The Stylus isn't an Inert Element


This morning an article came across my feed that crystallized to me how wrong-headed the tech blogosphere is about the stylus. In this Read-write-web article, the author argues that the iPad isn't a proper drawing surface. I am in complete agreement with this point. A touchable interface is the cornerstone of the Tablet experience. Unfortunately, the Tablet fails when it comes to the production of artistic works. The author argues that the fault is the lack of physical feedback of the touchscreen. Instead, the software uses other kinds of feedback such as sound, graphics, or vibration. 

Which doesn't make any sense.

Most artists, particularly those that create 2D work such as drawings or illustrations, start with physical media. It's cheap, versatile, and yes, it's physical feedback is simply unmatched. Many webcomic artists start with physical media, and scan in their drawings to publish their stories. While this works, it has a number of drawbacks in the digitial world. Scans can be blurry or messy. Cleanup can take a large amount of time, and scanners can be fussy, broken, or unavailable. 

Enter the Wacom graphics tablet. I bought my Graphire 2 while I was in college early in the millennium. The $99 USB device still works and is still in service today. What's interesting about this bare-bones device is what it lacks. It has no display. No vibration. It doesn't even have buttons! Yet, I and many other artists can produce and continue to produce wonder pieces of art thanks to it and it's descendants. You'd think that the iPad and other tablets would be the ultimate "artist's digital sketchbook". 

But tablets suck at artwork. They are flatly unacceptable. The problem isn't haptics, or display resolution, or any of that nonsense. It all comes down to one simple thing:


Tablet touchscreens lack precision due to the nature of the technology. If you've ever held up a touchscreen and reflected light off of it at just the right angle, you'll notice a grid of "dots" cover the screen. Each dot is a tiny capacitor that can register a scale of contact. Clever (and highly patentable) mathematics are used to "guess" where you actually tapped on the screen. The problem is that capacitive touchscreens aren't manufactured to have the resolution required by artists. They are simply too expensive for the average consumer. 

Compare this with the technology behind a Wacom tablet. This device uses not capacitors, but a magnetic field using wires (circuit tracings) and a coil inside the stylus. The nature of this technology allows much greater densities of tap registration. With a little clever circuity in the stylus, pressure sensitivity can be measured with a minimum of additional components. This formula has worked well for Wacom, and digital artists for years and years. While it takes effort to get used to the lack of physical feedback provided by traditional media, a skilled artist can overcome that problem within hours. The result is clean digital lines without any scanning artifacts. 

But it has one critical problem. You need a stylus. 

The inductive system Wacom uses does not work with fingers. You can touch a Wacom tablet (with the exception of the Bamboo line) all day and not get a single click. Capacitive touchscreens take advantage of the conductive nature of fingers, and use that as a means to register taps. This is also why sausages work with touchscreens. In a mobile device world, this can be an advantage as only conductive objects register as taps, and it's unlikely you'll be carrying pieces of metal or meat in your book bag or pocket. Styli that work with touchscreens actually have a piece of rubber or plastic with a conductive coating. That's why they work. You can actually create a touchscreen stylus yourself with an old pen and some conductive foam commonly used to transport integrated circuits. 

The stylus has gained a bad reputation since the iPhone became the darling of the tech blogger world. This reputation is entirely undeserved, as the fault isn't the stylus, but the screens used at the time. In addition to Capacitive and Inductive, there's an older touchscreen tech -- resistive. The Palm series of PDAs heavily relied on resistive touchscreens. The physical configuration is similar to capacitive touchscreens, but relies on a different electronic property. When Palm was king, resistive screens were readily available and inexpensive. With a simple pointing device and again, clever mathematics, a tap could be registered and narrowed to a small region.

The problem is that resistive screens registered any and all physical taps. Furthermore, they had to be built using flexible material that deflected on contact. Capacitive touchscreens do not need physical deflection. As the size of the screens were often small in this age of mobile devices, a stylus was required to register taps accurately. Fingers were simply too mooshy. When Apple came along with the right combination of existing technologies, the stylus became the whipping child of an earlier era of technology.

The stylus is not the enemy. Bad touchscreen tech is. 

As of late, the Internet seems to be reconsidering the stylus. Thinkgeek popularized the idea of a capacitive touchscreen stylus to avoid the greasiness inherent to a finger controlled interface. Wacom has recently began producing a "premium" capacitive stylus under it's Bamboo brand. Yet, there hasn't been one article that doesn't repeat the words of Steve Jobs: "If you see a stylus, you blew it." The author of the article expands on this point:

Apple's second mobile operating system nearly eliminated the friction between the software and the physical human interacting with it. It felt like touching and manipulating the actual pixels. A stylus would just be an inert barrier in between.

And that is completely wrong when it comes to artwork.

For centuries, if not millennia, artists have used sticks of charcoal, quills, brushes, pens, and pencils in order to produce drawings and illustrations. These devices are long, usually cylindrical, and are often controlled by pinching them between the pointer finger and the thumb. Sound familiar? The stylus inherits this form factor. In addition to sheer familiarity, this form factor has been sucessful for one reason:

The stylus is not an inert element. It is an active, mechanical element that acts as a movement reduction device.

Leonardo da Vinci did not use finger paints, he used a brush. The stylus, pen, brush, and so on translates the relatively large mechanical movements of the hand into smaller more precise movements necessary for the production of detailed artwork. This was, coincidentally, why the stylus was necessary on Palm and Windows Mobile devices. The screens were smaller as they were more expensive to produce. The stylus allowed more precise input on the smaller surface.

Today, this remains a problem even on the relatively larger size of the tablet computer. Using a finger to produce artwork is akin to using finger paints. It's messy, clumsy, and the results tend to be prized the most by the parents of diminutive artists. A stylus is required to make artwork more detailed as fingers are too large to do it accurately. The problem is that current capacitive styli replicate not pens, but fingers. The tips are large and squishy, making it seems like finger painting with a cleaner, straighter finger. Pen-precise styli could easily be created, but the touch resolution of the average touchscreen is not yet up to the task. There are too few capacitiors, and they are too far apart.

The problem is not the stylus, dear tech bloggers. The problem is the screen