Rawtherapee V5.3: The Best Raw Developer?

I first stumbled across Rawtherapee back in 2009. I was trying to switch over to an entirely Linux based photographic workflow like I had already done with my programming work. At that point in time I was using a LightRoom/Photoshop combination on Windows 7 for my photography work and I must say it was quite annoying rebooting my system into different operating systems for different work. I must say, Rawtherapee was love at first sight. Within a matter of months I had replaced the LightRoom with a combination of DigiKam for cataloging, and Rawtherapee for raw image development.

Rawtherapee has a fairly feature rich file brower. It only has basic cataloging features such as ranking by stars and sorting by colors. This is one area where Rawtherapee is lacking but this section of the program is being fleshed out rather quickly by the developer.

Rawtherapee V5.3: File Browser

One of the more interesting features that have been added  recently to the File Browser is Inspect tab. What it does basically is show you a 100% view of the image you have your mouse over. It moves around with the mouse pointer and seems quite quick and responsive. I didn't notice any lag on my older laptop. So I must say that this is a very helpful feature for sorting files quickly such as a portrait session.

Rawtherapee V5.3: Inspect

Once you've picked out the file to edit, just double click on it and it will load it into the Image editor. The image editor can be a little intimidating to beginners just due to the sheer amount of options available.
Here's a short list of editing features:

• Full exposure control
• Highlight Reconstruction
• Tone Mapping
• Vignette Filter 
• Graduated Filter 
• Sharpening
• Noise removal (Multiple Methods)
• Lens Correction (Automatic and Manual through LensFun)
• Lot's of color correction features
• Film Simulation (When HaldCLUTs are downloaded) 
• Demosaicing algorithm selection  
• And many many more. 

For a complete feature list please click this link!

(It's to their official feature list)

I'm just going to talk about the most important features to me personally. For my style of editing I normal just correct white balance, exposure, use the curves for contrast, lens distortion correction, and then apply a film simulation profile and depending on the image maybe a slight vignette. 

Rawtherapee V5.3: Editor (with Neutral Profile; no adjustments made)

Here's what I did to the about image.

• Set White balance with Dropper
• Applied Highlight Reconstruction
• Used Curves to add Contrast
• Fine Tuned Exposure
• Applied a Kodak Portra 160VC Film Simulation
• Applied automatic lens distortion removal 
• Removed Chromatic noise
• Applied a slight vignette 

Rawtherapee V5.3: Image after editing

The color on this particular image is mixed from three sources (florescent, tungsten, and daylight) so it was a bit troublesome getting perfect, but as you can see the image is quite a bit better.

I'd like to talk now about some of the more specialized features of Rawtherapee, in particular the Demosaicing Algorithms. Rawtherapee offers a lot of different options on this front; some more useful than others. 

• AMaZE
• IGV
• LMMSE
• EAHD
• HPHD
• VNG4
• DCB
• AHD
• Fast
• Mono
• None
• Pixel Shift

As you see there's quite a few different options to chose from and your choice actually makes a big difference! I'm only going over the ones I personally find useful and to deliver the best quality. I'm an Olympus shooter, so you mileage might vary with my recommendations. 

I find that in general for modern Olympus cameras the AMaZE algorithm gives the sharpest and cleanest results at low to medium ISO's (I.E. 100-1600). After this, if can introduce some odd artifacts. It creates tiny little 2-3 pixel long bars in the noise pattern. This is an issue AMaZE used to have really bad before they updated the algorithm. At lower ISO's this algorithm gives astounding results. They're extremely sharp and have a naturalistic grain rendering. It's the sharpest demosaicing algorithm I've ever seen and easily bests Adobe's in sharpness and noise rendering. 

If I'm developing high ISO images, I tend to hop between IGV and LMMSE. These are both designed to minimize noise and to render the noise in such a manner where it's easier to remove it using the included noise removal options. I personal loath noise removal, but I find the way IGV and LMMSE renders the noise to be reminiscent of highly pushed black and white film. It's in no way identical, it just reminds me of that for some reason. 

VNG4 is an old demosaicing algorithm. It's been around for as long as I can remember at least. It's only useful nowadays because it produces next to no artifacts, but that comes at the cost of both sharpness and of noise rendition. I still use it on an occasion for files from older odd cameras such as the Sony F-828 camera which had a RGBE filter instead of the traditional Bayer filter layout. I used to own one of these back in the mid 2000's and will find a file from it I never got around to processing. 

There's also some odder options such as None which doesn't apply any demosaicing whatsoever. From what RawPedia had to say on it's uses, it's for diagnostic purposes. I'm afraid to say that what those diagnostic purposes are is way above my pay grade. 

Union Covered Bridge, MO, Olympus OMD-EM1, Olympus M.Zuiko 17mm F1.8

Demosaicing Algorithm Examples

I'd recommend downloading the crops file and zooming in to maybe 300% to 400% and looking at the grain patterns. They're all remarkably different.

Pardon this awful photo. It's the only High ISO example I had handy on my laptop at the time of writing this.

Notice how smudged the noise looks in VNG4 compared to the rest.

Conclusion:

Overall Rawtherapee is a feature rich program that offers some of the highest quality output on the market (both free and paid). It has a slight learning curve only due to the sheer amount of options it offers. I personally would consider Rawtherapee more of an Editor then a full blown cataloging programming. One of it's biggest weaknesses is lack of keywording in the file browser. Even taking that into consideration I feel that it's one of the strongest editors on the market right now. It offers the highest quality output of any developer I've used and has the customization to make the images output truly yours.

I didn't get a chance the cover all of the features in this post. I'll go through more of the features in a later post. For example the Film Simulation part of the program for sure deserves it's own post. So does the wavelet tool. I've barely scrapped the surface of the program here and I for sure need to write more on this brilliant little program! Look forward to more posts on Rawtherapee and Photography in general.

Thanks for reading!
--Given Zane
Instagram: @GivenZane
Flickr: www.flickr.com/photos/givenzane/



Test Machine Specifications:
Operating System: Linux Mint 18 'Sarah'
CPU: AMD A8-5557M
Memory: 4BG
Display Resolution: 1280x720