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DxO today intro­duced the new ver­sion of their RAW proces­sor Pur­eRAW 3*. I already had the oppor­tu­ni­ty to test a beta ver­sion of it in detail pre­vi­ous­ly and would like to share my impres­sions here.

What’s new?

Com­pared to the pre­vi­ous ver­sion, Pur­eRAW 2, DxO has sig­nif­i­cant­ly and rea­son­ably expand­ed the range of pro­cess­ing options. In par­tic­u­lar, I appre­ci­ate the pos­si­bil­i­ty now of hav­ing con­trol over the sharp­en­ing, which in my opin­ion was often too intense in the pre­vi­ous version.

Besides some oth­er visu­al changes to the appear­ance, which I like bet­ter so far, the main new fea­ture is that DxO Pur­eRAW now also sup­ports the new AI-based Deep­PRIME XD algo­rithm. This algo­rithm was first intro­duced in DxO’s pow­er­ful image edi­tor DxO Pho­to­lab 6 Elite (my full review of it can be found here) and has now final­ly found its way into the updat­ed ver­sion 3 of PureRAW.

PureRAW vs PhotoLab difference

Unlike the full-fea­tured Pho­to­Lab image edi­tor, Pur­eRAW is reduced to the actu­al devel­op­ment of RAW files, which it out­puts either as lin­ear RAW files in DNG for­mat or also as TIFF (in up to 16bit) or JPG files. Pur­eRAW only per­forms demo­saic­ing, denois­ing and opti­cal cor­rec­tions using spe­cif­ic cam­era and lens mod­ules cre­at­ed by DxO.

The final pro­cess­ing of the images, such as expo­sure adjust­ments or crop­ping is not imple­ment­ed in Pur­eRAW. This requires addi­tion­al soft­ware. The most ele­gant way to do this is to work with Adobe Light­room Clas­sic or Pho­to­shop. DxO Pur­eRAW pro­vides inter­faces for both pro­grams, which results in a very smooth workflow.

Denoising with DeepPRIME (XD)

In my opin­ion, the absolute­ly out­stand­ing fea­ture of both Pur­eRAW and Pho­to­Lab is the qual­i­ty of noise reduc­tion of high-ISO pho­tos with the Deep­PRIME algorithms.

If you, like me, still know the lim­i­ta­tions of ana­log pho­tog­ra­phy, you’ll be amazed by the results that can be achieved with cur­rent dig­i­tal cam­eras, even in low light.

In ana­log pho­tog­ra­phy, sig­nif­i­cant image noise was already vis­i­ble at ISO 400 in col­or and ISO 1,600 in black-and-white. Today, cur­rent dig­i­tal cam­eras can han­dle this with­out any prob­lems. Nev­er­the­less, DxO shows that even more is possible.

The secret is the AI

The secret behind DxO’s improved algo­rithms is arti­fi­cial intel­li­gence. At the lat­est since Chat­G­PT, AI has been on everyone’s lips. Here, DxO’s tech­nol­o­gy was used specif­i­cal­ly to reduce noise in dig­i­tal images. By com­par­ing bil­lions of noisy RAW files as input with cleaned exam­ples as out­put, a mul­ti-lay­ered neur­al net­work was trained. A spe­cial fea­ture is that Deep­PRIME already works with the raw data of the cam­era sen­sor before the debay­er algo­rithm (more infor­ma­tion about Bay­er sen­sors can be found here) and there­fore has much more detailed image infor­ma­tion avail­able than oth­er con­vert­ers that start afterwards.

What is DeepPRIME (XD) able to do?

Thanks to its exten­sive­ly trained neur­al net­work, DxO achieves a noise reduc­tion improve­ment of about 2-2.5 stops with Deep­PRIME and Deep­PRIME XD. This means that pho­tos shot at ISO 6400 processed in this way will have sim­i­lar lev­els of noise as unprocessed shots tak­en at ISO 1000-1600.

I already did an exten­sive com­par­i­son test of DxO DeepPRIME’s denois­ing with Lightroom’s built-in denois­ing some time ago. It can be found here on my web­site with many image exam­ples in my review of Pho­to­Lab 4. I men­tioned there that Deep­PRIME can even deliv­er a good 3 f-stops bet­ter result.

Accord­ing to DxO, Deep­PRIME XD has been trained with much more exten­sive data and is thus sup­posed to extract even more details (XD = eXtreme Detail). It does not replace the old­er algo­rithm, but is an addi­tion­al option that does not always deliv­er bet­ter results. See some exam­ples below for more information.

