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Stikkord: photo editing

  • What’s new in Darktable 2.6

    What’s new in Darktable 2.6

    Like the last few Christmases have done, this one too gave us a brand new version of my favourite image processing software, Darktable. This time we got a whole lot of new toys to play with. A whopping three new modules, significant updates to several others and lots of smaller tweaks all around makes this one a really great release.

    New module: duplicate manager

    We have always had the possibility to make virtual copies of images in Darktable when we wanted different versions. The new module duplicate manager takes this to the next level. Now we can give the different versions names and we can compare edits quickly with a single mouse click.

    New module: filmic

    This is one of the most talked about news. It’s a new approach to shaping the contrast and fitting the relatively high dynamic range of modern cameras into the lower dynamic range of a jpg file, and at the same time mimicing somewhat the image characteristics of film. The author of this module, Aurélien Pierre, has written a long and very good article about this module on his website, which is well worth reading: http://bit.ly/2RXFQue

    New module: retouch

    This is a replacement module for the old spot removal module, with new and advanced tools. Spot removal is still available for compatibility reasons, but it is no longer necessary.

    Where spot removal only used cloning, retouch uses “intelligent” healing by default. Cloning, as well as blur and fill is also available. And where this module really shines is in its ability to work on different detail levels due to frequency separation.

    Updated modules: raw denoise and profiled denoise

    Both these modules have got a graph like the equalizer module, where you can ajust which frequency bands the noise reduction will affect. For profiled denoise this is only with the wavelets mode. This gives greater control over the noise reduction, minimizing unwanted artefacts. Profiled denoise has also got two presets, meant to be used together when you use two instances to separate color noise and luminance noise.

    Updated module: color balance

    The color balance module has been reworked and has got some good additions, making it much easier to use. You can now use two sliders in each of the shadows, midtones and highlight areas to select a hue and adjust the amount without having to balance the R, G and B channels separately. The old method is still available too.

    Updated module: tone curve

    The tone curve module has also got a few nice updates. Linked RGB channels is now the default mode, which for many will be the expected way. The curve graph can be viewed in logarithmic mode, which gives much better control in the low light areas. There is also a selection of three different algorithms to calculate the curve smoothness.

    Updated module: spot removal

    Not much here, but for those who want to continue using spot removal, you can now change the opacity of each shape intividually.

    Updates to parametric masking

    Parametric masks are now even more powerful and easy to make with the new edge aware feathering option. I wasn’t aware of this when I made the video, so I don’t mention it there.

    Other updates

    • You can have scroll bars on the sides of the image when zoomed in. This is available in Preferences.
    • The file type in lighttable view is more visible, as it it displayed vertically for portrait oriented images. It is still hidden for square images, though.
    • An option in Preferences makes it possible to display some EXIF data when you hover over an image in lighttable.
    • Some new sorting options are introduced.
    • I am sure there are things I have not mentioned here. For a complete list of everything new and how to use it, read the blog post on the Darktable website: http://bit.ly/2RSwwrL

    And don’t forget to view my video:

  • Black and White in Darktable

    Black and white is a genre as old as photography itself. Back then it was the only way, if you wanted colours you had to get out your crayons and colour the print. These days we do it the opposite way. We take a colour image and make it black and white.

    Of course black and white means essentially that there’s no colour. But you can’t make a great black and white image by simply turning the saturation to zero. The colours are an important part of a colour image, and if you remove them you will have to compensate with something. And what is left when you take the colours away is contrast. To make a striking black and white image, we often have to increase the contrast, not only for the whole image, but also locally.

    One very useful way of manipulating the contrast of a black and white image is to adjust the brightness of individual colours. In Darktable, we have essentially three tools for this:

    • Channel Mixer: Decide how much each of the red, green and blue channels contribute to the final image.
    • Monochrome: Mimics the way coloured filters are used with black and white film.
    • Color Zones: My favourite. Adjust the brightness of up to seven different colours in the image, and also decide the exact hues to adjust.

    In the video below i explain how to make stunning black and white images in darktable.

  • Sharpening in Darktable

    Sharpening is a very delicate subject. It should be used with great care, and mostly to give a little bit of extra pop to already reasonably sharp images. It may be tempting to oversharpen in order to «fix» bad focus or motion blur from camera shake, but as this would be the same as restoring detail that just isn’t there, it should be avoided.
    There are three ways to apply sharpening in Darktable: Sharpen, Equalizer and the High Pass filter. They work in different ways but the results are very similar. Therefore I don’t want to say anything about when to use which method. You should learn them all and decide for yourself in each situation.
    Also, Sharpening should be done at the very end of your workflow, and ideally you would sharpen for each output resolution. Say you export a small file for Instagram, a medium sized file for a web site and a full size file for printing. If you zoom in to 100% and sharpen the very finest details, this sharpening will never be visible in the Instagram file. Small file sizes require sharpening on a larger scale. And if this sharpening is done in the full size file, it will look more like overdone local contrast than sharpening.
    To learn about the different sharpening tools, watch the video here:

  • Reducing noise in Darktable

    Noise from high ISO can be a pain sometimes. Darktable has several tools to help you get rid of it or at least reducing it. In this week’s video I show you the different tools and how to work with them.

    There are however a couple of things to remember that I did not mention in the video. Noise reduction is very processor intensive and has a tendency to slow down the editing quite a bit, since all the edits are recalculated every time you make an adjustment. Therefore it is important to think about when you apply noise reduction in your workflow.

    If you do it early on you will have a cleaner image to work with. This will make it easier to set up good parametric masks, but Darktable will become slow. If you leave it to the end you may have not so perfect masks, but Darktable is quicker. So it is a balance you have to find for yourself, also taking into account the power of your computer. If you have a beast of a machine you may not notice much difference, so you can have noise reduction early on without problems.

    I tend to do it this way: if it is an easy edit without much work, I just apply the noise reduction early in the workflow and leave it on. If the edit is more complicated, I like to do it quite early and then turn it off, only keeping it on when I set up critical parametric masks. Then I turn it on again before I do final sharpening. If I during the process send the image over to Gimp for some extra work there, then I do noise reduction before the export. In that case I don’t sharpen anything before export, I do that either in Gimp or when I get the image back into Darktable.

  • Colour adjustments in Darktable

    One of the most important aspects of photo editing is to adjust the colour balance. In Darktable there are many ways to do this. Check out my latest video if you want an overview of the different methods.

  • Adjusting tones, part 2

    It’s no good showing things only on custom made test images. We also need real life examples to understand how to apply our new skills to our own images. In todays video I take the things we learned last time and apply them to real images. For example, why is it not a good idea to set the radius in Shadows and Highlights module to zero? It worked like a charm last time on the test image. Check out the video below to find out for yourself.