Ceci est une ancienne révision du document !
Website: https://rawtherapee.com/ Price: Free!
Rawtherapee just updated to version 5.8 and this will be the version I am working with. See: https://rawtherapee.com/downloads/5.8/
Though I have not really noticed any difference between version 5.8 and the previous version, there may be some small changes, so if you are not on version5.8 and notice something, just move on or find the setting in your version. (However, the capture sharpening tool will not be in the older versions). That is the best way to learn. The learning curve for Rawtherapee is not as steep as some of the other editors.
Today, I want to take a simple picture and create a sort of stock photo from it. I want to make a wallpaper for two monitors, or one ultra-wide monitor. I am sure you have seen the windows-7 or windows-8 wallpaper of a building façade and I was hoping to make my own for Ubuntu. You may want to do this with something containing a repeating pattern, like bricks in a wall. Do not let me stop your creativity. Any pictures we edit from now on will be hosted on the FCM website, so be sure to visit the website and grab a copy if you would like to follow along - or use your own picture. This was one of those moments where my camera was at home, but I realised that I was carrying a camera in my pocket. I cannot vouch for said camera, as it is on a company stand-by mobile phone (I do not own a cellphone and I am not in the market for one), but it is new-ish and should take a semi-decent picture.
One of the features that I like about Rawtherapee is that you can get an idea of what is happening, color-wise on your photograph. If you move your mouse over your image in the editing window, you will see a crosshair. Now, if you shift your gaze to your histogram, you may notice that your histogram is lifted a few millimetres, and there are three coloured lines below the line. When you move your mouse, you should see the lines move left or right. This is a great indication of where the red, green and blue for your chosen spot is on the histogram. I find this very handy to distinguish where my colors separate. I know that you get percentages in the navigator window, as you move your mouse, but I prefer to see it move horizontally and get the visual highs and lows bringing the two together in my mind’s eye. I say mind’s eye, as I am already imagining where I want to go with my picture. Now, in the picture that I am using, I have a lot of different whites and blues. My histogram does not squish up against any of the sides, (yes, this is a technical term… Hahahaha) so there is no need to turn on clipping indicators. Do you remember the shortcut keys?? They are ‘<’ and ‘>’ . Now, if I move my mouse down the side of the building, keeping to the white(-ish) parts, I can see how the white travels along my histogram as it goes further into the distance. This is something I will have to keep in mind when editing. Any edits to this white also differ from the whites in the clouds.
To illustrate what I am talking about, I want you to go to the RAW tab, bonus points if you know which one it is without hovering your mouse over it, and extra credit if you used the shortcut keys. The second entry should be RAW white points. I want you to grab the slider and move it to the right, increasing the white point. Now you can turn on your clipping indicators and you can immediately see when you have gone too far. Don’t worry, you can click the reset button at any time to undo what you have done. It is the little reverse arrow next to the slider on the right. What you may not have noticed immediately, is that the white point also affects other colours in your photograph, so be aware of that. In my picture, I am not too worried as I plan on cropping it to give me a contrast between blue and white. Clipping means loss of detail, so we want to avoid it unless the area in which we lose the detail is tiny or not important. What I mean by this is that you may have taken a picture to capture corpuscular rays. You stand in the shade and you take a picture into the rising / setting sun – that is behind a tree. The tree moved and you got some sun in. The sun is a blinding white spot and we will be cutting it out of the final picture, so it does not matter if we get clipping there.
The reason I am talking about this is, it is becoming winter now and lots of people are going to be taking pictures in or of the snow. Also, this is the tab that you will see, right at the bottom, the new addition to Rawtherapee version 5.8. The capture sharpening block. We will look at this feature in a future article, but, for now, I want you to note where it is. Today we will get our exposure sorted. As you may have noticed, my histogram has a long straight line on the left. It is not too surprising as there is very little shadow or dark spots in the photograph. Open the exposure tab and we increase our black to where it starts clipping and go two back (2900 by my reckoning). Though I will probably be cutting out the parts where the black is clipping, let us avoid that. I usually aim for less is more, but sometimes the cowboy approach is good for visually stunning pieces.
This is the area I am interested in (more-or-less), but I do not want to crop it yet. Cropping is one of the last steps. Another nifty feature is, that if you went full cowboy and raised your black above that (my) margin, you can mitigate the clipping by using shadow compression. Since my vision for this picture is minimal colors (white, grey, blue), I am going to focus on only saturation and contrast. It is a lot easier to edit when you know what you want out of your picture. If you are not quite sure, it is also good, as you get to fiddle with “all the knobs”, and that way you learn too! Remember to zoom in often, even if you have a high dpi monitor. You may find that you have clipping that you do not see on your zoomed out overview.
TIP: Adding contrast and saturation to your image, may make it pop, but it also introduces grain. You need to walk the fine line here.
Now to change what we perceive. Go to the shadows and highlights block and turn it on. I want to bring my “shadows” up just a little. You will notice that the histogram is compressed a little and moved slightly to the right. Not too much, as you will start washing out the blue. I just want to play with the grey. Then, lastly, I will head down to L*a*b adjustments and play with chromaticity to make my blue pop before finally cropping it.
I now simply throw it into GIMP with ‘crtl+e’ and export it as a jpeg and it is ready for my wallpaper.
So now I have my “stock” photo that I will use as wallpaper on an extra wide monitor, or split across two monitors. Next month we can look at more fun ways to use Rawtherapee, maybe even change this picture into something more… who knows?
Obviously there is more we can do when editing, but this was simply to illustrate how to use Rawtherapee to quickly get what you want. I hope this was informative and as always, should you have questions or comments, please email us on: misc@fullcirclemagazine.org