In my opin­ion, Deep­PRIME (XD) is cur­rent­ly the best image denois­ing tool avail­able, and in par­tic­u­lar, it’s orders of mag­ni­tude bet­ter than what I can achieve with the built-in algo­rithms in Pho­to­shop and Lightroom.

Deep­PRIME XD now rais­es the bar again.

PureRAW or PhotoLab 6 - which should I choose?

Pre­vi­ous­ly, I usu­al­ly avoid­ed using ISO val­ues above 3,200 in my dig­i­tal pho­tog­ra­phy, but now I also use the ISO range up to 12,800 with­out much hes­i­ta­tion if nec­es­sary. I am always amazed by the details that Deep­PRIME still gets out of the images.

I’ve been using DxO Pho­to­Lab reg­u­lar­ly since ver­sion 4, cur­rent­ly I’m using ver­sion 6, in par­tic­u­lar because of its Deep­PRIME XD enhance­ment. How­ev­er, I use it only for those noisy pic­tures that ben­e­fit from the inte­grat­ed Deep­PRIME algo­rithms. All fur­ther pro­cess­ing, orga­ni­za­tion, tag­ging and export­ing for print­ing or online pre­sen­ta­tion of my images is still done in Adobe Light­room Classic.

This also has his­tor­i­cal rea­sons for me. I have been a long-time user of Adobe Light­room since ver­sion 1.0 in 2007 and have edit­ed, orga­nized and also key­word­ed all my images in its inte­grat­ed data­base. Cur­rent­ly, that’s already over 200,000 shots. In addi­tion, Light­room has become very pow­er­ful over the years, it is also very per­for­mant and intu­itive to use.

In short, I am actu­al­ly 100% sat­is­fied with the pos­si­bil­i­ties of Light­room - only the inte­grat­ed algo­rithms for noise reduc­tion cur­rent­ly leave some­thing to be desired. There­fore, I bought Pho­to­Lab 4 in 2020 after an exten­sive test, despite the com­pa­ra­bly high price, only because of the inte­grat­ed Deep­PRIME process and since then I use it (cur­rent­ly in ver­sion 6) exclu­sive­ly via the inte­grat­ed Light­room plug-in. Unfor­tu­nate­ly, the stripped-down Pur­eRAW ver­sion was not yet avail­able at the beginning.

Pho­to­Lab 6 has become a very pow­er­ful tool for image edit­ing. I have had a look at the fea­tures for myself, and they leave lit­tle to be desired. Nev­er­the­less, because of my large stock of images orga­nized there, I still stick with Light­room Clas­sic for most of the image edit­ing steps and only use the Deep­PRIME (XD) plug-in.

Thus, for my pur­pos­es - and I think for the vast major­i­ty of peo­ple who are hap­pi­ly work­ing with Adobe Light­room - the new Pur­eRAW 3 would now be per­fect­ly sufficient.

Installation

There is actu­al­ly not much to say about the instal­la­tion. After down­load­ing the set­up file from the DxO serv­er, it starts and installs the stand-alone Pur­eRAW 3 pro­gram (which I won’t dis­cuss fur­ther below) and the plug-in for Adobe Light­room, which is the sub­ject of this article.

The first time you launch Light­room Clas­sic after installing Pur­eRAW 3, you will be noti­fied that a new plug-in is available.

If you take a clos­er look in Light­room Classic’s Add-on Mod­ule Man­ag­er, there are actu­al­ly two plug-ins installed:

The first pass­es a file select­ed in Light­room into DxO Pur­eRAW 3. The sec­ond then merges the file edit­ed in Pur­eRAW back into Lightroom.

By the way, you have to have some patience for this. The re-import does not take place direct­ly after edit­ing in Pur­eRAW - it hap­pens a bit lat­er. I there­fore ini­tial­ly thought that this was­n’t work­ing and there­fore import­ed the DxO files myself via a syn­chro­niza­tion of the direc­to­ry in Light­room Clas­sic. This then led to an error mes­sage after the sub­se­quent auto­mat­ic start of the DxO import process. So: you should have some patience there.

My workflow

I edit my pic­tures as I have already described here and here for years in Light­room Clas­sic in sev­er­al steps.

After a shoot, I first briefly review all the images in the library mod­ule and delete any obvi­ous­ly unus­able images (blurred, gross­ly under­ex­posed, out of focus, etc.).

