4 most important tech specs when shopping for VR
1. Field of View
Having a high field of view opens up virtual environments and makes us feel like we’re truly in another world. Human eyes have a horizontal field of view up to 270° (taking into account eye movement), granting us excellent peripheral vision and a generally good sense of our visual surroundings in the natural world. Emulating that as much as possible is crucial for an immersive VR experience.
If a headset’s field of view is too small, you might feel like you’re wearing ski goggles or binoculars, and be forced to move your head frequently just to discern your virtual surroundings. On the flipside, though, a high field of view would put a great deal of strain on your GPU to render graphics at the very edge of the frame, outside of your typical focus.
A horizontal field of view of 120° is currently seen as the best balance. But what about vertical? One big difference between Oculus’ Crescent Bay and Valve/HTC’s Vive, for example, is that the Vive has noticeably better vertical FOV, due to using two separate custom screens each oriented vertically. This has more impact on your experience than you might initially expect, allowing your eyes to dart up and down more naturally without encountering the dark edges of your headset.
When enthusiasts talk about VR experiences, the single word used to describe the holy grail is “Presence”: the feeling of truly being in a different place. A high field of view is undeniably crucial in achieving this, making for an important factor in deciding which HMD to pick up next year.
2. Pixel Density
With your eyes so close to the LCD screen, and focused through a pair of lenses, it’s no shock that individual pixels can become distinguishable. The dreaded “screen door effect” became the primary issue with the Oculus DK1 and DK2 due to each eye being exposed to a rather low resolution screen. Not only does the effect diminish the immersive experience, but it presents a practical problem when trying to read text that isn’t blown up to the size of a billboard.
The good news is that the first consumer headsets have improved considerably in this regard. Text is now readable, and distant objects discernable, with the screen door effect only being noticeable if you really look for it. If you plan to play games that benefit from being able to see greatly into the distance, or perhaps watch HD films in a virtual cinema, pixel density should be of particular consideration. Just remember that you’ll need a suitably powerful GPU to support these higher resolution screens, especially once we start seeing 4K panels in VR headsets.
One important thing to note is whether the headset uses separate screens for each eye. Using a single screen split in half ends up in a lot of wasted screen space, resulting in the resolution being effectively less than specified. Using a custom screen for each eye comes with many other benefits, such as a potentially better field of view, and better support of dual-GPU rendering.
3. Positional Tracking and Latency
VR headsets have evolved beyond just tracking your head as you look around. 3D positional tracking has enabled VR experiences to not only allow the user to lean around corners or peek over walls, but to get out of their chair and walk around virtual environments. However, not everyone will want to convert their basement into a dedicated holodeck! So if you’re just planning on exploring virtual worlds from the comfort of your couch or desk chair, the basic positional tracker that will be bundled with most headsets will suffice.
As always, a large factor at play in the quality of head tracking is the machine (i.e. GPU) rendering the virtual world. Dropped frames can result in choppy tracking, which can not only ruin the experience but also feel quite uncomfortable, as your brain struggles to process why the world around you has become a slideshow. Similarly, latency between the tracking and the display can lead to an unpleasant drunken feeling as your vision lags behind your head movements.
In general, the upcoming consumer VR headsets all have excellent latency and tracking – it’s up to the user to ensure their graphics hardware is capable of running whatever VR experience they’re viewing. Lowered graphics settings may be required for some games in order to maintain smooth tracking for all but the most top end GPU owners.
Not all upcoming headsets are expected to ship with controllers, but many will; and it’s likely that using the right controller for the right VR experience will act is a ‘Presence-multiplier’. That is, the sensation of Presence granted by a quality headset can be amplified by the controller used to interact with the environment.
While being able to shoot laserbeams by aiming your head sounds like a great time, the general reaction to such a control mechanism has been generally negative. Seen as being uncomfortable and fiddly, a number of VR-dedicated controllers in development is increasing, from nunchucks and other weaponry to full-body sensors that let you truly control every limb of your avatar in 3D space. Even pre-existing controllers, such as flight sticks and steering wheels, are capable of greatly enhancing your VR experience where relevant.
If you’re mostly interested in watching VR movies and enjoying otherwise more passive experiences, certain controllers – such as the SteamVR controller – may still prove helpful for navigating between experiences without having to worry about regularly taking off your headset. Sensing where your hands are on the controller makes navigating menus a lot easier than stumbling around trying to find your keyboard blindfolded!