Understanding Used Space, Free Space, Snapshots, and Compression on ZFS Datasets
Understanding how much space a ZFS dataset is using is not as straightforward as it first seems, but let's dive in and decipher how to calculate used space on ZFS.
Articles
Understanding Disk Caches, The Journal, Barriers, and Writeback Using QEMU/KVM and EXT4
There are multiple layers of caching involved when writing a file before it makes it to permanent storage on your disk. This becomes even more complicated with a virtual machine which has its own set of caches. Let's explore how exactly writes make it safely to your disk, both on a physical server and a VM.
Effortlessly Make Targeted Color Adjustments With Color Equalizer
The new color equalizer module in darktable 4.8 brings an easy, scene-referred approach to targeted color adjustments using familiar hue, saturation, and lightness/brightness tabs.
Create Focus In A Busy Scene With Selective Color
Sometimes a composition is quite busy and it's hard to isolate focus on the main subject. Using selective color to make the subject stand out can not only quiet down the image but also add add an element of contrast to the scene. Let's look at several examples.
One Deep River
Filled with trains and deeply introspective, Mark Knopfler's new album, One Deep River, delivers another collection of songs in his wonderful, distinctive style. While there aren't as many stand-out tracks for me as Down The Road Whenever, the following highlights flow perfectly with his existing catalog.
Understanding ZFS Snapshots and Harnessing Their Power With Sanoid and Syncoid
ZFS snapshots are an incredible feature to easily take backups, protect against accidental deletion, and understand how your data is changing over time. Let's review how they work and how to harness their power with ease using sanoid and syncoid.
Artistically Blending Colors Into A Scene
Maybe you just missed the peak colors of a sunset, or maybe you just want to apply an artistic interpretation to a photo. Darktable offers powerful and easy-to-use tools for blending new colors into a scene; let's take a closer look at some different techniques for how to do this.
Understanding Free Space, Reserved Blocks, and Inodes on The Ext4 Filesystem
When using the ext4 filesystem, have you ever encountered a situation where free space ran very low on your system, yet processes didn't crash? Let's explore the built-in safety mechanism ext4 uses to keep your system safe from a runaway process consuming disk space.
Adjusting The Shadows and Highlights Using Tone Equalizer
It's hard to overstate the power of the tone equalizer module in darktable: it can perform tone adjustments on the whole image or only a certain luminance range and preserve details throughout the process. This module has a lot of options, which can seem intimidating at first (especially if coming from Adobe Lightroom), so let's look at several example images to see how to use it.
Ubiquitous JPEGs Have Conditioned Us To Think Hue Shifts Are Normal
At first glance, the flower above might look fine. However, there is a hue shift going on which makes the flower look green/yellow even though it should be an orange/yellow. This phenomenon is present on a huge number of the JPEGs generated on-the-fly (also know as out-of-camera JPEGs) from smartphones and other devices.
Understanding ZFS Datasets
ZFS datasets are a powerful and flexible organizational tool that let you easily and quickly structure your data, monitor size over time, and take backups. Learn more about how to create and manage ZFS datasets in this article.
Changing Colors in a Scene
When developing a photo, you may want to change the color of an object or set of objects in a scene while not altering other parts of the image. In this example, the autumn colors were just starting to change but would have appeared much more dramatic a week or two later. Let's show how we can use darktable with a couple of different methods to shift the scene to this later, more dramatic time period.
Reflections on Reflections and The Value of Circular Polarizers
Using a circular polarizer and knowing how to selectively enhance contrast with the local contrast module can make reflections stand out and give an image a much more dramatic look.
The Unlikely Story of Michael Garibaldi
Against all odds, the story of Michael Garibaldi is one of hope and the possibility of happy endings. Although he may be most easily recognized for his role as Chief of Security, his friendship with Jeffrey Sinclair, or his great sense of humor (fasten-zip, peekaboo, etc), in fact his biggest lesson is to never give up trying for a better tomorrow. As we celebrate Babylon 5's 30th anniversary, let's explore what makes Mr. Garibaldi such a compelling character.
