How to combine the night sky with a foreground landscape to making a stunning starry night photo

Combining images of our night sky with beautiful Earth-based landscapes is a rewarding experience that celebrates our place in the Universe. 

My ‘Tasman Gems’ image, the winner in the Skyscapes category of 2024’s Astronomy Photographer of the Year, captures a part of the Milky Way seen from the Southern Hemisphere that includes Orion, the Magellanic Clouds and the red Gum Nebula.

It’s roughly 180° wide and blends separate panoramas of the foreground and sky – a mosaic of nine and 31 sub-frames, respectively.

I used an astro-modified Nikon Z6, Nikon Z7 and lenses to capture my sub-frames and a star tracker for the sky panorama.

Here's how I did it.

Blend your images

To create the two start mosaics (above and below), I used the image-stitching program PTGui.

However, here I’ll focus on the steps I then took to blend them together, and some (though not all!) of my processing steps. 

I used Photoshop for the blending. Once you have your sky and foreground images, load them as layers by clicking File > Scripts > Load Files into Stack, and navigate to your files’ location.

Your images will load on top of each other in the Layers section.

The first thing you need to do is remove the sky from the foreground panorama so you can blend it seamlessly with the sky panorama.

After clicking on the foreground layer to ensure it’s selected, click Select > Sky.

You’ll see dashed lines appear between the foreground and sky.

To remove the sky from the foreground panorama, you can then apply a ‘Hide All’ mask by clicking Alt + the layer mask icon.

This leaves only the actual foreground in the foreground panorama, ready to blend with the sky image.

You can now click the ‘Move’ icon (highlighted, image below) to drag your foreground roughly into place underneath the sky panorama.

If you need to resize the foreground image at all, try Free Transform (Edit > Free Transform).

A blue box will appear around your foreground, allowing you to resize at the edges.

Sky then apply a ‘Hide All’ mask to remove the sky from your foreground. Drag your foreground into place under your sky panorama. Credit: Tom Rae" class="wp-image-175001">

Line up the layers

Because of the natural warping of panoramic images, it’s unlikely that the different foreground and night-sky panoramas you’ve created in any stitching software will align perfectly.

To perfect this alignment, use Photoshop’s Puppet Warp tool (Edit > Puppet Warp).

Applying this will put a network of gridlines over your foreground (see image below); clicking anywhere on these lines will drop pins that you can click and drag to refine your alignment with the sky panorama.

Now that the two panoramas are blended together, you’ll want to bring out the Milky Way details.

One way to do this is to reduce the visibility of individual stars, as the sheer number of stars in a Milky Way image can overwhelm the final picture.

For this image, I used RC Astro’s StarXTerminator Photoshop plug-in to reduce the prominence of the stars, allowing the fainter dust and gas details to be seen.

StarXTerminator is an automatic script, so if you’ve purchased it, you simply need to run it by clicking Filter > RC Astro > StarXTerminator.

I then chose to apply contrast and saturation to the sky panel by clicking on the sky layer and selecting Curves (Image > Adjustments > Curves).

An ’S’ curve works wonders for increasing highlights and decreasing shadows to improve overall contrast.

You can create this shape by clicking and dragging the curve using your cursor (highlighted, image below). 

To calibrate the colour of the foreground, I re-selected the foreground layer and made many small adjustments to hue and saturation, colour balance and white balance (all found in Image > Adjustments) to reduce the contrast between foreground and sky, and create a natural look. 

Once your foreground is processed, you can complete the image by making overall adjustments to both the foreground and sky.

Using the Camera Raw filter (click Filter > Camera Raw Filter), you can add a final ‘pop’ to the image, increasing the clarity, detail and colour sliders gently until you have the desired effect.

‘Tasman Gems’ came to 400 megapixels and it required almost 130 Photoshop layers of small adjustments to create this in-depth look at New Zealand’s summer night sky.

3 quick tips

1. Use Curves to create a brighter sky around the horizon for more contrast with the foreground.
2. After using the Puppet Warp pins, be sure to crop out any overstretched or warped details from the image.
3. Layer masks are crucial. Get familiar with selectively applying and modifying them.

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