UPDATED as of 20th June 2014 to reflect N-Trig software advancements.
UPDATED as of 23rd June 2014 to reflect new direct Digitizer comparison information.
Those of you who may visit this site regularly will know that I am a game developer, but what you might not know is that I also do a lot of sketching. (Maybe one day I will post the stuff online)
Since I am a geek, I do almost all of my sketching digitally, which means I am always looking out for new developments in digitizer technology. This brings me to this post in particular:
Following the announcement of the Surface Pro 3, many artists were shocked and disappointed by the news that the SP3 would be using N-Trig technology rather than Wacom technology like the SP2. This is a perfectly understandable reaction, considering how the two have compared historically. A year ago, this news would have marked a fatal deal breaker in the eyes of all artists (including myself).
However, as someone who has used both the newest Wacom technology and the newest N-Trig technology on various tablets, I can tell you that the gap between these two brands is not as large as many still think.
This is a direct comparison post, between the most recent N-Trig digitizers and the most recent Wacom digitizers. I will compare the two technologies based on their practical performance. Both in terms of software and hardware. However, I will not compare the two on details like price. Wacom digitizers are significantly more expensive, but since that this does not ultimately effect the drawing experience, it is not relevant in the context of this comparison. I also neglect device specific factors like extra buttons and other details like N-Trig AAAA battery requirement for the same reason, this is a pure digitizer comparison.
N-Trig devices have 256 Levels of pressure, while Wacom devices can range from 512 all the way up to 2048. As far as numbers go, its is clear to see that in this regard Wacom devices are superior. However, it is important for us to understand what it means to have more levels of pressure. Having more than 256 levels of pressure only makes a difference if you are working with brush that is above size 256. In other words:
When drawing with a Hard Brush, at a Brush size that is lower than 256, there is no difference in sensitivity between Wacom and N-Trig
This is an important concept for people to grasp, because most artists do not work with brush sizes above 256. Furthermore, the difference does not become easily perceptible for a little while after that.
Some professions will require large brushes. For example: someone who is working on a poster that is going to be blown up to billboard sizes (and aren't using vectors) will definitely need a tool with higher than 256 Levels of pressure.
[Begin Edit] Since this topic in particular is of great interest, I will expand further to ensure there is no confusion.
Imagine using a 100px brush with a device capable of 100 pressure levels, and pressing down with 40/100 levels of pressure, 40% pressure. Based on common software implementation, this will draw a 40px circle. Now imagine using that same brush on a device that has 100,000,000 pressure levels, you press down with 40,000,001/100,000,000 pressure levels, 40.000001% pressure. The circle drawn is still only 40px wide. In this instance, you only need 100 pressure levels to hit every possibility, any pressure levels in between are simply not used.
The pressure curve (mentioned after this edit), can be used to squash the useful range of pen. Lets use a contrived example, mapping all pressure to half of the available pressure levels. We are still in a position where a digitizer with 256 levels of pressure is no different up to brushes of size 128px, which is still larger than what is necessary for most work. Even in the extreme case where someone wastes half of their pressure range, 256 levels is enough.
There are also other factors involved other than just brush size, you can use pressure to vary things like Opacity, Values, Jitter, and a heap of other factors. The point of this pure brush-size example was to encourage this type of thinking across to board: many programs have whole-number opacity percentages, or HSB/RGB parameters that only have a range of 100, 256 or 360. In many of these cases, it still makes little (in the 360 case) or no difference at all to have a more sensitive piece of hardware.
Now, there are a few cases where the average artist may use a much larger brush, for example, its common to use a very large air-brush for much smaller areas to ensure neat coverage. So if your immediate thought is that you never ever use brushes larger than 256, you may want to think again.
Furthermore, there is another point which I have neglected to mention which ties into the physical limitations of humans. It is very difficult for a human to apply force in small quantities and, when dealing with pressure levels in the hundreds or thousands, the difference in force between each level ends up being incredibly minute. This means that precisely using all the pressure sensitivity of your device is not easy, and some might argue that its outside of physical human capabilities entirely.
In summary, digitizer companies use pressure levels in the same way that many tech companies use specs: they count on a lack of public understanding in order to justify expensive upgrades that are largely unnecessary. 256 vs 512 vs 1024 vs 2048 is, for the most part, just marketing.
While the levels of pressure do not make difference to most artists, there are some other factors that do. The most important two are: The Pressure Curve and IAF - Initial Activation Force.
In mathematical terms: the Pressure curve is a function which translates your physical pressure (pounds of force) into virtual pressure. A steep pressure curve will mean that small modifications in your physical force will have drastic effects on the line that appears on screen.
The default pressure curve on Wacom devices is often described as more natural than the N-Trig curve. Furthermore, Wacom devices allow modification of the pressure curve to suit individual needs while N-Trig has no easy method of modifying the default curve.
The other factor, IAF, is the amount of initial force required before marks begin to register. On Wacom devices this is very small, last I checked it was 1 gram of force. For N-Trig devices the IAF is noticeably larger, partially due to the default pressure curve. These two factors are what places Wacom above N-Trig in terms of pressure sensitivity.
When it comes to drawing, nothing can be more invaluable than having your marks appear where you'd expect them to appear. This is Stroke Accuracy. When drawing with a Wacom device, you draw with respect to the hovering cursor, whether or not this aligns perfectly with your physical pen. This is something that you get used to over a short time.
On the other hand, modern N-Trig devices are very accurate (if not perfectly accurate) in this regard. The marks simply appear beneath the pen. For some, this is an invaluable experience. For others, working with the cursor in mind is satisfactory. In any case this is an area where Wacom needs to catch up.