Then I usu­al­ly go through them in chrono­log­i­cal order in a sec­ond pass in the Devel­op mod­ule. There­by I make first short edit­ing steps (crop­ping, rough expo­sure cor­rec­tions, white balance).

If there are sev­er­al images in a series, I then syn­chro­nize the pro­cess­ing to all images in a series. Dur­ing this first pro­cess­ing I mark the images. Images that I want to keep and process fur­ther get a mark­er (key ‘P’ for ‘pick’). Images that I am sure I do not want to edit, are marked with the ‘X’ key for sub­se­quent dele­tion, the rest remains unmarked.

In the third step, I only look at the marked images in more detail by select­ing them. This usu­al­ly leaves me with only about 15-30% of the orig­i­nal images. For these, a more detailed pro­cess­ing with all options of the Light­room devel­op­ment mod­ule fol­lows. Images that I like par­tic­u­lar­ly well are now rat­ed by me with a star (key ‘1’) at first.

And just now, in my work­flow, DxO comes into play.

DxO DeepPRIME integration

If I now notice that a par­tic­u­lar image still has a lot of noise after pro­cess­ing, it is now hand­ed over to the DxO plug-in for fur­ther pro­cess­ing with Deep­PRIME. The trans­fer is done some­what unin­tu­itive­ly via the Plug-in Extras menu item in the file menu:

After start­ing Pur­eRAW 3, which takes a moment, the first thing that can be done is to select the rec­og­nized cam­era and optics mod­ules. In my exam­ple it’s my EOS R5 with the EF 16-35mm f/4L IS USM:

If you don’t want to do any opti­cal cor­rec­tions in Pur­eRAW, you can sim­ply omit these mod­ules with “None of above”. After­wards the options win­dow will appear:

For all my RAW pro­cess­ing, I exclu­sive­ly choose Deep­PRIME or Deep­PRIME XD as denois­ing method.

Regard­ing the choice of opti­cal cor­rec­tions, every­one has to decide for him­self if he wants to han­dle this by Pur­eRAW or lat­er by Light­room. In the exam­ple, I just use Pur­eRAW for every­thing except the lens dis­tor­tion cor­rec­tion, which I don’t always want to use. I leave the lens sharp­ness cor­rec­tion at the pre­set val­ue ‘Stan­dard’.

Output formats

Since I still want to edit the images in Light­room, I only choose DNG as out­put for­mat. Since this is a lin­ear DNG for­mat, you have to accept that the result­ing file will be a good 3 times as large as the orig­i­nal RAW file from the camera.

This is because the lin­ear DNG for­mat con­tains the cal­cu­lat­ed red, green and blue col­or val­ues for each image pix­el (i.e. three val­ues), while the camera’s orig­i­nal RAW for­mat stores only one col­or val­ue cor­re­spond­ing to the Bay­er col­or fil­ter in front of the pix­el in ques­tion (i.e. red or green or blue).

The default des­ti­na­tion is a sub­fold­er named ‘DxO’ in the direc­to­ry of the file to be processed. How­ev­er, as an addi­tion­al option, I would like to be able to write the DNG file with the suf­fix ‘DxO’ to the same direc­to­ry, sim­i­lar to Pho­to­Lab. Alter­na­tive­ly, you can also select any oth­er fold­er here.

If you now scroll down in the options win­dow, you can choose whether the edit­ed file should be renamed. There­fore you can add a pre­fix or suf­fix to the orig­i­nal file name. The suf­fix ‘RAW pro­cess­ing method’ is the default and in my opin­ion a good choice.

Final­ly, you can spec­i­fy where you want to export the edit­ed file. For my work­flow, the export to Adobe Light­room Clas­sic is already pre­set. Alter­na­tive­ly, you can trans­fer the processed file to Adobe Light­room or any oth­er soft­ware of your choice.

After select­ing the options, the actu­al pro­cess­ing can now be start­ed. Depend­ing on the hard­ware installed in your com­put­er, more or less patience is required.

The graph­ics card installed in the com­put­er is in par­tic­u­lar time-crit­i­cal. On my lap­top with an nVidia RTX 3080, pro­cess­ing a 45 megapix­el file from the Canon EOS R5 takes 15-20 sec­onds. On old­er hard­ware, how­ev­er, this can take sev­er­al minutes.

