Tag: projector blending


Meet the Team – Paul Blackham

paul blackham gbvi projector edge blending.jpegIn this blog we talk to Paul Blackham, Developer at GBvi – he’s not always in a client-facing role, but all of our customers and projects certainly see and benefit from his expert programming skill.

So, tell us a little about what you do at GBvi

A major part of what I do is to develop the design tools we use during the early stages of each project process – the ones that help map system design and accurately produce layout data for our customer projects. Occasionally I work on system blending designs too and am increasingly working with the team to gather data for various projector models that we can use in blend analysis.

Typically, what’s your involvement in projects?

My involvement in projects usually depends on the scope of the client requirements. On some projects, we play a key part in the design optimisation process of the display system, helping the client to build and specify the optimum configuration. On others, we are contracted to design and supply an optimised blending system where the client has already signed off on projector layout.

What’s your background?

I have a degree in Games Art and Design, so not really from the sim or viz industry as I know it now, but I still find there’s a huge amount of overlap and similarity in the worlds of simulation and gaming. I’ve spent a lot of time with CAD software, 3D modelling and programming which has really been put to use here.

Tell us about the kind of projects you work, and what you’re most proud of

Unfortunately, we’re unable to mention the specifics of many projects we work on for obvious reasons. Recently though, I’ve been working on the delivery of a project for a search and rescue helicopter training programme. As a display system, it’s actually pretty complex with 11-channels of projection. I’ve recently developed new design tools that have overseen the entire project for us from initial design process through to completion – the creation of the masks was then handled by our usual in-house team.

What keeps you on your toes at GBvi?

We’re always testing the compatibility of projectors which can be a little challenging. If we receive a new enquiry that specifies a model of projector that we haven’t tested before, it’s not simply about pricing something up. It can mean the start of an R&D project where we often have to simulate the client environment by bringing in new screen shapes or material. We need to ensure our performance specification is accurate first time around and have to go the extra mile to achieve this.

What do you enjoy most about working here?

I find it really enjoyable to get into the programming side of things, particularly seeing how the tools I develop consistently produce high standard results and streamline the process. Plus, we have a great office in the Sussex countryside, yet I’m still able to live right on the beach in the bustling city that is Brighton.


GBvi to speak at ITEC 2016

ITEC 2016 is the annual forum where representatives from across the military, industry and academia connect and share knowledge about military simulation, training and education community. For more information on ITEC 2016, click here.

Geoff’s ITEC 2016 presentation is titled ‘Optical Blending – Difficult yet Essential for Maximising Dynamic Range of Projection Displays’


Here’s a snippet of the abstract…. For full details or to request a copy of the presentation, please contact us


Quality projection displays for visual simulation have evolved to use mainstream commercial projection devices, which, together with automatic alignment solutions, have dramatically reduced time required for their installation, alignment and maintenance. However, one bugbear has remained in the form of projector light leakage when displaying dark scene content.

Electronic blending solutions exist that produce excellent results for bright scenes but, for continuous background intensity levels in dark scenes, one must use infill techniques that sacrifice precious dynamic range. Often, solutions are commissioned that sacrifice up to 75% of the possible dynamic range, on the basis that ‘it’s the best you can get’. Often, this trade-off is not even apparent to the end-user, who therefore understandably assumes that the resulting performance really does represent the state of the art, which in turn limits the useful application scope of an expensive simulation system. Optical solutions to blending multiple channels can solve this problem, offering the promise to increase the utility and hence value of visual simulation training substantially, yet often this option is not even considered – so why is this?


Factors limiting the take-up of optical blending include: –


  1. Difficulty: implementing optical blending has proven to be surprisingly difficult. While standalone projected image quality of commercially available projectors is often excellent, optical characteristics tend to be unsympathetic to simple solutions. A systematic and well-founded methodology can lower this barrier substantially.
  2. Higher contrast projectors are available: even displays employing some of the more recent high-contrast projectors would benefit from optical blending – almost to the same degree as lesser contrast examples, owing to the enormous perception range of the human observer over a wide range of viewing conditions.
  3. Cost: while cost of the display system is certainly increased by the addition of optical blending hardware, it is a low proportion of visual system cost and the performance enhancement can represent value well in excess of this increase. Optical blending implementations – which place physical masks in the projection light paths – have been around for a long time, but a universal solution for all projector types and scene content has yet to become available. Many solutions give relatively poor performance that can be tolerated for dark scenes such as those experienced in night training, so are actuated out of the light paths for use with daytime scenes. These present logistical challenges to simulator users, where a choice must be made as to what ‘mode’ you are training, or some transition must be suffered while the blending system switches mode. Other solutions cannot withstand sustained light flux without degradation, so again must be actuated, while yet others may cause image sharpness degradation in the blend regions, so must be designed very carefully to limit this impact, particularly with high-resolution projectors.

The purpose of this paper is to inform the simulator operator and trainee community of this key area of visual system optimisation, including its cost-benefit analysis. Included in this will be a review of the mainstream projection technologies and their respective pros & cons, particularly with regard to scene dynamic range and blend implications. This in turn leads to a detailed review of optical blending options, presenting their operating theories and application scope. Finally, a new active optical blend technology is introduced that widens the range of display types that can benefit from high quality optical blending.


Geoff Blackham talks to rAVe about optical blending & Void

Want to know more about our Chronos Optical Blending Solution, and ‘Void’ – our brand new infinity display experience for attractions and leisure simulation?

Watch the rAVe pubs video interview with our Founder & MD, Geoff Blackham, at ISE 2016 in Amsterdam.