Speed Up Exports that Use Prime Noise Reduction?


I use DxO PhotoLab and wish it was faster both editing (e.g. entering Local Adjustments) and exporting with Prime NR. I typically process raw images from a Canon 5D3 which average around 36 MB. PhotoLab is configured to enable OpenCL and process 2 images at once. I’m running Windows 10 64 bit.

My PC has an Intel i7-4770 processor, 300W PSU, 12 GB DDR3-1600 memory, 3 TB SATA HDD, and an Nvidia 2 GB GeForce GT720 display card. With that configuration I can process raw files at max of around 28 sec. per image. When testing export I see around 3 GB memory usage, 99% CPU usage, and very little disk I/O.

I’ve spent some time poking around various forums but haven’t seen anything that directly responds to these questions. From what I read memory isn’t an issue and an SSD wouldn’t help, but a faster CPU or display card might be helpful.

Can anyone tell me how this performance compares to that of more powerful and expensive configurations? If I’m already close to maximum performance then I won’t spend time and effort if I’ll only get minimal improvement.

If I do try to improve processing speed would a faster graphics card be a good option? My thought is that trying a faster card, probably around the most powerful that would run with the 300W PSU, would be a reasonable option to try. Any idea how much my processing time per image would be reduced if I tried that? If not should I try something else? I’d be willing to spend some money to get some improvement but I’m not willing to dump a lot of money to get a gaming-class PC.


Welcome Mike. I’m the resident advocate for faster performance, albeit on Mac, as a top priority for the DxO development team. Be happy you are using PhotoLab for Windows. Recent versions have been much faster on Windows than Mac, OpenCL optimisation seems to work on Windows and doesn’t on Mac. I’m less worried about export times (with Prime NF on, about 2 minute per image for my 5DS R images, about 40 seconds per image for my A7 III images) than about real time sliders for fluid artistic work.

Waiting 5 to 12 seconds on a slider kills any creativity. The way to avoid really slow sliders is to avoid turning on either Lens Sharpness or Noise Reduction until right before export.

Based on your configuration, more CPU cores should help, particularly when processing two images at a time. My 12 core Mac manages to use about eight of the cores when exporting just single images. More memory would probably help when processing or multi-tasking but probably would not directly help export.

So I’d suggest upgrading to an 8 processor machines, either single CPU unit or dual CPU. I’d be very curious to see benchmarks with various graphic cards. On my Mac it wouldn’t make much difference, as I already have a Radeon RX580 (close to top of the line). Radeon cards seem faster than Nvidia cards but I don’t have empirical data as one machine is 12 processor and the other is 6 processor. If you could get ahold of a better Radeon card to benchmark in your existing system for both export times and slider fluidity that would be very, very useful to the Windows PhotoLab community.

1 Like

Hey Guys,

Yeah, exporting with PRIME is painful for me on my iMac…

So is there a plan for DxO to work on taking advantage of Mac based GPUs? Would be good to know and hope for…

  • Thanx!
  • Jon

Your machine is a good configuration
But you neglected the SSD. Its a good way to improve PhotoLab.
Your processor is on the top and there is no specific GC for photos
But a good 4k screen is recommended.


4K screen will slow down PhotoLab yet more, at least on Mac (not the original poster’s situation). I don’t know if 4K screen slows down the sliders on Windows.

Why ?

As stated, an SSD or m.2 in your case would yield a noticeable improvement.

I’m starting to gather components for my next system. Going with aZ390 chipset and i9, 2070 or 2080 graphics, m.2.

My current PL system below is pretty fast, even though its several years old. I think I avg about 12 sec. Maybe even a little faster if I recall. My RAID is what makes this machine “work”. Processor is my bottleneck. I’m 6D2, avg 35 MB.

Z97X-UD5H (F8) \RM850w, 4790K, 16GB Vengeance, GTX970 FTW SC, 850 Pro’s RAID 0, 1TB WD, W10 1809

1 Like

Well, 4K main screen certainly slows down responsiveness PhotoLab 2 on a Mac Pro. Sometimes the program is more responsive on my MBP. I have to be careful about absolutism though as I process images from three different cameras regularly in PhotoLab: 5DSR, 5DIII, A7III. It may be that on the MBP I’m working more often with A7III 24MB images so it seems more responsive.

