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5 best features of the Dolphin file manager

by Martin de Boer
5 best features of the Dolphin file manager

I like Dolphin, the default KDE file manager, a lot. I have used it for over 9 years. There are many features that I use regularly that I wouldn’t want to live without. In this post, I like to share my personal top 5. Some features are more obvious, others are hidden features.

1) Split windows

The split window view can be opened with the F3 key or by clicking on the Split icon. This is great for copying files from one location to another. Just drag and drop the files from left to right (or vis versa).

2) Integrated terminal

The build-in terminal can be opened by pressing the F4 key or by clicking on Control –> Panels –> Terminal. This is handy for the few Linux applications that need to be downloaded from an external website. For example: Oneplay Codec pack and Codeweavers Crossover Linux. The terminal automatically opens in the location that your are visiting, allowing you to directly input the zypper cli commands.

3) Show hidden files

Sometimes you want to edit or remove a configuration file. These files are often located in hidden folders in your Home directory. By showing the hidden files, you are able to navigate to these locations with ease.

4) Open With

The ability to open a file with the application of your choice is very handy. I like to open images with Gwenview by default. But for editing, I like to open them with Kolourpaint or GIMP. This feature allows me to do this with minimal effort.

5) Previews

You would think that this feature would be nr. 1. But unfortunately Preview didn’t always work as advertised. This was mainly a problem during the Qt 4 days (2009 – 2014). The Preview function is working without issues since the Qt 5 version of Dolphin. You can enable previews by clicking on the associated button. You can use the slider in the bottom right, to increase or decrease the size of the previews.

Published on: 21 October 2018

Basic photo editing with Darktable

by Martin de Boer

When I was starting in the world of amateur digital photography, I learned about 2 software programs that everybody was using: Adobe Photoshop and Adobe Lightroom. In the Free and Open Source world, there are 2 amazing alternatives: GIMP and Darktable. GIMP is aimed at destructive (the image is changed when saved) photo editing. It can be used to change photos in many ways, including cutting things out of the picture or pasting things into the picture. Darktable is aimed at non-destructive photo editing. I like to compare it to developing a photo. The negative is kept, and the photo (the positive) is developed from the negative. For many people, getting started can be daunting. Therefore I like to present the absolute basics of photo editing with Darktable.


First open Darktable. When the program is opened, you need to load a photo collection. You can do this for many photos at once by clicking on ‘folder’ in the left sidebar in the ‘import’ section.

Select the folder in which you have stored the RAW files of your digital camera. Click on open.

Note: If you only take JPG pictures with your digital camera, Darktable is not for you! You should look into GIMP.

Now your photos will load in the Lighttable section of Darktable. In the top right of the program, you can see (highlighted) in which section of Darktable you are currently working. To start editing a photo, double click on the image.

Now you are automatically moved into the darkroom section of Darktable. Underneath the sections you see a Histogram (the colored chart) and below that a row of buttons. These buttons are the groups in which the functions of Darktable are grouped. Now click on the ‘basic group’ button. Then click on ‘white balance’.

The easiest way to get the white balance right is to find a white spot on your photo and select this. To be able to do this, you first need to go into the white balance presents and change this from ‘camera’ to ‘spot’.

Now you can zoom into the photo by using the mouse wheel (if you have one) or by using the navigation functions (located in the top of the left sidebar). Then select the part of the picture that represents pure white and Darktable will automatically determine the white balance. When I am not 100% happy with the result, I simply try again on another spot.

You can also use one of the presets that are available by default such as: camera, daylight, shade, cloudy or flash. Or you can manually drag the temperature left-right to select the white balance that you prefer.

After having selected the right white balance, it is time to get the light/dark area’s of your photo right. Go into the tone group. Now select levels.

What you want to do, is look at the histogram and see where it drops off. Most histograms look like a mountain range with an upward slope on the left, a middle part that’s like a mountain range and a downward slope on the right. If you don’t see a slope on the left, that means that your dark areas are fine. If you don’t see a slope on the right, that means that your light area’s are fine. What you want to do, is to drag the line on the left or on the right towards the middle, so that the slopes are shorter or even gone. Try to experiment with this!

The last group in this tutorial is the correction group. Select the lens correction.

Now you want to enable the lens correction with the ‘on’ button of the module. In most cases, the camera and lens are already selected correctly by Darktable. Otherwise adjust the camera model and lens to the ones that you have used.

The only thing remaining is to export the photo(s) into the JPG format. Click on lighttable, to change the Darktable mode. Then in the right sidebar go to the ‘export selected’ part and click on the folder icon to select the folder where you want the pictures to be saved. Now select all the images that you want to export (in the middle section) and then click on the export button.


Using Darktable is not as difficult as it might seem. You just need to know your way around. There are a lot more functions available. But the ones in this tutorial are enough in 95% of the time. In future blog posts, I will explore some of the more advanced features.

Published on: 15 October 2018