Prasun's Uluru - a double-stacked astroterrestrial photo

I've shown astroterrestrial photos before, photos with a subject on the ground with a night sky background. Here's a stunning example. It's Uluru (obviously) from the viewing area with the South Eastern sky behind it.

The photo was taken by Prasun Agrawal a little while back, and I was knocked out by its quality. I love the hook shape of the Rho Ophiuchi cloud complex near Antares.

But there's more to the image than than this. You can easily see details in the rock, such as Kantju Gorge on the mid-left, that interesting line of circular features in the centre of the rock, and bushes in the foreground. It's an unusually high level of quality.

How did Prasun do it?

It's a composite: a common way of producing this type of image. Single images are more challenging as you need to focus separately on foreground and background.

With a composite, you take a single foreground image and combine this with a "stacked" image of the sky. The stacking process uses many "subexposures" for a clean, low-noise image. You then manipulate foreground and the background separately to get the lighting you want.

But Prasun has gone a step further here, and taken a foreground stack of 10 subexposures, each 1.5 seconds long. This produced beautiful, low-noise detail on the ground.

Prasun uses a program called Starry Landscape Stacker for a Mac, and used masks to combine the foreground and background. Getting the interface between the images is a challenge, as the Earth's rotation meant that on the horizon there were few images to stack.

Because the camera is pointing towards the East, the stars were rising there, and Prasun was able to position the final stack where the first image appeared, and mask off those that rose afterwards. That way, the stars right on the horizon benefited from the full stacking process.

It's complicated, but using these techniques, Prasun has generated wonderful detail not only in the sky, but also on the ground. Congratulations on such a fantastic image!