After pro­cess­ing, DxO Pur­eRAW 3 clos­es auto­mat­i­cal­ly and Light­room Clas­sic returns to the fore­ground. How­ev­er, the re-import of the processed image still takes a while; in my expe­ri­ence, after about 30-60 sec­onds, it is import­ed into a new­ly cre­at­ed col­lec­tion in the ‘DxO Pur­eRAW 3’ fold­er. This has as its name the date and time of the processing.

Results

So far - so good. We have now suc­cess­ful­ly used Pur­eRAW 3. How does it improve on the noise reduc­tion in Adobe Lightroom?

A lot. Here is an example:

We recent­ly vis­it­ed the famous Fushi­mi Inari-Taisha Shrine in Kyō­to on a dark and rainy day in Japan. This world famous shrine con­sists of thou­sands of orange-red torii stand­ing direct­ly behind each other.

With­out a tri­pod and with an f/13 f-stop nec­es­sary because of the required depth of field, I had to take the pho­to at ISO 12800 despite a rel­a­tive­ly long expo­sure time of 1/25 second.

On the left, you can see the image processed with Light­room, and on the right, the image denoised with DxO Pur­eRAW 3. Admit­ted­ly, the dif­fer­ence is not very notice­able in the down­sized image. But in the 400% mag­ni­fi­ca­tion you can see what Deep­PRIME XD can get out of the noisy original:

I still think the result is very impressive.

DeepPRIME vs DeepPRIME XD

New com­pared to ver­sion 2, Pur­eRAW 3 now offers the new Deep­PRIME XD in addi­tion to the well-known Deep­PRIME process, which is sup­posed to get even more details out of the orig­i­nals. DxO adver­tis­es the XD ver­sion not as a replace­ment, but as a addi­tion to the already very good Deep­PRIME process. This is not with­out reason.

On the one hand, the com­pu­ta­tion­al effort of image pro­cess­ing has increased even fur­ther due to the even more com­plex neur­al net­work in Deep­PRIME. Both meth­ods make inten­sive use of the capa­bil­i­ties of mod­ern graph­ics cards. With old­er, less pow­er­ful graph­ics cards, the time required for Deep­PRIME XD to process a high-res­o­lu­tion RAW file can be in the range of min­utes. But even on more pow­er­ful mod­ern com­put­ers Deep­PRIME XD needs sev­er­al sec­onds per image. In my own test, the new­er Deep­PRIME XD method some­times need­ed 6 times as much com­put­ing time as the orig­i­nal Deep­PRIME. With cur­rent pow­er­full graph­ics cards, how­ev­er, the time dif­fer­ence is insignificant.

On the oth­er hand, some­times you get the feel­ing with cer­tain RAW-files that Deep­PRIME XD tries a bit too much and adds details that are not there.

Accord­ing to my reviews so far, Deep­PRIME XD has par­tic­u­lar advan­tages in bring­ing out fine reg­u­lar struc­tures, such as the hairs in fur. Here is an exam­ple from my review of DxO Pho­to­Lab 6:

The image on the right, devel­oped with Deep­PRIME XD, reveals much more and more nat­ur­al look­ing details in the fur of the ser­val, espe­cial­ly around the nose.

Also, com­par­ing my ISO 12,800 test shot of a stuffed ani­mal from my review of Deep­PRIME in Pho­to­Lab 4 shows slight­ly bet­ter res­o­lu­tion when processed with Deep­PRIME XD. Here you can see the scaled down image first:

Admit­ted­ly, there are hard­ly any dif­fer­ences in the scaled down image. They only become sub­tly vis­i­ble in the 400% crop:

The dif­fer­ences are admit­ted­ly small. Nev­er­the­less, the pro­cess­ing with Deep­PRIME XD actu­al­ly reveals more details and less noise. What one prefers in each case, how­ev­er, is admit­ted­ly a mat­ter of taste.

Disadvantages?

But the pro­cess­ing with the new XD method is not always advan­ta­geous. Here is an exam­ple where I per­son­al­ly like the ear­li­er process a bit bet­ter. It is again a recent shot with my Canon EOS R5 of the famous Fushi­mi Inari-Taisha shrine in Kyōto.

With­out a tri­pod and with the nec­es­sary stoped-down aper­ture (f/13) because of the required depth of field, I again had to take the pic­ture with ISO 12,800 despite a rel­a­tive­ly long expo­sure time of 1/25 second.

