Reducing Noise With Photo Stacking

In low light situations when the ISO is cranked up to uncomfortable levels there can be quite a bit of noise introduced in the photos. If the scene is reasonable static there is a great technique for reducing the noise in the photo considerably. All you have to do is to take multiple shots of the scene with the same exposure settings and then do some magic in the after processing of the images. Let me show an example.

This is a simple scene shot in low light at ISO 5000. As can be seen there is a lot of ugly noise in the photo (both chrominance and luminance).

multi_exp_noise_raw

This is the same scene shot at ISO 5000 but with 26 RAW images stacked together. Note that no other noise reduction technique is used in this image.

multi_exp_noise_stack

Here are two 100% zoom crops from the two images at the original pixel resolution for detailed comparison.

I will do the photo stacking in Affinity Photo but it can be done in many of the photo editing programs out there.

new_stackIt is very simple to do in Affinity Photo. All you have to do is select “New Stack…” under the File menu. In the following window select all your images and click “OK”. That’s it! Note that, depending on the computer and how many images are included in the stack, this might take a while.

Since I’m shooting with a micro four-thirds system, shooting in low light situations can sometimes be tricky (with the smaller sensor size). This is definitely a technique I will use when I have the chance.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.