How to Open Raw Images in Gimp (RawTherapee & Darktable)

How to Open Raw Images in Gimp (RawTherapee & Darktable)

GIMP is a free photo editing program similar to Adobe Photoshop. It is easy to use. You may wonder why you are using a paid program when GIMP gives you all you need.

But one major limitation of GIMP is the inability to open Raw images. In this article, we will show you how to open Raw images in GIMP using a plug-in called RawTherapee. We will also look at alternative ways to open these files using another free photo editing program, Darktable.

What is GIMP?
Let’s start with a quick overview of GIMP. GIMP is an open-source photo editing program. This means it is free. It also means developers around the world are continually updating it. The program is available for Windows, IOS, and Linux systems. For this article, I used the IOS version 2.10.22. I also used the Windows 2.10.24 version for comparison.

The interface is less polished than a program like Adobe Photoshop. But the workspace layout will feel familiar to Photoshop users.

Photo editing tools are in the upper left-hand corner. Click on a tool to expand your options. Many of these tools are similar to those found in Photoshop. The right-hand column includes brush characteristics and a Layers panel. Many popular Photoshop adjustments and filters are in the drop-down menus. Once you get used to it, you will find GIMP a powerful photo editing program.

GIMP opens many types of files including TIFF, PSD, PNG, JPEG. But the program does not open Raw file-formats, including DNG files, though it will open HEIC files created by your iPhone.

What is a Raw Image?
A Raw image is an uncompressed photo. It includes all the information your sensor collected from a scene. This includes colour and light information.

Many cameras let you take both Raw and JPEG images. When you shoot in JPEG, your camera processes the information hitting the sensor. It keeps some of the information and throws the rest away. You will not be able to get this information back. Many photographers shoot in Raw so that they have access to all the information collected by their cameras.

Each camera company has its own Raw format. The files have different suffixes:

Sony .ARW
Nikon .NEF
Canon .CR2 or .CR3

DNG is a universal raw image format created by Adobe. It is used by many devices, including some smartphone apps. A Canon camera cannot open a Nikon file. But neither can most photo editing programs. They need a converter.

Adobe Photoshop uses Adobe Camera Raw to convert Raw photos into a format that Photoshop can read. If you try to open a Raw file directly in Photoshop, you will first go through Camera Raw. Lightroom can read Raw photo files. When you send a file to Photoshop from Lightroom, the image is already in a format that Photoshop can read.

Just like Photoshop, GIMP needs a converter program to read Raw. There are a few options. Let’s start by looking at the RawTherapee. This program functions as a plug-in for GIMP and functions like Adobe Camera Raw.

How to Open Raw Files in GIMP Using RawTherapee
RawTherapee is free software that reads Raw files. It is a stand-alone program, or you can use it as a plug-in with GIMP. It is available for Linus, IOS, or Windows. You can use RawTherapee to open Raw files in GIMP.

Step 1: Download GIMP
Download GIMP. Choose your operating system and download the program directly to your computer. Follow the installation instructions for your operating system.

Step 2: Download RawTherapee
Download RawTherapee. Follow the installation instructions for your operating system. For this article, I used the IOS RawTherapee version 5.8.

Initially, my Mac blocked installation. Drag the program into your applications file before opening it. If you have problems installing the program, find more installation instructions here.

Step 3: Open a Raw File
In RawTherapee’s File Browser window, navigate to the Raw file you want to open. Double click on the file.

This will open the file in RawTherapee’s photo editor. The workspace is laid out in columns, much like Lightroom. In the left-hand column is a histogram, sizing information, and a history panel. In the right-hand column are panels of sliders controlling image quality. Click the icons across the top to see more photo editing panels. These are Exposure, Detail, Colour, Advanced, Transform, Raw, and Metadata. The controls are not as intuitive as Lightroom, but the general principle is the same. There are more controls above and below the image.

Step 4: Connect RawTherapee to GIMP
The first time you use RawTherapee, you need to set up your preferences to link with GIMP. Click on RawTherapee’s preference icon located in the lower left-hand column. In the preference window, scroll to the bottom and select GIMP as the External Editor.

Click OK.

The Windows version of the program looks slightly different and asks for a directory location.

