Comparison of Noise Reduction Tools

Recently I tested a 16mm extension tube on my Olympus M.Zuiko Digital ED 75mm f1.8 lens. I wanted to verify the combination could be used for impromptu macro work, thereby limiting the the number of lenses and the weight of my camera bag on trips. This rig works, but restrictions include inability to alter the extremely shallow depth of field, and focus only by changing the camera-to-subject distance. Here's a JPEG from the original noisy raw test file shot at high ISO.

75mm lens with 16mm extension tube

When I used one of the new noise reduction apps on this file, the results were extremely disappointing. That led to this "eyeball" comparison of four non-Adobe products for cleaning up noise in digital images. Here's my ranking of the four products.

Fourth: ON1 NoNoise AI

ON1 NoNoise AI out-of-the-box setting

ON1 released their artificial intelligence noise reduction application several months ago as a standalone product. It is scheduled to become part of the non-destructive processing workflow in ON1 Photo RAW 2022 when the new version of Photo RAW is released in a few days.

Note all of the grainy noise in the shadow area in this auto correction from the app, which could not be corrected with the available adjustments. When the app was announced, ON1 heralded this as the best noise reduction available. Based on my observation, ON1 NoNoise AI is not there yet.

Third: DxO PureRAW

DxO PureRAW from its automatic processing

This year DxO borrowed some of their technologies from PhotoLab and introduced PureRAW, a demosiacing algorithm and denoiser designed to streamline digital darkroom workflow for busy photographers. Everything is automatic. The user can make no adjustments to this process. Unfortunately, the app oversharpens images, at least according to numerous complaints published on the DxO forum. 

In this test image, grainy noise is still present in the shadow areas. I expect an update, giving the user some control over processing in this app.

Second: Topaz Labs DeNoise AI

Topaz Labs DeNoise AI with its Standard setting

Topaz Labs has always been among the third-party leaders in digital image noise reduction. Their AI product provides a choice of four algorithms for noise removal, and previews can be viewed before making a commitment. An excellent app, but slow.

In this test image, Topaz Labs has removed virtually all of the noise, but there seems to be a few splotchy areas remaining in the shadows. A different algorithm choice or adjustment could have eliminated this.

First -- DxO PhotoLab 4

DxO PhotoLab 4 with DeepPRIME selection

DxO PhotoLab's noise reduction remains the gold standard by which all other similar products are judged. The user has an option of noise-removal settings, depending on the severity of the noise. The only downside is the slow speed of the processing.

In this test image PhotoLab has removed all of the noise with no negative impact on image detail. With no doubt, the best noise removal tool available.