DxO PureRAW 4 promises to “supercharge your cameras and lenses” by offering a suite of image quality corrections for RAW files: deep-learning noise reduction, superior demosaicing, as well as per-lens correction of distortion, softness, vignetting, and aberrations.
At a separate purchase of $119, or an upgrade price of $79 for existing users, it really has to prove its worth over the competition. In this review, I’ll show the results from testing PureRaw 4 against PureRAW 3, as well as leading alternatives from ON1, Topaz, and Adobe.
PureRAW is somewhat unique among the suite of products I’ll be testing, as it offers more image quality improvements than just noise reduction. The closest competitor is probably Lightroom’s Enhance features, which enable both better noise reduction and demosaicing compared to Lightroom’s regular workflow. Both Topaz and ON1’s products offer some degree of detail enhancement and sharpening, but these are a far cry from DXO’s implementation.
As such, I’ll be mainly considering noise reduction performance for these tests — but don’t forget DxO’s other features when evaluating these offerings. Those shooting with fast primes, ultra-wide angle lenses, or modern designs that de-prioritize vignetting or distortion would all benefit from these features.
What’s New in PureRaw 4?
Compared to PureRAW 3, PureRAW 4 offers DxO’s next-generation algorithm for noise reduction: DeepPRIME XD2. According to DxO, this is trained on billions of images, offering enhanced clarity and detail. In my past testing, DeepPRIME XD was already transformational for high ISO images, so I’ll be excited to see how this performs. Along with the new algorithm, new sliders have been added to enable refined controls of noise reduction.
PureRAW4 has also updated the way it handles sharpening. DxO has lab testing for a huge array of lenses and uses that info to selectively sharpen the image by different amounts across the frame. This targeted sharpening approach is theoretically much better than a global sharpening value or even a per-lens sharpening value, like what you would get by default in Lightroom.
DxO has also made some workflow upgrades in PureRAW4, including an automated widget to import and process raw files. Other changes have been made to output formats, processing previews, and batch naming.
Speaking of workflow, DxO makes things pretty easy. PureRAW 4 can function as a standalone program, allowing you to import raw images, enhance them, and export either DNG, TIFF, or JPGs. Alternatively, you can invoke PureRAW 4 via Lightroom’s export menu, with the processed files being automatically re-imported to your catalog. Overall, it’s very easy to use and should integrate into any workflow.
Performance Versus the Competition
For testing, I compared a variety of RAW files from a range of cameras. Tested models included recent mirrorless models, like the Sony a7R V and Nikon Z7 and Z9, as well as older DSLRs like the D810. I also tested results from drones, including the Mavic 3 and Mini 3.
All software tools were tested at their default values. I found that tweaking the sliders offered negligible improvements for the time invested – these tools are really all about the algorithm powering them, unlike older implementations of noise reduction in Adobe Camera Raw or Photoshop.
The listed times taken are for the tools to bulk process 15 RAW files from a mix of cameras on a Windows system with a 5950x, 64GB of RAM, and an RTX4080. Files were read and written to an NVMe SSD. PureRAW 4 was a beta version close to release, while all other software was the most recent version at the time of publishing.
PureRAW 4
PureRAW 4 offers a range of controls for tweaking just what improvements you want to make to your image. You can select to just denoise, correct optical issues, or some combination of those settings. While the optical corrections and sharpening don’t impact noise reduction performance directly, sharpening can improve the final look of an image after noise reduction.
PureRAW 4 offers two algorithms by default: DeepPRIME and DeepPRIME XD2. These aren’t two intensities of noise reduction, but instead a computationally “cheaper” and “more expensive” process. DeepPRIME takes less time to process, but won’t yield the full quality that XD2 is capable of. If you’re already taking the time to bring the images into this tool, spend the extra minute or two of processing time to get the best results.
Photographers with bulk processing needs, like events or sports photographers, may still need the time savings available with regular DeepPRIME however. Even more time can be saved by re-enabling the legacy High Quality and Prime algorithms, although these will be significantly less effective at actually reducing noise.
For the full set of test images, PureRAW 4 took 1:14 for DeepPRIME, 1:23 for XD2, and 1:44 for XD2 with optical corrections.
The results of my testing were quite clear: PureRAW 4 offered the best results across all the test files. Color, contrast, sharpness, noise reduction, and fidelity to the original RAW file were all excellent. Processing times were also quite reasonable, with this software making the best use of my hardware in terms of utilization. The finished images were significantly cleaner in terms of both luminance and color noise, but without any AI-style artifacting that could be observed in some other tools. Using the full set of corrections, including optical corrections, yielded a great-looking file right out of the tool, with enhanced but not overdone sharpening.
Drone photographers, as well as photographers with lenses that “force” lens corrections, may also be interested in using PureRAW as a way to control which corrections are actually applied to their image.
PureRaw 3
PureRaw 3 was previously my go-to option for noise reduction. In testing, I found it offered wonderful results for both mid and high-ISO files, and the custom lens corrections were particularly helpful for some of my favorite lenses, like the Nikon Z 14-30mm. I didn’t really know if it could be improved upon, but DxO succeeded in making PureRaw 4 significantly better.
