Essentially, the larger the screen an installation can take the better. As the screen increases in size, the sense of immersion increases and the effectiveness improves. Virtalis is exceptionally well placed, to give advice on configuration and system layout for any specific room.
A wide range of materials for the screen surface are offered, both solid and flexible, and each is custom made to the size required. The most cost effective are those made from a flexible material. These are securely mounted in a high quality non-ferrous frame and mounted on a wall for front projection, just like hanging a picture. For the rear-pro option, the screen is installed within an aperture in the projection room wall; the void in front of the screen is for the audience, while the void behind the screen is for the projector and hardware.
Solid screens are manufactured from either a sheet of cast acrylic or glass. These are far more expensive than soft screens for a number of reasons. Firstly the material is more expensive, but they are also heavier and have to be shipped flat (as obviously they don’t rollup or fold), shipping costs are therefore much larger (which can be as much as the cost of screen itself!) and the installation too takes longer and requires more people. Typically solid screens are suspended in the frame to prevent them from bowing under their own weight, whilst gravity helps to maintain a perfectly flat projection surface. They are also generally clamped along their lower edges to maintain their flat shape.
Virtalis always chooses “best in class” and “fit for purpose” components for its VR installations. We are independent, but we maintain close relationships and even partnerships with key suppliers. In the realm of screens, those two companies are Stewart Filmscreens and DaLite.
A family-owned business since 1947, Stewart maintains the highest standards in screen design, craftsmanship, and customer service. Stewart Filmscreen staff are expert product specialists ready to accommodate your most complex screen designs. As a result, Stewart specialises in making custom screens designed to fit your specifications, meaning you are never restricted or limited to "off-the-shelf" styles or sizes.
Da-Lite has been in the film business for over 100 years. The Company offers a dizzying range of front and rear projected screens and claims to design, manufacture and market the most comprehensive line of projection screens in the world. Currently, Da-Lite offers the widest selection ever of proprietary projection screen fabrics and materials in its history
There is an enormous range of projectors for both the 2D and 3D markets. Virtalis supplies both, but our expertise lies in stereoscopic, 3D systems and here we really can guide you through the maze. 3D projectors draw on differing imagery technologies: LCD (liquid crystal display), DLP (Digital Light Processing), LED (Light Emitting Diode), LCOS (Liquid Crystal On Silicon) and D-ILA (Direct-Drive Image Light Amplification) which is a proprietary LCOS technology. Virtalis uses DLP in most of our active VR systems, such as ActiveCube or ActiveWall.
Resolution is key to the suspension of belief in 3D and is a result of the combination of the number of pixels projected and the size of the screen. In order to be believable, we always recommend that the system represents the product at as close to 1:1 scale as is possible. With some of our customers designing large agricultural machines or even larger products, our screens can be very large (7-8m wide and more). ActiveWorks systems become more ‘immersive’ as the viewer’s peripheral vision is filled. And the more you are immersed in the environment, the easier it is to believe in the 3D qualities of that environment, increasing the effectiveness of the system.
In most installations, in particular, those in engineering, we are being asked to render ever more complex models, for example: complete wind turbines, ships and even power plant. These models contain a lot of small details such as nuts, bolts, rivets, facets, cables etc. So the quality and detail apparent in these images is critical to the user. Screens have to be small enough to fit in the room, but more importantly the image needs to be close enough to scale to be believable and large enough for details such as nuts and bolts to be selectable. For this reason, we always propose the largest possible screen. Screens do not have a huge impact on the cost of a system unless they are solid screens.
Projectors come with a range of resolutions and aspect ratios denoted by a dedicated nomenclature.
XGA 1024 x 768 (4:3)
WXGA 1280 x 720 (16:9)
SX+ 1400 x 1050 (4:3)
HD 1920 x 1080 (16:9)
WU 1920 x 1200 (16:10)
Single Chip DLP
Ultra portable, single chip DLP projectors of the kind deployed in our ActiveMoves, have a maximum resolution of 1280 x 720 and brightness of around 3,000 lumens, but are rapidly becoming brighter with higher resolutions.
Larger single chip DLP projectors tend to have a maximum resolution of 1280 x 720 and are capable of producing a maximum of 5,000 lumens. These projectors have additional options, such as interchangeable lenses, lens shift and more inputs. However, the colour wheel typically does not provide the depth and accuracy of that found in projectors that use three separate chips. Use of a colour wheel can also result in the “rainbow effect”, so that the viewer will sometimes see “rainbows” when bright objects are displayed on a dark background or when the viewer’s eyes pan across an image.
3-chip DLP projectors are also widely used within ActiveWorks. Brightness ranges from around 3,000 lumens to over 30,000 lumens per projector, with resolutions from 1,400 x 1,050px up to 4,096 x 2,400px. These professional, installation grade projectors also come with a huge range of lenses and other accessories. Virtalis has used 3-chip DLP projectors in over 200 installations over the past five years. Virtalis believes 3-chip DLP technology offers extremely high contrast ratios, better colour separation and darker black levels.
Xenon lamps produce highly stable images and the whitest of whites without the need for artificial white boost, as is typically the case in single chip DLP projectors. The latest projectors now have the option of Mercury-based lamps offering similar quality images using a more power efficient lamp. This allows the projector to run cooler, using less power, and more quietly than the Xenon-based units.
In keeping with our stance as arbiters of the “best kit for the application”, we maintain close working relationships with the top projector manufacturers – Christie, Optoma and Digital Projection.
Our Technical Director, Andy Connell, was recently invited by Christie to give his input to the next generation of their high end projectors. The Christie Mirage projectors are probably the current industry leaders and offer the broadest range of 3-chip DLP 3D active stereo projection up to 120Hz in either a single projector, or a multi-projector array. These projectors are designed specifically for 3D applications for all types of immersive environments including ActiveCube and ActiveWall.
More affordable are Optoma’s projectors. We have been impressed by their professional range. High brightness output, excellent connectivity and greater versatility are their hallmarks. Optoma projectors incorporate the latest DLP technology from Texas Instruments, together with advanced optical engineering expertise and dedication to superb product quality.
Digital Projection are a digital imaging pioneer in the manufacture and distribution of an extensive and expanding line of ultra high-performance 3-chip and single-chip DLP projection systems.
There are, of course, a wide variety of workstation options available, but they are generally categorised in to three areas; portable, desktop or cluster.
Virtalis has gained a high level of experience with a wide variety of workstations over the years, including Sun, Dell, HP, SGI etc. We look for a number of points when specifying a workstation for demanding visualisation tasks, such as speed, capacity, flexibility, robustness, efficiency, worldwide technical support, ease of service and maintenance.
Often, we recommend Dell Precision workstation owing to the great value afforded by the build quality, international customer support and flexibility.
Our PCs come pre-fitted with a high-end NVIDIA graphics card, which deliver the performance necessary to drive most models. These graphics cards are heavily tested and well proven for VR use and provide world-leading performance. The card and PC always comes configured for stereo output (although mono is also supported).
Note: The latest NVIDIA driver comes with a dedicated 3D VR Virtalis applications mode for optimised performance.
A Virtalis CLUSTER solution consists of one master node and a number of slave nodes. These rack mounted workstations come configured with high clock speeds, large HDs, memory and high-end graphics. They are also configured for stereo output (although mono is also supported). Additionally our clusters have VNC support.