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Mod­ern cam­era sen­sors are becom­ing more and more light-sen­si­tive and pro­duce con­tin­u­ous­ly less noise. Image pro­cess­ing soft­ware is also evolv­ing. Par­tic­u­lar­ly since the appear­ance of AI (arti­fi­cial intel­li­gence) algo­rithms, there are con­tin­u­ous­ly improv­ing pos­si­bil­i­ties for noise reduc­tion with high-ISO images. Nowa­days, use­ful results can even be achieved with images tak­en at ISO 12,800, some­thing that was mere­ly incred­i­ble just a few years ago.

I’ve recent­ly start­ed using the Deep­PRIME algo­rithm devel­oped by DxO, which is includ­ed in DxO Pho­to­Lab 4 Elite and, more recent­ly, in DxO Pur­eRAW. I use both pro­grams exclu­sive­ly for noise reduc­tion; all fur­ther pro­cess­ing is done in Adobe Light­room Clas­sic, as I have been accus­tomed to for years.

More infor­ma­tion about the DxO pro­grams can be found here on my web­site, where I have already test­ed both:

DxO Pho­to­Lab 4 Elite
DxO Pur­eRAW

Since I was told by sev­er­al peo­ple that excel­lent noise reduc­tion is also achiev­able with Topaz Denoise AI, I want­ed to test Topaz Denoise AI myself and com­pare the results with those of the Deep­PRIME algorithm.

Spoil­er: unlike DxO Pho­to­Lab 4, I won’t buy the full ver­sion of Topaz Denoise AI - the rea­son follows…

To com­pare, I down­loaded the tri­al ver­sion of Topaz Denoise AI from the link above and used it with an ISO 12,800 image from my pho­to library to eval­u­ate its results against those of DxO Pho­to­Lab 4 and DxO PureRAW.

I tried to final­ly edit all images in Light­room Clas­sic so that col­ors, con­trast and bright­ness are as sim­i­lar as pos­si­ble. Here, first of all, you can see the orig­i­nal ver­sion of the image, inten­sive­ly processed in Light­room to my taste (Expo­sure -0.66, Con­trast +58, High­lights -100, Depths +100, Clar­i­ty +28, Dynam­ics +21, Denois­ing and Sharp­en­ing to Stan­dard), down­sized to 1600px long edge. The result is still clear­ly noisy even in the reduced version:

Here are two more crops in 100% scale:

I then passed the image as a CR3 file from Light­room Clas­sic to DxO PhotoLab4, where it was denoised using the Deep­PRIME algo­rithm (Lumi­nance set­ting 100). this is in accor­dance with my usu­al work­flow. After­wards, it was con­vert­ed again with the option

„Export as DNG (Noise reduc­tion & opti­cal cor­rec­tions only)“

as a DNG file back to Light­room and post-processed so that bright­ness, col­or sat­u­ra­tion and con­trast were com­pa­ra­ble. The fol­low­ing crops show the result of this treat­ment in 100% view again - it looks very much bet­ter now:

And now the same with DxO Pur­eRAW with default set­tings (you even can­not adjust any­thing there 😉 ). Although Pur­eRAW also uses the Deep­PRIME algo­rithm, the result is dif­fer­ent. There is a slight amount of remain­ing noise in the back­ground, and the plumage is already mar­gin­al­ly over-sharpened:

All in all, while Pur­eRAW is still very usable, I real­ly pre­fer the results with the Deep­PRIME options in DxO Pho­to­Lab 4.

And what about Topaz Denoise AI?

Now fol­lows the inter­est­ing com­par­i­son with Topaz Denoise AI: In ver­sion 3.0.3, Topaz Denoise AI can direct­ly edit the CR3 RAW files from my EOS 5R. I there­fore start­ed by load­ing the orig­i­nal CR3 file of my Canon EOS R5 into Topaz Denoise AI. Then I used the auto­mat­ic set­ting to remove the noise and saved the result as a DNG file. I then re-import­ed this into Light­room. Basi­cal­ly, this is the same approach that I took above with DxO Pho­to­Lab 4 and DeepPRIME.

How­ev­er, the result­ing image looks very dull and dark at first, so that I had to make exten­sive cor­rec­tions to achieve a com­pa­ra­ble result to the one I had pre­vi­ous­ly got in Light­room. Here is my result in a scaled-down full image to demon­strate, that the result is some­what com­pa­ra­ble in terms of bright­ness and color.

The image con­tains a water­mark because I used the test ver­sion of Topaz for the review. This is anoth­er plus for the DxO soft­ware: it can be used with­out restric­tion and put through its paces, at least for a gen­er­ous test peri­od of 31 days.

Even the scaled-down ver­sion is not very impres­sive, which is unfor­tu­nate­ly con­firmed in the 100% crops. The result is even sig­nif­i­cant­ly worse than what I achieved with Light­room Clas­sic alone:

Thus, in my opin­ion, direct pro­cess­ing of CR3 raw files with Topaz Denoise AI is cur­rent­ly not of any use.

I have there­fore used Topaz Denoise AI direct­ly with Light­room. From there, the image can be trans­ferred to Topaz Denoise AI as a 16bit TIFF file using the menu item “Edit in…”. At first, I used the auto­mat­ic set­tings in Topaz Denoise AI (Noise 40 Sharp­en­ing 28, Rest 0):

This is already bet­ter, but still does­n’t come close to the DxO Deep­PRIME results. The image also seems over-sharp­ened to me and there is still clear­ly vis­i­ble resid­ual noise. Note in par­tic­u­lar the arti­facts at the back of the head and the noise between the legs. I there­fore tried to improve the result man­u­al­ly (set­ting Noise 60, Sharp­en­ing 18):

I like this ver­sion bet­ter, but it still con­tains arti­facts between the legs and at the back of the head.

I then denoised the image once more with Topaz Denoise AI using the “AI Clear” set­ting, which is sup­posed to gain bet­ter results with high-ISO shots, and left the rest of the pro­cess­ing as before.

First the auto­mat­ic set­ting, here Topaz Denoise AI Clear sets the denois­ing lev­el to Medium:

Since that was still very noisy, I changed the denois­ing set­ting to High, then it looks like this:

Well, the arti­facts are par­tial­ly gone, but I’m still not real­ly thrilled with the result with the AI Clear setting.

All in all, Topaz Denoise AI is already very good, at least bet­ter than what I can man­age in Light­room alone. How­ev­er, the DxO Deep­PRIME algo­rithm seems much bet­ter to me. In addi­tion, Topaz Denoise AI is, in my opin­ion, cur­rent­ly not rea­son­ably usable with RAW files (at least with those of my Canon EOS R5).

DxO Deep­PRIME, on the oth­er hand, clear­ly ben­e­fits from pro­cess­ing the RAW files, which is not sur­pris­ing since DxO can per­form noise reduc­tion even before demo­saic­ing the Bay­er matrix and can there­fore use much more image information.

Maybe Topaz Denoise AI or oth­er pro­grams can achieve even bet­ter results, I am very curi­ous. How­ev­er, for now, I will con­tin­ue to use DxO Deep­PRIME to process my noisy high-ISO images.

But if you want, you can use the soft­ware of your choice to work on the RAW file I used here. You can find and down­load it here.

I look for­ward to your com­ments and edits.