Quantifying responsiveness in an interface is difficult. I can promise you one thing: waiting 8 to 15 seconds on “Correction Preview” for every change is not responsiveness. That’s what PhotoLab 2, a 12 core Mac Pro with Radeon RX580 and very fast SSD will get you with Lens Correction and Noise Reduction palettes enabled.

Am I losing patience for this poor performance? Yes, I am. Workaround as I’ve said: no Lens Correction or Noise Reduction until export. Convenient, no. Even then the “Correction Preview” wait is usually three to five seconds.

And no, I have no performance issues with any other applications on two different Mac Pro (the other with 6 core and Nvidia GTX 980). I’m dismayed by the blame the messenger crowd here who consistently try to suggest that I have underpowered or poorly configured hardware.

No, PhotoLab 2 is horribly slow with 4K monitor setup (second monitor too but it’s not 4K) and large files like the 5DS R files. I don’t mind the two minute export but I’m really frustrated by the non-responsive sliders.

Yes Alec. This is a known issue and, at this moment, DxO develop a new display engine.
But I don’t see any effect of a 4K screen but the raw image size of course yes.


Pascal, that’s good news that a new display engine is on its way. It will help all of us who regularly develop moderate to large numbers of photos in DxO PhotoLab. Very glad to hear it. Any idea on when the new display engine will be released or put into beta?

This information is public. This new engine is used in the full screen and Local adjustments modes.

I don’t have 4K screens to test with (Windows). At 2K slider processing (preview) changes are pretty much instantaneous. (real time). De-Noise is enable 100% of the time, Lens profiles too. Smart Lighting as well. My only lag is batch export. Just a matter of me building a new machine if I stay at 2K.

You are shooting the Canon 6D Mark II? For the record, that’s a 26 MP camera with 6240 × 4160 pixels, in file size about equivalent to the A7 III on which I have much lower lag than on the 5DS R. Could you test with some Canon 5DS R files?

I’ve uploaded a few here. 5DS R files are too big for the direct upload to forum.dxo.com – it looks like DxO really don’t like files over 50 MB, not in PhotoLab not on the forum. These files are ISO 6400 so they should give PhotoLab a good workout. You can download all three at once by clicking Télécharger le dossier in the upper right hand corner.

@mwsilvers I believe you had asked about some 5DS R files? There they are.

1 Like

I use a 5DS and yes PL struggles (Windows version). Using prime, local adjustments and most changes are slow. The others I use are Sony a600 and Canon 7D2 both are 1/2 the file size I know but changes are very much faster and exports are on a different level. 5DS corrections even in windows are sluggish and if I have a adjustment I am copying over 10-15 images solitaire comes in handy for time filling as it does for exporting! If you delete 5DS you have to allow a full time for a load before deleting or all you get us “unknown error” have have to repeat it. I find you just have to expect to take a long time to deal with them which I can see some one with lots of images might not what to have to allow for. I expect it stems from PL being developed before such large files became so much more widely used.

1 Like

Thanks John for the field report. It’s both a relief and a worry to know that 5DS/5DSR (and probably D850, A7Rx files too) are very slow on the current Windows engine. It behooves DxO to improve the processing engine (probably mainly by adding a proxy front end version for adjustments along with GPU acceleration, exports will continue to be slow, it’s a lot of data to move. Adobe found GPU acceleration should not be used for pixel perfect final exports) before adding more modules like DAM solution.

If PhotoLab is cripplingly slow with the current cameras (64 to 100 MB are on their way apparently, not that I’m lining up for it), how do DxO expect professional photographers to even consider PhotoLab? Well apart from rescue software for very high ISO images. Most pros avoid those kind of images in any case. My first question to DxO management would be: Is PhotoLab software for amateur users with low to medium resolution cameras only?

Export is less an issue Jon, I think, than fluidity of interface when editing. If there’s a big rush job, HQ Fast noise reduction is more than adequate: my export times drop from close to two minutes per file to twenty to thirty seconds. I sometimes prefer HQ Fast in fact, as it looks more like film grain, whereas Prime can create this sort of artificially clean look, particularly in large doses. I usually set Prime at about 12 which strikes a balance between reduced noise and a natural appearance.

Keep in mind that for export, DxO won’t be able to use GPU acceleration as there are fine errors in colour and detail which come up. Not an issue for preview, but not what you want for final output. These errors are why Adobe has problems with GPU acceleration for final output in Premiere.