Here again, the image tak­en with DxO Deep­PRIME on the left and DxO Deep­PRIME XD on the right are com­pared. First, the com­plete image, which again does not reveal any sig­nif­i­cant dif­fer­ences due to its reduc­tion in size:

Only the 400% crop blow-up reveals the dif­fer­ences here:

In this exam­ple, I think Deep­PRIME XD did too much and “added” details that are not there, both in the lantern and at the bot­tom of the torii columns. Here I pre­fer the result of the old­er Deep­PRIME process.

By the way: 

if you have any doubts about the per­for­mance of both meth­ods, here is an exam­ple of the two crops above with the denois­ing as I man­age it with Light­room alone:

There are worlds between both processings!

Comparison with Topaz DeNoise AI

Almost two years ago, I com­pared the two main com­peti­tors in denois­ing high-ISO images: DxO Deep­PRIME vs. Topaz DeNoise AI. Both are based on AI algo­rithms trained with large amounts of data.

In my pre­vi­ous test, I found that DxO Deep­PRIME per­formed much bet­ter than Topaz DeNoise AI. As some time has passed in the mean­time and Topaz has also released new­er ver­sions of DeNoise AI, I had my above exam­ple processed with the cur­rent ver­sion 3.7.2 of Topaz AI Topaz AI once as well.

Regard­ing per­for­mance: On my com­put­er (lap­top with i9-11980HK and RTX 3080), Topaz AI takes much longer to process the RAW file of my Canon EOS R5 than Deep­Prime. It took 80 sec­onds for the image to get processed. Here is the result in com­par­i­son to DeepPrime:

Over­all, Topaz­De­Noise AI now process­es RAW files much bet­ter than in my pre­vi­ous test. The results are quite good, espe­cial­ly when com­pared to the above result from Light­room alone. Still, I see some arti­facts in the lamp (dou­ble con­tours in the side­bar). The sur­faces also look much more jit­tery. In direct com­par­i­son, I still pre­fer the result from DeepPRIME.

Résumé

Pur­eRAW 3 is a wel­come enhance­ment. It fits seam­less­ly into my work­flow with my usu­al work­flow of edit­ing with Adobe Light­room Clas­sic. That is, it would if I did­n’t already own Pho­to­Lab 6 and were already using the plug-in that also comes with it there.

Nev­er­the­less, Pur­eRAW 3 would cer­tain­ly suf­fice for my needs at the moment. I don’t use the addi­tion­al exten­sive capa­bil­i­ties of the larg­er Pho­to­Lab 6 in my work­flow, so I could have saved some mon­ey by using DxO Pur­eRaw 3.

How­ev­er, I would like Pur­eRAW 3 to add the abil­i­ty to save the edit­ed images to the same fold­er as the orig­i­nals, as this has been my usu­al way for years.

Both DxO pro­grams con­tain what I con­sid­er to be the best tech­nol­o­gy cur­rent­ly avail­able for pro­cess­ing noisy images. The new­ly added Deep­PRIME XD in Pur­eRAW 3 and Pho­to­Lab 6 can extract even more fine details from suit­able images. From my gut feel­ing, I would esti­mate the gain over Deep­PRIME then to be about 1/2 to 1 f-stop. But some­times Deep­PRIME XD is too much, so I’m grate­ful that DxO con­tin­ues to offer the old­er DeepPRIME.

If you haven’t had any expe­ri­ence with Deep­PRIME yet, I high­ly rec­om­mend down­load­ing the free tri­al ver­sion of Pur­eRAW 3 (direct­ly here at DxO*) and giv­ing it a try. DxO is extra­or­di­nar­i­ly gen­er­ous and allows you to test its pro­grams for 30 days with­out any restrictions.

Those who, like me, have been used to using Light­room Clas­sic or anoth­er RAW devel­op­ment pro­gram for many years can enhance it effec­tive­ly with Pur­eRAW 3.

How­ev­er, if you haven’t yet built up a large image data­base and are still com­plete­ly open in this regard, I rec­om­mend tak­ing a clos­er look at DxO Pho­to­Lab 6*. Per­haps this solu­tion offers every­thing you need in one sin­gle program.

Those who already use Pur­eRAW 2, on the oth­er hand, will have to con­sid­er whether Deep­PRIME XD’s slight improve­ments jus­ti­fy an upgrade. Here I rec­om­mend sim­ply check­ing it out for your­self with the free tri­al version.

How­ev­er, the improve­ments in Deep­PRIME XD alone moti­vat­ed me to upgrade from Pho­to­Lab 5 to ver­sion 6, which was even more expensive.

*= Affil­i­ate Link