Purely judged on noise reduction, PureRAW 3 was quite close in performance, but PureRAW 4 did eke out a small win when evaluated at 1:1. PureRAW 4 did even better when considering the total set of enhancements. Sharpening and chromatic aberration reductions were handled even better in PureRAW4.
The most immediate difference I noticed when swapping back to PureRAW 3 was how it was significantly slower. The image quality improvement has always been worth it for select images, but PureRAW 3 was among the slowest in testing. With this set of images, it ranged from between 2:48 for basic Prime noise reduction, up to 3:46 for PrimeXD with optical corrections. For comparison, PureRAW 4 clocked in at 1:44 for PrimeXD2 with optical corrections, essentially processing files twice as fast.
This speedup didn’t result in any loss of performance, however. PureRAW 3 files were already quite clean, but PureRAW 4 still improved the handling of shadow areas in high ISO files in half the time.
These two definitely are the closest in final image quality, however, so PureRAW 3 users should primarily look to the significant workflow enhancements as justification for upgrading.
Lightroom
Lightroom offers two noise reduction approaches: the default Adobe Camera RAW method and the more recent “Enhance” method.
The default method has a few advantages: it’s basically instant, requires generating no separate file, and is included by default in Lightroom. However, as expected, it offered by far the weakest performance. Since it essentially just blurs or desaturates to reduce luminance or color noise, higher values drastically reduce detail and fidelity. It’s a good baseline and is fine for low-ISO images, but newer tools can do far better for high-ISO images.
Enhance is Adobe’s take on these AI image quality enhancing tools. Built into Lightroom, Enhance offers the option to improve RAW details via better demosaicing, reduction of noise, or intelligently upscaling. After processing, you’re left with a new DNG file that preserves all the adjustability of your original raw file, but with better image quality.
Enhance took 3:38 seconds to process the batch set of test files and it was easy to use. Finished files were automatically stacked with the originals in Lightroom, making file management easy for users who are already cataloging with it.
On mid-range ISO photos, Enhance yielded similar levels of noise reduction to PureRaw 4. With optical corrections turned on, however, PureRaw 4 pulled ahead by sharpening more without generating halos or artifacting. Also, compared to Lightroom, PureRAW 4 required no user skill or input to achieve good sharpening. It also handled chromatic aberrations slightly better.
At higher ISOs, PureRaw 4 did significantly better with both noise reduction and handling of colors. This is particularly noticeable around ISO 3200 to 6400 on modern bodies, as Enhance Details falls behind PureRaw and never recovers.
Topaz DeNoise AI
Topaz DeNoise AI was quite fast at 1:22 for the set of test images, but offered mediocre results. Mid-range ISO results were comparable to Enhance Details in Lightroom, but high ISO images were unimpressive. High ISO images looked splotchy, with a loss of color and detail compared to DxO’s versions. Even compared to Enhance, Topaz lost visible detail, although the images did end up with less visible noise.
Additionally, Topaz seemed to introduce artifacting, both in areas of smooth texture as well as when handling small details like text. In the sample image, note the artifacting on the wall and in the poster.
Given the separate purchase required, I’d be hesitant to recommend Topaz’s product unless you’re already using its PhotoAI suite and have “free” access to the tool. It may also have a niche for users who need to process a bulk amount of images, as it is faster than Lightroom’s Enhance feature.
ON1 NoNoise AI 2023
NoNoise AI from ON1 offered poor performance with my test images. While it wasn’t particularly slow at 2:15, it yielded worse results than other options, even compared to Lightroom’s basic ACR-style noise reduction
High ISO images were particularly difficult for NoNoise, with my starlight-style test image revealing severe artifacting — it almost looked like an oil painting filter, rather than a noise reduction algorithm. On mid-ISO images, it did an OK job reducing luminance noise but never handled color noise well.
Overall, I didn’t see a single test image where it offered a meaningful win over Lightroom processing, making the $49 to $69 purchase a tough pill to swallow. ON1 fans or photographers who don’t use another editing tool may want to look at the new version coming out in 2024 – at the time of publishing this was unavailable for test and it may yield better results.
Should You Buy DxO PureRAW 4?
If you shoot at high ISOs or want the best results from your lenses, DxO PureRAW 4 is an easy recommendation for new users. Building on the already-great image quality of PureRAW 3, PureRAW 4 bested the competition across images from mirrorless, DSLRs, and drones; as well as across a range of ISOs. It’s also great for more than just noise reduction, as it also offers powerful optical corrections and easy sharpening.
Available for $119, PureRAW 4 offers some of the best value for image quality improvements in software. I also really appreciate the option for a single purchase, rather than the increasingly common subscription model.
The only users who may want to give it some extra thought are PureRAW 3 users. While DxO offers a slight discount for upgrade licenses at $79, the improvements from version 3 to version 4 are primarily limited to better sharpening and faster processing. If you’re a casual user or mostly use PureRAW for noise reduction, consider whether those improvements are worth $80.