I keep on seeing the advertisements about software for reducing noise in digital photos. It gives the idea noise is always a huge problem that needs to be addressed. This is advertising, of course. Or is it indeed an issue that we have to solve with specialized software?.
This is not a rant against the software companies that sell programs specifically for noise reduction. It’s something I became curious about after I read a somewhat older article about limiting the ISO setting to a maximum of ISO 400 to prevent noise. With noise reduction, is the end result better or worse compared to the original? Is it always necessary to perform some sort of aggressive noise reduction to make the images worth showing? I can hardly believe that.
A Bit of History
I started photographing in the early years of the nineties. I used a lot of high ASA film for my concert photography. ISO was called ASA back then. Often, the films I used were limited to 400 ASA (ISO 400), but I exposed these films as 1,600 ASA. In other words, the images were two stops underexposed. It needed a forced development of the film to correct this, resulting in a lot of grain or noise, if you will.
Photos with a lot of grain were often considered artistic, moody, or on some occasions, special. I don’t say my images could be considered as such, but a lot of photographers used this exposure technique to increase the amount of grain on purpose. But with the age of digital photography, it has suddenly become a big problem.
The grainy structure of film and digital noise are two different things. In the first era of digital photography, the noise was indeed ugly. It was noise at its worst, and there was no similarity with the grainy structure of film whatsoever. But the structure of the noise has become more film-like. It’s more natural than ever, although it does depend on the camera you’re using.
I never worried too much about the ISO setting of my digital camera. If I needed to shoot at ISO 1,600, I did. Of course, there was a limit on how high the ISO could be set without ending up with only noise and no image at all. But the limit has pushed forward ever since.
Back then, my Canon EOS 20D could do ISO 1,600 but not much more. Now, my Canon EOS R5 can do ISO 6,400 with less noise, and even ISO 12,800 is acceptable for me. On top of that, the noise structure feels more natural.
How I Look at My Images
If I look at my photos that are shot with high ISO settings, I do see noise. For some concerts, I used up to ISO 12,800, and that’s also the case for night sky photography. I even tried ISO 32,000 for the Milky Way with my Canon 5D Mark IV with nice results. Although, I must admit, I used stacking to reduce the noise and preserve details.
When viewed at a 100% magnification, the noise levels become apparent. But who looks at an image like that in real life? If I look at an image, I want to view it as a whole from a proper distance. This way, the noise isn’t that visible anymore, even when the image is shot with extremely high-ISO levels.
I printed a book celebrating my 10 years of star trail photography in 2017. Some of the featured images were shot at ISO 6,400. Even though the print size was a nice 30 cm on the longest side, the noise wasn't a problem at all. Of course, if you look at the images inside the book at a very close distance, noise can be seen. But then, it's like looking at an image through a magnifying glass.
My book, Winter at Lofoten, had a lot of night images featuring northern lights taken at high ISO levels. Canon Netherlands printed one of my Perseïds meteor shower images at 30x40 cm with a professional printer. The noise never became obvious, even though the image was at ISO 6,400 on a Canon EOS 5D mark III. But when viewed at 100% on a computer screen, the noise was clearly there.
The wedding albums I make for my customers often have photos that are shot at high ISO levels. The images inside the albums do look perfect, and no noise is visible. So, why would I need any additional noise reduction software?
A Bit About Exposure and Processing
Perhaps I need to explain how I treat my images regarding post-processing. I use Lightroom Classic for the most part. First of all, I always try to use exposure to the right (ETTR), even with my night sky photography. This way I can avoid extreme recovery of the shadows and blacks in the images, which often results in an increase of noise. I use a mask for sharpening to avoid the effect on the parts that don’t need sharpening. This also prevents an increase of noise. If necessary, I set the noise reduction in Lightroom Classic to 25 or so, almost never higher. And that’s it.
Is Noise a Taboo?
Yes, I do see noise when I look at some of my photos on my computer monitor, but I know it won’t become obvious in print. If I use an image for social media or on photo-sharing sites, the resolution is reduced to web dimensions. Any noise is lost in the process and won’t be visible anymore.
Do we need noise reduction because we love to scrutinize our images at 100% magnification? Or is it because we are only trying to produce smooth and noiseless images because we believe that’s how it’s supposed to be?
On most occasions, I believe we don’t need noise reduction software at all. For online use, the noise is already invisible because of the downscaling. For prints, it is often lost in the print resolution and through a proper viewing distance. I would advise everyone to be careful when considering using this kind of software.
What do you think about noise reduction? Is it necessary for your photography, and if so, can you explain why? It’s something I would love to understand. I’m looking forward to your comments below.