In short, I’m not worried about the long export times but I’m really worried about how long it takes to go through a session with larger files due to the delay on the sliders. Delays during editing discourage experimentation and fine tuning, making PhotoLab less attractive to work with.

1 Like

Yeah, I hear you and agree that fluidity of the interface is a BIGGER issue, but I’d still love to see some speed improvements to the exporting with PRIME.

  • Jon

Hi Alec!

Based on the images You provided I believe it is more likely the 4K screen res (readout) that is causing the problems… using one of the images You provided “8M8A3121-C1.CR2” (78.3 MB) as the basis for my supposition.

I am using a fully loaded mid-2011 iMac (High Sierra) 27" 2K monitor; PhotoLab (1.2.2); Nikon D70 (6 Mp); D300 (12 Mp); Sony DX100 series (20 Mp) as touchstones in the following comparisons.

My hardware is definitely not state-of-the-art which I believe lends more credence to my initial supposition.

There is no significant difference between the on-screen updates of the D70; D300; RX100 images or your image on my system. They occur for the most part near instantaneously - even when using “Lens Sharpness” or “Prime Noise Reduction”. “Local adjustments” ditto.

The “loupe” image for “Prime Nose Reduction” has exactly the same pixel dimensions for any of the different camera resolutions mentioned above. So the loupe updating should not be a factor vis-a-vis image resolution. The same amount of pixels being processed.

The 100% screen proxy updates (accurately) at the same time as the loupe what ever the image resolution.

Below is a “screen recording” example of PL’s “loupe” from your 78.3 MB image - as I move from selected area to selected area (which takes a couple of seconds when I move the mouse and click a new selection area). Note the only time the “circular arrow” update icon shows up is on one of the noisier samples (last one - “White Shorts”) - not even 2 seconds. Otherwise updates are nearly instantaneous.

Just below this video is a screen capture of the original “White Shorts” image (with noise).

“White Shorts” screen capture (w/noise)


Thanks to everyone for taking the time to respond.

First I feel really lucky that I’m on a PC instead of a Mac. My 28 seconds isn’t bad considering what you’re all seeing. I have a 4K monitor and I haven’t noticed significant problems with the sliders even though I turn on Prime early in my workflow and I never turn off Lens Sharpness. I notice a minor degradation if I’m editing and exporting at the same time but not enough to stop doing it. The sliders aren’t as smooth as I’d like but it’s not a problem.

Doubling my export throughput with more processing cores would be great. I’d love to do it but I’m just not ready for that cash outlay. The only thing I can consider now are cheaper upgrades, probably a more powerful display card and/or SSD.

My next step is to see if I can borrow a more powerful display card that will work with my 300W PSU and see what happens. If that helps then I’ll upgrade to a better card, maybe a GTX 1050 Ti. Re the SSD I’m not sure what to think. When I’m exporting or editing I see next to no drive activity, either watching the light or the MS Task Manager, so it seems unintuitive that an SSD would speed up PhotoLab. But even if an SSD didn’t help PhotoLab that much it would still make the machine much more usable because it speeds up so many other things.

If I can install a borrowed or bought display card or SSD I’ll report back on my results.


1 Like

I have better performance on Mac with Radeon cards (even an old 6750 in my 2011 MBP 17" i7) than with Nvidia. PhotoLab is apparently running with OpenCL which sometimes performs better on Radeon cards. Even an nVidia GTX 980 doesn’t seem very spritely on my six core Mac Pro. This may be platform specific – it would be great if DxO offered some more detailed information about which cards run well and which ones less well. This is all they tell us:

Windows: OpenCl 1.2-capable graphic card with 1GB of video memory to handle OpenCL acceleration
Mac: Graphics card with 512 MB of video memory to handle GPU acceleration

I’m disappointed to see the latest versions require at least 10.12 on Mac. My main working environment is OS X 10.11 and I don’t plan to change that as 10.11 is very stable and headache free. I do keep one computer (my main video and photo computer) with 10.14 for video application (FCPX specifically). Not supporting older versions of OS X will alienate many photographers who would prefer to work on their pictures than spend timing fighting their OS.

There’s no new technology in PhotoLab which requires the latest OS. Apple does make it hard for developers to support older OS by deliberately making them the latest xCode unable to build for older OS X. The workaround is either to use an older xCode for the main build (older versions will run on newer OS of course) or to do two builds. FastRawViewer manages to do this.