Nightscape photography can certainly be a challenging form of photography and knowing your equipment and how to capture light can certainly benefit the quality of your photograph.
So why do we want to stack our nightscape photographs, well the answer is simple! By stacking our photographs we end up with a final result that is much cleaner to look at and more detailed.
When we shoot the night sky it's important to try and get the best exposure in camera rather than ramping up any kind of exposure setting during post processing, the problem with this is we often find ourselves cranking up our ISO if our aperture is wide open and our exposure is maxed out!
So what happens when we photograph with higher ISO, well we start to introduce a thing called noise into our image but not only do we increase the amount of camera noise in our photograph but we reduce the dynamic range / tones of our photograph.
This is where stacking can play a big part in increasing the signal to noise ratio, increasing the dynamic range which all equates to a nice clean photograph that we can print and display in all it's glory!
Stacking nightscape photographs used to be extremely difficult and time consuming, it used to take me an hour to stack a few images making sure stars are all manually aligned and the foreground is also aligned. Thankfully there is a piece of free software out there called Sequator.....my lifesaver!!!
Sequator can stack a nightscape image of 5 photographs for me in just under 20 seconds and it does a fantastic job too!
Below is a single photograph taken with a Nikon Z7, ISO 10,000 with a Nikon 50mm F1.8s lens at F/1.8, you can clearly see how much noise is in the photo.
Now lets have a look at the same photograph, same settings with 5 images stacked.