Star Trek: Picard Series Review
Star Trek: Picard ended its third and final season recently with a phenomenal conclusion that explored powerful themes and reaffirmed that the core values and ideas of Star Trek are once again present in modern Star Trek. Let's review each season and cover the major themes.
Getting Started With Photography Gear
Getting started with digital photography can seem intimidating because of the price of cameras, lenses, and accessories. Moreover, the myriad of choices of brands adds to the complexity. Fortunately, there is a surprisingly simple solution to getting started.
Sigmoid Makes Dramatic Black and White Simple
The new sigmoid module in darktable 4.2 makes it easy to create dramatic black and white compositions. While there are many ways to achieve this effect in darktable, sigmoid makes it fast and easy.
Reducing Chroma Noise in Water
Review multiple techniques for reducing chroma noise in the water of seascape scenes.
Return of the Dream Canteen
Fans of the Red Hot Chili Peppers are graced with not one but two beautiful, rich albums in 2022 with the return of John Frusciante (and Rick Rubin). The overall theme I see in this new album is everyone performing at the top of their game. As is often the case with RHCP, the magic of these 4 musicians working together results in something incredible and greater than the sum of its parts. Read on for a full review of the album.
You Should Be Watching The Orville
The Orville, Seth MacFarlane's homage to Star Trek: The Next Generation, is a phenomenal scifi show and I would highly recommend you check it out on Disney+. I'll outline some of the reasons why this show stands out below.
Elevate Your Note-Taking with Obsidian
Finding a way to effortlessly take notes across different devices and easily apply formatting is something I've been searching for for a long time. Solutions like Dokuwiki or even Google Docs don't allow for easily and intuitively adding markup to a document, particularly when on on a mobile device. Moreover, keeping notes organized in a simple folder structure is important for interoperability with other apps and services. Enter Obsidian, a phenomenal note-taking app that allows you to effortlessly write notes, add markup using Markdown, and sync across devices.
Using OpenCL with Darktable and ROCm on Arch Linux
Learn how to use OpenCL with darktable for improved performance using ROCm on Arch Linux
Selective White Balance on Part of a Photo
Adjusting the white balance of a photo is a fundamental skill needed when developing RAW files. In this tutorial, we take it a step further and show how to use darktable's powerful selective white balance to use different white balance settings on specific parts of the image. Typically, this would be used to correct the color from multiple light sources (each with different color temperatures), but in this case we'll use it to keep the subject neutral while adding a creative effect to the background.
Highlighting The Subject Using RGB Channels
Mastering the channel mixer allows you to not only adjust white balance, but also creatively color grade a photo to set the mood, change the luminosity, and make local adjustments to specific areas of the photo. In this example, we use color calibration to highlight a subject when the surrounding content, in this case the green foliage, is naturally brighter than the subject and thus pulls your focus away. We can counteract this using channel mixer in color calibration.
The Case For Q
With the season finale of Star Trek: Picard, we finally learn if Q is a friend or a foe. Let's review the case for Q as a friend of Jean Luc Picard, and reflect on John DeLancie's phenomenal performance in Farewell.
Unlimited Love
I've been eagerly awaiting the release of the new Red Hot Chili Peppers album for quite awhile, and Unlimited Love thoroughly surpassed my expectations. Not only is this a new RHCP album, which is always exciting, but this one is imbued with extra quality, polish, and creativity. As Flea described it, "this is the best of us". Read on for a full review of the album.
Use Color Contrast To Enhance a Scene
When you think of contrast, you are probably thinking of luminosity contrast, but color contrast can play an important role in creating a vibrant, dynamic image too.
Directing Attention in a Scene
Darktable's powerful parametric masks, combined with the ability to layer multiple instances of a module with a separate set of adjustments applied to each, makes it possible to quickly make high-impact edits. In this example, an additional exposure module directs the viewer's attention to the picnic table, the focal point of the image.
