This image was taken during my recent monthlong trip to New Zealand. I’ve gotten some questions on how I captured this without overexposing the obviously super bright light coming from the chalet in the foreground, so here’s how I did it. Exposure here is 30 seconds at ƒ/4.0 ISO1600 on focal length of 16mm (full frame). Image was edited on Lightroom to enhance the Milky Way in the background while tweaking the white balance a little.
This type of exposure is typically challenging as it involves two hugely differing exposure values, the superbright foreground and the faint stars in the background. To begin, I work out what’s the exposure settings needed for the Milky Way. Experience tells me I’ll be needing an ISO of 1600, at aperture ƒ/4, the maximum on the Nikkor 16-35mm FX lens that I was using, and shutter speed of about 30 seconds. Knowing fully that the foreground will over-expose, I take a test shot anyway to check my exposure for the sky. Test exposure looks good. Now, I could use a longer exposure and reduce my ISO for better quality, but it’ll mean my shutter speed is even longer, and I’ll start to see star trails. As it is, at 30s I’m seeing a little trail on the stars.
Next, I need to work out how strong is the light coming from the chalet, so I do another test shot, this time estimating the shutter to be 3 seconds while maintaining ISO and aperture settings. Still looks bright, I bring down the shutter speed down to 1 second and the exposure for foreground looks good, but now my sky is just a black canvas. All I need to do now is to figure out a way to do one second exposure for foreground, and 30 seconds for background. There are two ways that I can do this, and I’ll explain both here:
- The Hard Way: Set the camera to 30s, ISO1600 and ƒ/4. Before starting my exposure, I prepare a black card* and look through the viewfinder and place it nearly 1/3 from bottom up to check how far up I should cover the lens. Holding the black card like this, while being careful not touching the lens, I start my exposure, while gently move the card up and down a few milimeters (sort of like a vertical shake). This blocks the bright bottom part throughout the exposure, and removing the card in the last possible second (having a wired remote with timer countdown helps) exposes the chalet for about a second. The shaking motion is important so as not to create a clear black line where the card was held for most of the duration. Now you get an overall 30 seconds exposure while technically the foreground part is only exposed for 1 second.
- The Simpler Way: Set the camera to 30s, ISO1600 and ƒ/4. Before starting my exposure, I run into the chalet and switch off the light. Run (carefully) back to the camera in pitch black, and start exposing. Run back to the chalet, find the switch in pitch black, hide myself from the camera’s view, turn on the light for 1 second, turn it off, then walk back to the camera and wait for the exposure complete. What I just did is quite similar to method A as in I’m exposing the chalet light for only one second, although the method I use is different. Come to think of it it’s not that simpler than method A. Which would you have done? Give this a try next time and think of it as a problem solving challenge when you encounter such tricky scene.
*I’ve been known to use my black leather wallet before when I didn’t have a black card handy during a trip to Kyoto shooting the beautiful temples at night. Worked like a charm.