Using either brand of digitizer, you can guide your cursor by hovering the pen close to the tablets surface. In the case of Wacom digitizers, this is important for you to line up your strokes. Hence, Wacom digitizers have a larger hover distance than N-Trig devices.
N-Trig devices also suffer from cursor lag when hovering. While your marks may always appear where the pen contacts the screen, the cursor may trail behind when it comes to hovering. Many artists who are not accustomed to this find it disorienting. For these reasons, the Wacom hover experience is superior.
The stroke delay is the time is takes from the moment you finish physically applying the pen to the screen to the moment the mark finishes being drawn. In this instance, your mileage will vary significantly based on the device you are using. Since this largely depends on the underlying hardware, it is not easy to say which digitizer is superior.
Just for perspective: My development machine at the time of writing is a Sandybridge 4GHz Hex-Core with 16GB of RAM and a HD6990. I have used a Wacom Cintiq 13HD on this machine, and still saw stroke delay when working with various brush sizes. On the other hand, I have a Galaxy Note 12.2, which is built with Wacom technology and I have not seen very much Stroke Delay at all. On the N-Trig side of things, I only have experience with modern N-Trig Laptops such as the Vaio Duo 13, working in Clip Studio Paint I did not notice any Stoke Delay when working with brushes at reasonable sizes.
The following is no longer true, see below for more information:
[UPDATE - 23rd June 2014]
With the release of the N-Trig Surface Pro 3, a direct comparison between it and the Wacom Surface Pro 2 can be performed. AnandTech, a tech review site has compared the pens in terms of latency, yielding a ~30ms improvement on the side of the Surface Pro 3.
|Surface Pro 3 vs Surface Pro 2 pen latency - Table taken from AnandTech|
Parallax is the perceived misalignment of the pen tip and the drawn mark as a result of the physical distance between the pen tip and the pixels of the screen.
If you have a tablet and you don't know what I mean: take it out, open up a fresh drawing and press the pen to the middle of the screen and move your head. If you are using most Wacom devices, the mark will no longer be aligned with pen in the way you thought it was. This means that, if you move your head while drawing, pen marks will start being placed in locations that you do not expect.
Some Wacom devices, such as the Note 12.2, do not have parallax issues as pronounced as, for example, the Cintiq line. But all Wacom devices suffer from parallax to some degree. On the other hand, N-Trig devices do not have this issue because their digitizer technology is very thin. For this reason, N-Trig is the clear winner here.
Drift & Calibration
It is well known that Wacom devices suffer from drift. Causing cursor alignment issues at the edges and corners of the screen. Since most software is designed so that toolbars and buttons are at the edges and corners, this can be a very irritating issue.
Wacom devices will require regular re-calibration to improve accuracy. However, this cannot fix the edge and corner drift issues, since they are a hardware limitation.
On the other hand, N-Trig devices do not require re-calibration and are equally accurate at all locations on screen. For this reason, N-Trig wins this catagory.
Software is a big deal for everyone using these devices, after all, it doesn't matter if one seems better than the other if they don't work with your favorite programs. In this regard, N-Trig has made significant strides towards ensuring compatibility across key programs.
The following is no longer true, see below for more information:
[UPDATE - 20th June 2014]
With the launch of new WinTab drivers coinciding with the release of the Surface Pro 3, all modern N-Trig digitizers can boast compatibility with Wintab software across the board. This includes, ZBrush, Corel Painter, Krita, Paint Tool Sai etc. In addition, more and more art software is being built using the generic tablet pc ink api, meaning that not only can you can use almost all legacy software, and will likely be able to use all future software with an N-Trig solution.
Furthermore, Wacom has a history of driver issues. These are, at best, minor annoyances and, at worst, can cause their products to become unusable for short periods of time due to loss of pressure or total unresponsiveness. In most cases, its not a deal-breaker for these issues to occur and the more severe problems occur very infrequently. However, driver bugs are just something people have grown to accept about the Wacom experience. Things like bugs and isolated issues should not have weight in this comparison, but these are not uncommon occurrences. Almost all Wacom tablet users will complain about driver issues at one point or another.
At this point, it seems inevitable to say that N-Trig wins this category, but there is one final factor that we have yet to discuss. Software built with wintab is optimized for wintab. This means that you are likely to experience (very slightly) reduced performance in software that added support for other devices later. While this is not as irritating as Wacom driver issues, it is still a consideration because it is a constant. I.e. While you may be able to find a fix for your driver issues, the same can't be said for the optimization of software. Digitizer users are at the mercy of software developers in this regard, and will be for a while.
Pressure - Wacom
Accuracy - N-Trig
Hover - Wacom
Parallax - N-Trig
Drift & Calibration - N-Trig
As you can see, the distinction between the two is not so clear cut. Ultimately, your decision will depend largely on your preferences. If it is invaluable to you that your marks simply appear below your pen, then you may want to consider an N-Trig solution. If you are a dealing with mega resolutions you will want a Wacom device. If you are irritated by Calibration or tend to switch tools often, N-Trig.
It is clear to me that the N-Trig vs Wacom debate is often driven more by historical prejudice than unbiased comparison. In my opinion, it is important for people to select tools based on merit rather than bias. Personally I am going to wait an see how the Surface Pro 3s digitizer holds up before deciding that it's the end of the universe.
P.S. For balances sake. here is a list of digitizer devices that I have owned over the years:
HTC Flyer - N-Trig
Lenovo Thinkpad Tablet - N-Trig
Cintiq Companion - Wacom
Sony Vaio Duo 13 - N-Trig
Galaxy Note 12.2 - Wacom