# Intro to Lightzone by Seth Kenlon In the previous two months, we've looked at Darktable and Digikam as open source photo management and editing suites. A third open source photographer's suite, called LightZone, has been around since 2005 as a closed source application, but got open sourced when its parent company dissolved in 2011. As a result, LightZone is now an open source and no-cost software for high end photo editing and management. It's written mostly in Java, although it uses some external libraries for certain image formats; even so, it's ardently cross-platform, and very powerful. ## Java Dependencies Being based mostly on Java, LightZone assumes a fairly robust Java environment. It's becoming rare for an OS to pre-install Java, so if you don't use many Java applications on your system, you may not have all the Java packages LightZone expects to find. It's down to what Java kit you do install, so for the quickest and easiest results, you can install [the full JDK](http://www.oracle.com/technetwork/java/javase/downloads). That should have everything you need. If you prefer to micro-manage, you can install [OpenJDK](http://openjdk.java.net) or, if you prefer,[IcedTea](http://openjdk.java.net/projects/icedtea) but if you take this route, some extra Java classes may end up being be required. If you try to launch LightZone and it complains about missing Java classes, search for the error online and install the Java component that is said to resolve the missing class. I only encountered errors when installing Java piecemeal; specifically, I hit a `java.lang.NoClassDefFoundError: javax/help/HelpSetException` error that seems to be fairly common, but an online search and an install of the `javahelp2` package fixed the issue. ## Installing LightZone LightZone can be downloaded from [lightzoneproject.org](http://lightzoneproject.org), although you must register with the website before reaching a download link. On Linux, you can install LightZone in two different ways. You can either install it to your filesystem using [checkinstall](http://asic-linux.com.mx/~izto/checkinstall/) or you can just run it from your user directory. To install with checkinstall: $ mkdir lightzone-4.1.1 $ tar xvf lightzone*4*xz -C lightzone-4.1.1 $ cd lightzone-4.1.1 $ sudo checkinstall This builds and installs a `.deb`, `.rpm`, or `.tgz` package (depending on what's appropriate for your distribution). You can manage the package as usual using your system's packaging tools (dpkg, rpm, pkgtools). To run from a local directory: $ mkdir -p $HOME/bin/lightzone4 $ tar xvf lightzone*4*xz -C lightzone4 $ cd lightzone4 $ sed -i 's|usrdir=/usr|usrdir=$HOME/bin/lightzone4/usr|' ./usr/bin/lightzone $ ln $HOME/bin/lightzone/usr/bin/lightzone4 -s $HOME/bin/lightzone To launch from the local directory, run `$HOME/bin/lightzone` from a shell, or modify the `lightzone.desktop` file to run that command for you. ## LightZone Basics LightZone, like Darktable and a few closed source competitors, is designed to be a photography *workflow* application. LightZone is not trying to replace a photo compositor like GIMP; it's trying to make your photos easy to find, sort, and re-touch. An ideal user is anyone who takes lots of photos (like a wedding photographer, a studio photographer, or any average tourist with a cell phone) and has the need to ingest hundreds or thousands of shots, sort through 5 or 10 versions of essentially the same subject, choose the best one of the bunch, touch up any imperfections, and publish the results. When you first launch LightZone, it starts in **Browse** mode. At first, your workspace is empty, so you can choose a folder containing images from the file tree on the left. The moment you select a directory with images in it, the images are loaded into the LightZone browser: thumbnails on the bottom third of the window, large preview on top. ![Lightzone browse mode](browse.jpg) To view and work on RAW photos, you must have DCRaw libraries installed (just as for TIFF support, you need tiff libraries, and so on). The thumbnail browser at the bottom of the window provides most of the functions you'd expect from a photo thumbnail viewer. Using the browser toolbar, you can adjust thumbnail size, rotate images, sort by file name, file size, or even metadata such as your own rating, capture time, focal length or aperture setting. Right-clicking on any thumbnail reveals even more actions, including the ability to rename, convert, and print the image. A single-click on any thumbnail makes it the active salection. A control-click on two images brings both images up in the viewer, side by side, for easy comparison. You can view several images in your browser at a time (up to five on my display; after that, you may as well just adjust the size of the thumbnails and view the photos that way). Each preview image that appears in the top panel has a `Edit` button overlaid in the bottom right corner. To edit an image, click `Edit` on the photo, or click the `Edit` button in the upper left hand corner of the LightZone window to bring the active selection into the edit view. ## Edit In the edit (what you might think of as the "digital darkroom") view, there are three main areas of interest: 1. The left and right side panels hold presets and filter palettes. These are what you'll use to apply effects to your photograph. 