And So It Begins... Again
JMS made a very surprising and exciting announcement yesterday (see the entire thread for additional details):
The original Babylon 5 was groundbreaking in many ways - the serialized 5-year story arc, the special effects, and the complex web of events and genres woven together. Moreover, JMS developed rich, 3-dimensional characters, many …
Q Returns
In a stunning announcement yesterday, we learn that Q will be making a return in season 2 of Star Trek: Picard! This is certainly some good fortune! With this announcement, and the clear theme of time in the above trailer, I'd like to reflect on some possibilities …
Why I'm a Fan of Mark Knopfler's Music
There are many things I like about Mark Knopfler's work, both his solo albums as well as Dire Straits:
Personal Geography
The way he weaves memories from his own life (even seemingly mundane things) brings a personal connection to his music. For example, taking the train in Southbound Again, remembering …
The Darktable Scene-Referred Workflow
Quickly get started with the darktable scene-referred workflow using easy, step-by-step instructions. Learn the purpose of each step rather than just clicking buttons and moving sliders, so these actions become intuitive when developing your photos.
Star Trek: Picard
Uplifting Resources During The COVID-19 Pandemic
Updated: 8/20/20
Below are some uplifting resources during this time of uncertainty and stress with the COVID-19 pandemic:
- Richard Davidson, the founder of the Center For Healthy Minds, discusses COVID-19 And Our Common Humanity. You can also use the Healthy Minds App to help manage stress during this …
Down The Road Wherever
Mark Knopfler's latest solo album, Down The Road Wherever (YouTube), is perhaps his best work since Shangri-La. His other recent albums (even including Get Lucky, which I reviewed here), have felt too folky for my taste and lacked hints of Dire Straits rock. Down The Road Wherever reduces the folk …
A Powerful Workflow Using LAB and Parametric Masks
Learn how to use parametric masks and LAB to change the colors in a sunset scene and add drama
A Successful New Star Trek Series - Updated
Here's his full statement:
Introduction
Sir Patrick Stewart's recent announcement at the Star Trek: Las Vegas Convention that Jean-Luc Picard will be returning in a new series is stunningly wonderful news. As I wrote back in 2015, there are several important qualities that I believe will make the next chapter …
A Royal Conclusion
I've really enjoyed watching Royal Pains over the last eight years, but it took seeing the finale to be able to really articulate why I like it so much: all of the characters give, and through their giving they receive what they need. For example, Hank helped so many people …
Ansible - Templating Config Files
Ansible is a fantastic technology that allows you to deploy and manage servers easily and in a repeatable fashion. One thing that can be tricky is using templates to create complex configuration files. In this example, I'll demonstrate how to use nested variables to create a sample Sanoid config file.
A Successful New Star Trek Series
The Fantastic Star Trek Lit Universe
Introduction
Ever since Star Trek Enterprise went off the air, there has been a void, a lack of new Star Trek TV or movies available to fans. The NuTrek films (the 2009 Star Trek reboot and subsequent movies set in an alternate universe) do not count, because although they are …
Understanding NFS Caching
Understand the different layers of caching involved with NFS shares and the settings to use on the server and on the client.
The Great Init System Debate
A great debate has arisen about which init system should succeed the venerable System V init system in the popular Debian GNU/Linux distribution. See bug #727708 for details. The two main contenders, Systemd and Upstart, each provide a set of important features while each offering some limitations. Systemd is …
This Is What's Missing From JJ Abram's Star Trek
I'm thrilled that Star Trek has returned to the big screen and that JJ Abrams has helped increase its popularity amongst mainstream viewers. This is very important to the franchise in order to attract new fans and continue to grow and produce new Star Trek …
Watch Hulu, Amazon Prime, Netflix, and More on Linux
UPDATE: Since this article was originally written, Widevine has become widely available on Linux distributions and allows for access to many popular streaming sites on both Google Chrome and Mozilla Firefox. For more information about each browser, see below:
Star Trek Destiny
Warning: this article contains spoilers from Star Trek: Nemesis, Star Trek: Voyager, and some minor spoilers from Star Trek Destiny.