If the GIMP option does not export your photo into GIMP in Step 5, enter the file path in the Custom Command Line. Open the preference window again. Scroll down to External Editor and click the empty box next to the Custom Command Line. If you are using a MAC, type the following: open -a “GIMP-2.10.app”

If you are using a different version of GIMP, copy and paste the file name between the quote marks.

Click OK.

If you are using a Windows computer, navigate to the GIMP program. Right-click on the program and select Properties. Copy the information in the Target window. It should look something like this: C:/ProgramFilesGIMP2bingimp-2.10.exe

Step 5: Open Image in External Editor
Click the Open in External Editor icon found in the control bar under your image (Ctrl or ⌘E). The raw image opens in GIMP. If the image does not open in GIMP, return to Step 4 and enter the file path for GIMP in the Custom Command Line.

Step 6: Open Raw Photos in GIMP
Once you set up the preferences in RawTherapee, you can open files directly from GIMP. In GIMP, open a file by going to the File drop-down menu and selecting File > Open. Navigate to the Raw photo you want to edit.

The file will first open in RawTherapee with a message welcoming you to the RawTherapee plug-in.

Close RawTherapee, and the file will open in GIMP.

You will see a new file next to the original Raw file with a .pp3 suffix.

It takes a few steps to connect GIMP with RawTherapee. But once the programs are connected, the programs work together to open Raw photos.

How to Open Raw Images in GIMP Using Darktable
Darktable is a free photo editing program similar to Adobe Lightroom. It is cross-platform and available for Linus, IOS, or Windows. Like Lightroom, the program reads Raw images that can be opened in GIMP.

There are two ways to open photos in a Raw format in GIMP using Darktable. The first way uses Darktable as a plug-in, much like the RawTherapee process above. The second way lets you send files from Darktable directly to GIMP. The first three steps are the same.

Step 1: Download GIMP
Download GIMP. Choose your operating system and download the program directly to your computer. Follow the installation instructions for your operating system.

Step 2: Download Darktable
Download Darktable. Follow the installation instructions for your operating system. I used Darktable version 3.4.1 for this article.

Step 3: Import File into Darktable
Start by importing a few files into Darktable. Click the Import button in the top left-hand corner of the workspace. Select either an image or folder to import. It does not matter how many files you import. Add at least one file to activate the workspace.

The basic layout will be familiar to Lightroom users. You edit photos in the Darkroom module. Like Lightroom, changes are made using sliders.

Step 4: Open Raw File in GIMP
Open GIMP. Go to the File drop-down menu and select File > Open (Ctrl or ⌘E), and navigate to the Raw file you want to open. Like the Adobe products, GIMP and Darktable talk to each other.

From here, the process is similar to RawTherapee. The Raw file opens first in Darktable, where you can make basic edits. When you close Darktable, the Raw file opens in GIMP for further editing. If the file does not automatically open, double click on the Raw file again.

Step 4 (Alternative): Export Raw files from Darkroom to GIMP
A script in Darktable called GIMP allows you to Export files from Darktable to GIMP. Unfortunately, the script is unstable and does not always work.

Open the lua scripts installer located in the left-hand column of the Lighttable module. Click the Execute button. You may need to first install Git scripts.

Scroll until you find the GIMP script. At first, it may be labelled ‘gimp stopped’. Click it to turn it on.

In the Export Selected panel, you now should have a new option: Edit with GIMP. Change the file format to TIFF and 32 bit.

Select an image and click the Export button.

When you close GIMP, the image should roundtrip back to Darktable.

This option is ideal for round-tripping images between Darktable and GIMP. But the process was inconsistent. I could send Raw images on my Mac from Darktable to GIMP. But I was not able to get the roundtrip feature to work. On Windows, I had problems exporting Raw images to GIMP.

Conclusion
GIMP is a powerful but free photo editing program. To open Raw camera files in GIMP, use a plug-in like RawTherapee. Once you connect the plug-in, you can open files in GIMP through the plug-in.

Darktable, another free photo editing program like Lightroom, also lets you open Raw camera files in GIMP. This process requires less set-up than using a plug-in. You can either open a Raw file directly from GIMP or export files from Darktable into GIMP.

Photographers do not have to sacrifice image quality when using free photo editing programs. GIMP and Darktable let you process Raw images much like the Adobe products.

Still using Lightroom for your editing? Try out our Effortless Editing course to master all its secrets!