Two essential differences between ON1 Photo RAW and DxO Photolab 4

ON1 Photo RAW reads PEF files from all Pentax DSLRs and not only a selected few.

And, unlike DxO, they’ll give you a refund if you’re unhappy with your purchase, even after registering the product. And no, they also have a fully functional demo version.

So, thanks to DxO for a lesson in careful spending.

Not that I’m a fan of DxO’s refund or licensing policies, but there is a list of supported cameras here, and the few (4 of 25) is those that don’t have PEF supported. Maybe there are some cameras missing, but everything at least somewhat recent seems to be covered. (K-5 through K-1 in my case.)


Maybe it’s because the refund has often been necessary with ON1 products :grin: ? I’m not a DxO evangelist but I have been using DOP/DPL since the very beginning and I never had with DxO the really bad experiences that I had with ON1. I have learned that there are engineers behind these products, not marketers having a smart mouth. Unlike ON1, they never promised more than they could actually offer (with the single exception, a few years ago, of a really badly formulated marketing campaign about the Nik Collection). One “essential difference” between DxO and ON1 (and Adobe, by the way), is the customer support dpt. responsiveness. Not perfect but at the top of the list, IMHO.

NB : Everyone here knows that I’m not especially forgiving when reporting problems or design mistakes (understatement). But at least, I have someone knowledgeable to talk to. This doesn’t happen very often nowadays.


The OP joined a day ago and has posted just once with the clear intent of bashing DXO. it seemed to me to be very troll like behavior. I own ON1 and stopped using it because PhotoLab is a superior product regardless of ON1’s larger feature set.

Further, DXO provides a 30 day unrestricted free trial of Photolab. If someone purchases Photolab after testing it for 30 days, why would they want a refund. Unfortunately, a number of people buy before trying and realize that their hardware, operating system, or camera is not supported, or they realize that certain features important to them are not available. That is why the 30 day free trial is so important.



No, mwsilvers, I am not a troll. But I’ve had my share of experiences with forums and their population of fanboys (or girls) over the years, so I tend to avoid them or only join them as a last resort.

I have spent about two weeks with the demo version, albeit with a limited selection of RAW files on a separate drive in order not to mess up my ‘normal’ files. Eventually, I was tempted into buying PL4 by the Black Friday promotion.

After buying and registering the software, I switched over to my regular photo directories - which are admittedly rather big - to find that PL4 came to a screeching halt opening them. And no, before anyone suggests otherwise, my computer is a 2 month old Mac with a 6-core i7 processor and 32 GB of RAM.

I have to admit I was shocked about the speed. Worse still than ON1 2021 which by itself is quite bad enough. Yet, my old Lightroom 6 - in spite of its age and various deficiencies - still runs circles around both on the same machine. Might have to do with the fact that LR6 creates catalogs with thumbnails and the two others don’t.

When I tried to use the indexing function to speed things up, PL4 gobbled up practically all my RAM and then apparently resorted to swapping data to and from the hard drive until the total memory usage indicated by my activity monitor reached several hundred GB and the whole system became totally sluggish.

Now, if this is the work of engineers, as Pat91 suggested, then that reminds me of the old joke about the three ways of ruining a company: gambling (fastest), women (most fun) and engineers (safest).

The problem with several thousand PEF files from my older Pentax cameras not being recognised was only the last straw.

With regard to your regular folders how big is big? How many files are we talking about on average in one of these folders? How big are your raw files?

While my folders may not be as big as yours, and I’m running on Windows 10, Photolab runs rings around ON1 which is massively sluggish on my machine.

Of course the far better performance I’m seeing with Photolab is less important than the significantly superior results I get with it.



Hello Ralf,
something must be wrong. I am on a imac 2012, Mojave and it runs fine with DPL. I have folders with up to 5000 raw files in each of them.

  • Indexing can be demanding. My folder structure is Pictures>Originals>Year. Selecting “Originals” might bring the computer to a halt. In my case I would select “Year”. This might help. Remember once it is indexed there is no need to repeat that again.


That’s about my directory sizes as well. I’m still wondering about the indexing. It takes ages, slows everything down to almost a standstill and on the next day things are just as sluggish as before. Indexing doesn’t seem to speed things up here.

My directories (per years) vary between a few hundred and around 13,000 files with single files evolving from 10 megs with the older cameras to around 35 now.

Opening a directory takes up to 30 minutes which makes the output quality a rather moot point.

Indexing will speed up your searches - in case you do that within DPL. Contrast etc… will not become faster because of indexing. In my case I do the searches within my DAM so indexing is not so important for me.

Have you tried indexing one specific folder (no subfolders in it) only? Whats happening then.
I do not even want to mention a restart of the computer:)

Tried it all, exited and re-launched DPL (that at least frees up all the RAM), had the computer have a good night’s rest… all to no avail. Next time I open a directory, it again takes ages just to show the thumbnails.

Worse still, leaving and re-launching the software seems to get rid of all progress made and everything starts all over again.

How long are you leaving for the indexing to finish? Are you sure it has finished before you close DPL?

I have read someone saying that it can take longer than a day

Yep, when I select the folder which containts all my files it takes a night and day to complete indexing.

I’ve waited until the progress bar disappeared and there was no more message about the indexing still running when I tried to exit DPL.

Have you ever looked at the RAM usage while the indexing was running?

Never looked

So, where are your RAW files? Built-in drive or external storage (NAS)?

I’m still wondering where DPL and ON1 store their catalogs and thumbnails. Lightroom puts them into my home directory on a fast built-in SSD.

They are on the built in drive on the imac and the folder structure is


  • Derivatives
  • Originals
    - Year


So, the question remains where ON1 and DPL store their indexes or catalogs.

I do not know where the indexing is stored. The database on a Mac is stored at: /Users//Library/

In Windows you can customize where the DB and Cache are stored.
I have put it on internal SSD
My biggest folders are 500 pictures in one folder
And yes it could be faster, bat if it’s indexed it’s ok
8 year old i7, 32 GB Windows 10 64bit 20H2
developing 20 files with performance setting 6 files simultaneously DXO needs about 21 GB of the 32 GB
my .orf files are 13 to 20 GB

give it a try and check the settings

best regards


No such settings in the Preferences window of the Mac version. Only the cache size.