I recently finished this 3-part Star Trek series by David Mack, which converges stories from Star Trek The Next Generation, DS9, Voyager, and Enterprise. Macks' story blends these …
Run Audiogalaxy on a Linux Server
Recently I have been looking for a way to stream music from my Ubuntu server to my iOS devices. I've investigated several options, including Plex, StreamToMe, iSub, Ampache, Air Playit, and others. However none of these* provide two features I really want to have:
- queue tracks as you are listening …
2011 - The Year of The Linux Desktop
Every year, members of the Linux community debate this question - will this be the year of the Linux desktop? Each passing year results in the same answer to this question - not yet. I think that 2011 is going to mark the end of this trend and see the beginning of a rise in use of Linux on the desktop because of several new and exciting projects.
Doctor Who - The Big Bang
It was definitely a heartfelt ending. I was skeptical to say the least of Matt Smith being able to fill David Tennant's shoes as The Doctor, but he has really done a superb job, especially with the 2nd half of the season. He brings a totally new element to The …
MobaSSH provides an easy-to-use SSH server on Windows!
As you know, I'm a Linux fan and can't live without remote SSH access to my boxes. Recently, I was forced to put together a Windows server instead of a Linux one in order to run my MagicJack (unfortunately, Virtualbox's USB Audio drivers aren't very good). I wanted to have …
James Callis Moves to Eureka
I have to admit, I wasn't very excited about the return of Eureka this season. Don't get me wrong, I think it is a great scifi show and really some of the best content on TV. I just wasn't in a rush or overly excited to start in on this …
Way to Go, Steve
As you have probably heard by now, Steve Jobs recently responded to the escalating Adobe-Apple conflict with a detailed and open letter explaining his thoughts on flash. Since the letter was published, there have been numerous responses (1, 2, 3...) to his letter, many of which try and accuse Apple …
Q & Data Using an iPad
This is the absolute greatest thing I have seen in a long while - John
DeLancie and Brent Spiner using an iPad. Two of the coolest guys in the
universe!! [via Gizmodo]
The Computer Paradigm Shift
In case you didn't already know, the iPad will go on sale tomorrow. This event marks the beginning of the next great leap forward for computers. This shift takes computers from the "desktop" model of managing files, folders, and devices to a task-centric model which abstracts these things from the …
Time-Lapse Water Photography
A long-exposure HDR photo on a river using both a neutral density filter and circular polarizer.
The iPad - My Thoughts
Finally it is here. There has been a lot of negative reactions to Apple's new iPad. Remember the reaction to the first iPod or the iPhone? Many of the complaints are things that can (and hopefully will) be addressed with software updates. This is a major new product which means …
Sanctuary - Sleepers
Another excellent episode of Sanctuary. I am continually impressed by the rich mythology of this show. After the exploration of the Ancients and their history in the Stargate franchise, I really began to appreciate how well those shows weaved their mythology together. However, I have been even more impressed with …
Bluetooth Support for Toshiba Laptops on Ubuntu
It has taken a long while for me to figure out how to get the bluetooth adapter in my Toshiba a200/a205 laptop to work with linux. I am currently running Linux Mint 8, which is a derivative of Ubuntu 9.10 Karmic. These instructions and tools apply specifically to …
Sanctuary - Veritas
What a fantastic episode of scifi. This week on Sanctuary brought a suspenseful and fast paced thriller to this already great series.
WARNING: the following review contains spoilers for the season 2 episode Veritas. After the nice character development for Henry last week, this episode was a refreshing fast-paced mystery …
Get Lucky
Mark Knopfler's latest offering doesn't disappoint. Throughout both the Dire Straits years as well as his solo career, Mark has always shyed away from the pop sound in favor of rich imagery and sound. Get Lucky is no exception. Right from the title track, Mark's unique style of weaving a …
My Thoughts on Mono
If you follow any tech news sites, you've probably come across the Mono controversy. If not, let me give you a brief introduction. Microsoft built on top of the Java programming language syntax to create a new language called C#. C# fixed a bunch of the programs with Java (such …
Managing Wine Bottles
Learn how to easily manage multiple applications in separate WINE bottles.