Last I checked (maybe a year or two ago) Darktable was an integrated photo-management tool for ingesting, sorting, cataloguing and developing RAWs, while RawTherapee was almost entirely built for developing RAWs with just a few management features on the side.
Well, darktable user here (Also a RawTherapee 5.0 user).
I just closed darktable few minutes ago, so I guess that made my experience of it pretty fresh.
On my system (Ubuntu 17.4), darktable runs nicely. And it's easier to use than RawTherapee. I only encountered some problems cause it to freeze up when loading photos, but I can't figure out the reason (Of course it's not because I'm loading photos).
RawTherapee is bit harder / complicate to use, but once you used to it, they're almost the same (Not totally, like darktable's Vibrance adjustment is far weaker than RawTherapee's etc).
One problem with RawTherapee for me is, it sometime can't correctly recognize the color profile of my camera, so the initial preview look over exposed and require manual adjustment. I didn't get same problem with darktable.
In Darktable, applying styles to the light table `Export` module is a way of sending 'prints' to a standard subdirectory structure. Bash scripts calling darktable-cli might be another possibility for automating a similar process at higher volumes.
Having used both Dartable and Rawtherapee, part of the reason I primarily use Darktable is that it seems to better facilitate working through a few hundred images in a few hours...a use case that not everyone has and that some people might reasonably not ever wish to have but one that I deal with based on the type of subjects I sometimes shoot.
A 1-2 hour shoot for me with a model might easily result in 500+ images. But I've found with the rating system of rawtherapee it is easy to process such a large number of images efficiently.
I've tried both a for some time and stuck with Darktable.
* RawTherapee runs on Windows since years.
* Darktable just started the Windows port.
* RawTherapee seems to provide more functions.
* Darktable seems to be better integrated and polished.
* RawTherapee was a bit easier to get into.
* Darktable has a better workflow if you're into it.
* Darktable also seems to be more "stable" in the sense that not everything changes meaning all the time and most things work like expected.
In the end, the workflow was the deciding factor for me. It just felt way better and more efficient. Technologically they are different. RawTherapee should have more potential once they manage to clean up the user interface.
RawTherapee is terrible with DNG files. I have a lot of Olympus E-M1 images that I had Lightroom convert to DNG. DarkTable handles these files just fine. They are unusable in RawTherapee.
The issue is that RawTherapee can only handle Linear DNGs. Linear DNGs are essentially TIFF files where the underlying sensor data has been de-mosaiced and normalized. A Linear DNG retains the higher color depth of the sensor, but it's not RAW.
DarkTable has no such limitation. It properly recognizes the underlying CFA scheme (which are different for different sensors), and processes them properly.
Last I checked (a couple of months ago), DT had a WAY better workflow, and it's better integrated (as mentioned in another comment here).
Also as I've seen mentioned in other comments, it lacks local adjustment tools and/or anything remotely equivalent to the masks system in DT.
It does have some interesting tools, but comparing DT to RT feels like comparing Ps to GIMP... there's a fundamental capability in the workflow that you'll feel missing if coming from DT to RT.
The reason I don't (and wouldn't) use RawTherapee is that it does not have any selection tools that allows you to edit parts of the image (beyond gradients).
What this means is that you set your global contrast and export the file for further dodging/burning and edits in Photoshop, Gimp or some other software.
If you increased the contrast of the image in RawTherapee you will have darkened the shadows. So, when you open the exported bitmap in Photoshop, dodging an eye or some other part in will give you a lot more noise and a lot less headroom compared to doing this work on the undemosaiced data.
This is a big design fail and an actual problem if you go beyond the most basic raw conversion.
My point was that you could probably simply export as 16-bpc TIFF and I'd be surprised if RawTherapee didn't support that (cursory search through the docs suggests that it can do so).
I tried both around a year ago. Darktable was buggier. When darktable was working well enough for a comparison, the out-of-the-box workflow in RawTherapee seemed a lot better to me.
Just like GIMP compares to Photoshop. All the tools are there, maybe there is even more of them. However something feels "off", things sometimes freeze for no apparent reason. The less you know Lightroom the greater the chance that you will like RT
Fortunately for the alternatives that would describe Lightroom these days too, to the point that Adobe had to publicly acknowledge that performance isn’t good enough [1].
The last LR version I used was LR3 and performance was really not a problem. That was 2010, mind you. On an even then outdated dual-core AMD system with the images and the catalogue on some old hard disk.
So, am I correct to understand that Adobe managed to botch LR so badly that PCs with vastly superior processing and IO to what I used back then struggle on basic tasks?
One explanation can be that they managed to botch it the other can be that size of RAW images increased significantly in the meantime. I had no problem running relatively recent LR on i5 with 16gb ram.
(I had problem with their pricing though, so I switched to another (non-OSS) SW that is performing similarly for ~1/3 of the price)
Talking about their licensing practice, I was about to buy a license for LR but their website prohibited me because I'm from their no- support/blacklisted country, so I can't buy. thanks for piracy and FOSS as well.
The image quality and detail level, presumably from the RAW decoder, is pretty poor compared to Lightroom, CaptureOne etc. The last time I gave it a try was about a year ago though.
To me it seems that Lightroom makes it much easier for users to get a decent quality due to a much better polished user interface and sane presets. You should be able to obtain the same quality with both programs but it takes oh-so-much work to get gradients, color, detail, denoise into the right balance.
