Banish Noise

Use high ISO with impunity!

The topic of high ISO noise came up at the “refresh reception” of the PCPC Gallery on October 17, 2020. The discussion was about my entry “Dancing at the Festival“. Later that evening I updated to the latest version of Topaz Labs DeNoise AI . That is an amazing tool and it has helped me with my low light and high ISO photos for quite some time. That made me decide to share a demonstration of what can be done.

That photo, Dancing at the Festival, was taken at the evening concert of the first day of the Peachtree Corners Festival in 2016. The time was around 8:20 pm, just a quarter hour before official sunset, but the trees surrounding the festival stage area had already brought an end to sunshine.

The music was playing and the audience got into the spirit. A number of people were dancing in front of the stage. When they saw me they began to mug for the camera. A lady with the two girls began dancing, which provided my photo. Two shy girls came up and also started posing for the camera. I must have just started to adjust my camera settings for another subject, because the resulting photos were very underexposed.

I was using my Nikon D800 with a Nikkor 24-120mm f/4G lens, my favorite for this kind of shooting. I like to use aperture-preferred mode and used a setting of f/8. That gave me enough depth of field at the long end (about half a foot at six or seven feet from a subject). At the other end of the zoom range, 24 mm, the hyperfocal distance is 8 feet, that means everything from 4 feet to infinity is sharp – no worry about focusing.

I like to set the slowest shutter speed to 1/125 second, and allow auto-ISO so the camera selects the ISO sensitivity. Back in those days I would limit the highest ISO to 6400 as the noise at that setting was all I felt I could tolerate. For reasons I don’t recall the shutter speed for the photo of the two girls was 1/400 sec, hence the bad underexposure in the fading daylight.

Last night I used the latest version of DeNoise. First I converted the image from the RAW file to JPG. I use ON1 Photo RAW 2020 for that as it has a very nice HDR effect tool that brings the shadows up nicely, applies detail contrast and makes the resulting image more natural looking that a straight conversion. Of course, I also has to use the exposure slider to lighten the image. Bringing up the shadows also makes noise on those areas very prominent.

The result was a pleasant photo, but unusable do to excessive noise. Here it is:

As you see it here it might not look too bad. But if you inspect it carefully you’d agree, nope, not usable.

This is where Topaz Labs DeNoise AI comes in. Here is what that app shows:

This is using the “Low Light” mode and the default settings. As you can see in the app, the original on the left, and the corrected image on the right, this tool removes the noise beautifully.

Here are crops from the original and the denoised version:

Notice the eye lashes, the detail in the hair. And, of course, the skin. Fun fact: The noisy original is 43.6 MB, the cleaned up version is 28.3 MB. The difference is noise, 15.3 megabytes of it!

Here is a cropped version of the cleaned up image:

Look at those beautiful little girls, look at the embroidery, look at the eyes. Now this photo does them justice.

Ludwig


Postscript

Here is how the photo shows in Nikon ViewNX-i. The red rectangle shows where I focused. Notice that I missed badly. Nowhere near the eyes. Too much in a hurry. My eyesight at night is pretty bad, being an octogenarian has its downsides. That is why I need the depth of field. The focus distance was 7.77 ft with the DOF ranging from 7.23 – 8.39 ft,