2. The upper right corner provides an informational window, with details about zones and colour values. 3. The center panel displays your image. If you feel you need more room to work, hide panels using the vertical tabs on the left and right of the LightZone window. Your workflow will probably start with the panel on the right. Underneath the **Zones** panel, there is a horizontal list of available filters. Any filter placed on a photograph appears in the filter stack underneath the filter list. ### Filters The filters in LightZone are, to me, a perfect mix of simple but must-have effects similar to those found in Digikam and Darktable, plus a few surprisingly powerful tools rivaling functions found in the likes of GIMP. For the former group, LightZone offers a zone mapper (like a **levels** filter, but from a more Ansel Adams perspective), hue and saturation control, sharpen and blur, white balance, colour balance, and noise reduction. Each filter has a well-documented entry in LightZone's inbuilt user guide, and since they're non-destructive, you can try them without actually affecting your original photo. Something that sets LightZone apart is that each of those "standard" filters also has a selection- and colour- based constraint system, so any filter you apply can be done on only *part* of your image. Other applications can do that, but the fact that LightZone builds the option in on *every* default is a real time-saving convenience. ![LightZone Filters](filters.jpg) Another little surprise that LightZone ships with is the clone filter. By default, the clone filter clones an image and overlays it onto itself. This is great for some very interesting compositing effects, but it's even *better* once you clone parts of an image. Now you're compositing, just as you might in GIMP. ### Presets Each filter can have a preset: a temporary snapshot of a setting that you want to keep on hand. It's sort of a reverse-undo function; if you adjust a filter and get a result that you like, then right-click on the filter icon in the filter's toolbar and select **Remember Asset**. Then, imagine that you adjust the filter again but end up with something less appealing that you had before. You want to undo your changes, but you've been through a few iterations of each slider in the filter, so what would you undo? Of course, you wouldn't; instead, right-click on the filter icon in the filter's toolbar and select **Apply Preset** and all of your settings are set back to when you took the preset snapshot. ### Styles More complex than filters, and far more permanent, are **Style**. While a preset lasts for only as long until you overwrite it with a more recent snapshot, a style gets saved to your LightZone configuration forever. Styles are also broader in scope; instead of just taking a snapshot of one filter's settings, a style can contain a whole stack of filters. Preset styles are available in the left side panel. If it's not visible, click the **Styles** vertical tab to reveal it. Hovering over a style displays your photo in the upper left corner, with that filter applied. Double click the style name to apply the filters it contains to your photograph. Be warned, this *adds filters to any filters you have already applied* up to this point, so be sure to start with a clean slate if you want to see just the style's effect. ![LightZone Styles](styles.jpg) Any combination of filters can be saved as a Style with the **Add a new Style** button at the top of the window. By default, this gathers all current filters and settings from your currently active image and wraps them in a style. ## Compare the Contrast To "flip back" to your original image as you edit, click and hold the **Orig** button in the top toolbar. Release to get back to your edit in progress. ## History The history palette on the left is an undo stack that persists while you work. When you leave **Edit** mode, your history goes away. ![History](history.jpg) ## Saving Images To save an image, click the **Done** button in the top toolbar. This option *never* overwrites your original photo; it saves a new version, differentiated by inserting **lvn** in the filename. The format that LightZone saves to is determined by your LightZone preferences. ## Preferences Go to the **Edit** menu and select **Preferences** to configure LightZone's default behaviour. There are three tabs in the Preferences window: * General: set how much RAM LightZone can use, the location of its scratch folder, the colour profile of your display, and more. * Save: default file format of saved (exported) images and associated options (compression levels, bit depth, ppi, and so on). * Copyright: the copyright and copyleft message to embed into exported images. ![Preferences](prefs.jpg) ## LightZone LightZone is a capable and "prosumer"-level application. It's not quite as feature-rich as DarkTable or Digikam, but it's not quite as simple as not as simplistic as something like [FSpot](http://f-spot.org). Being Java-based, it's easy to install on all platform, ensuring a consistent workflow across all users. And the results speak for themselves. Try it out!