Low Light, High Noise and ISO Invariance

Hi Folks:

It was a dark and stormy night. I’ve always wanted to write that… haven’t you? Okay, in this case it wasn’t night (mid-to-late afternoon) and it was sunny rather than stormy, but it was dark. Marcia and I were on a trip to Tofino, BC and I was wandering along the boardwalk of the Rainforest Trail in the Pacific Rim National Park Reserve. The elder trees soaring above me blocked out much of the daylight, but they were the reason I was there.

Before we get too far, a few basics to get out of the way. First, I was shooting with a Sony a7Riii camera with the FE 24-105 lens, set to 1/125th second and f/6.3. ISO was set to 5000, but we’ll get to that later. I didn’t bring a tripod that day, but I did have my camera sitting on a Manfrotto monopod. Second, I have no idea what you see when you look at these images. This is partly because I don’t know if your monitor has been calibrated and profiled, and partly because I don’t know if you’re using a web browser that allows colour management and/or if you’ve enabled that. In the end none of that really matters because this is essentially an apples to apples comparison. I should note that this post isn’t targeted toward beginner photographers, but if you read something you don’t understand, please feel free to leave a comment on this post or fill in our Contact Form. The only stupid question is the unasked one.

There are three software packages in this game: Capture One 23 (16.1) is my raw editor. PTGui 12.20 is software for stitching panoramas, and Topaz DeNoise AI 3.7.2 is noise reduction software. AI is a term used ubiquitously these days, but the only intelligence involved here is still with the programmers. AI software uses very large databases of information and certain algorithms to make what one might call educated guesses as to what the user wants. Also, when processing in any of these packages there are what are known as auto adjustments (I’ll refer to them here as AA) and there are also sliders whereby one can tweak the suggested settings. With the exception of the final image, I stuck to AA in order to keep the processing as equivalent as possible.

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