I set both the Long Exposure NR and High ISO NR to Off. These are settings that I will experiment with in future, but for now I decided to do the noise reduction during the processing.
Set SteadyShot to Off.
Reduce the monitor brightness to avoid under-exposing your images in the field.
Set the focus. Setting the focus manually was a challenge and I wasn't 100% sure that the camera was in focus when we started taking pictures. However, the resulting images are acceptably sharp. I used the live view screen on the back of the camera and moved the focus ring until the stars (and some distant house lights) appeared to be at their sharpest. I then zoomed in on the images to check that the stars seemed to be sharp enough.
Set the shutter speed. In manual mode it is easy to adjust the shutter speed of the RX100 over the course of the night by simple use of two buttons on the back of the screen. The images below from this camera on 28 September 2017 had an exposure time that varied between 3 and 20 seconds, depending on how the brightness of the aurora varied.
Take your picture! Review and adjust settings as necessary.
We did try and shoot some real-time aurora video with the RX100 on that night, but the results were not great. To date I have not experimented further, but I will post the results here if we do try more aurora videoing with better results.
I was quite impressed with the output from this little camera. It captured some very nice aurora images and of a good quality. I could import the RAW files into Lightroom and process them exactly the same way as I do my Canon DSLR images. I would definitely recommend this little camera for someone who is perhaps looking to photograph the aurora on occasion, but also wants a camera that will be useful for a variety of other applications and comes in a handy carry around size.