For the church and Christian presentation vision is any visible digital or analogue media used in presentations or at events. Equipment in the vision department ranges from projectors and TV's to computer monitors (display devices) and media players like DVD, VHS and computers (media playing devices).
Typically computers with a DVD/Blu-ray drives have replaced specific media players like DVD, CD and Blu-ray players as computers are able to handle all 3 disc based formats; reducing the amount of devices needed to do a show.
Vision Technology is normally used to display extra content while a performance or event is going on however there are events such as movie screenings or similar events where what is being viewed by the audience on screen is the main event.
Examples of events where Vision is a supporting tool:
• Musicals - virtual sets and time/date/town displayed
• School assemblies – presentation is giving extra information on what the presenter is talking about or providing a visual aid
• Church service – song words are projected on a screen; eliminating the need for hymnbooks
Examples of events where Vision is part of the main event:
• Movie screenings
• Video games events or competitions: where the game in the competition is being projected for the audience to see or live streamed.
Before I start let's look at the work flow a general event might have; that has 2 computers running.
The first computer in our imaginary set up is the main presentation computer. Its job is to drive media for every show. Now the work flow on this computer is different from your normal home style PC and the first thing you will notice is that there are two screens. The reason for the two screens is that the operator has a screen for showing what the projector is displaying (mirroring what the projector is showing) and the other is for preparing media to be displayed.
It's also common for a venue to have a second computer or a wall/floor port so a presenter can bring their own computer and run a presentation from where they are presenting. About 99.9% of the time they will only need one screen, unlike the main display computer because the presentation the speaker will be preforming will be a lot less demanding and not require a second screen.
Now let's go into some general equipment. A general set up will have a projector a switch box and a splitter box, monitors and a lot of video transfer leads like VGA, DVI or HDMI. Just to let you know the cable format that will be in the illustrations will all be VGA but in the real world you can use any cable format you like.
Switch box
A switch box allows you to switch the input being sent to your projector. In general a switch box will take several inputs and allow you to switch between them. Each input on the box will normally have the same connector type.
This means when you get a switch box make sure to get one that has the same connectors on the range of devices you will be using. I'd recommend VGA a switch box because every PC normally has a VGA port or a HDMI switch box as this format is becoming more popular and also supports larger resolutions and 3D. Most likely you will only need a switch box that can take 2 or 3 inputs as most events will not require more than 2 devices running to the projector through the switch box.
Figure: A VGA 3 way switch box
Things to note about switch boxes:
• If you can't get a switch box don't worry most projectors can take multiple inputs but for a permanent set up a switch box is a lot nicer to use and will give a nicer flowing presentation.
• Some more expensive switch boxes also double up as a splitter box so a separate splitter box may not be necessary.
Splitter box:
A splitter box is what allows a secondary monitor to show the same image that the projector is displaying. It takes the display output from your presentation computer and splits the signal into two outputs (one goes to the projector and the other goes to the secondary monitor). You could also get a splitter cable that does the same thing for a much lower cost although your maximum cable length you can use will not be as long.
Figure: Splitter box and Switch box configuration with rest of equipment
Cable
Cabling is normally very expensive, for instance a 10m VGA cable is about $100(AUD) and adding extra meters past 10m causes cables cost to go up exponentially. Furthermore, cables such as HDMI are limited to 12m before the signal stops. VGA has can go for longer but after 100m-150m even with good quality cable the signal stops.
The solution to this is to run CAT 5 or CAT 6 cable which is cheap and reliable. Unfortunately, it does require converters for your computers native output to CAT 5 or CAT 6 and then another one to convert CAT 5 or CAT 6 to the projectors native input. Alternatively you could get boosters to amplify the signal for the distance but that does mean you need a power sources along the rout the display cable is travelling to power the boosters.
Screens
Screens are not a great part of my knowledge base. I can't recommend which ones or brand to get but I would recommend something that can handle the same resolution as your main display device.
Another factor that limits my knowledge base is I run a laptop as a main presentation computer and I have a custom built screen that matches the resolution of the laptop's screen and the projector runs at the same resolution. The screen is recycled out of on older Toshiba laptop that the Mother Board died on and I bought a LCD screen driver off eBay.
Building a screen like this can be cheaper but I'd recommend you get store bought screens as it will be a lot less hassle in the long run.
Projectors
Projectors are another area I don't like to discuss. I know more about operating them than providing advice on buying one. But I can say this:
• BUY THE MOST EXPENSIVE ONE YOU CAN GET. Why? A more expensive projector will last longer and have better functionality, have more input and output variations as well as more lumens (light per m2) which will allow your projector to run in brighter places. Anything under $1000 dollars is not going to be powerful enough for a large room and I'd really recommend something more expensive (~$2000+).
• Replacement bulbs will also be easier to find on well-known brands and before buying a projector make sure you will be able to buy bulbs and the store is supporting replacement parts for the projector because over a 10 year or so lifespan it's likely the bulb in the projector will need replacing.
Presentation Computers
I'm just going to go with, get a PC.
Why you might ask? Well there are several reasons:
• The majority of people that will be operating the main presentation computer will have experience using a windows based machine. Putting someone on a Mac that has little understanding on how the operating system works adds extra stress to the already stressful job of running a presentation.
• No display port adapters are required.
• A larger choice in hardware and drivers, therefore you have the ability to tailor the hardware of a PC for your specific needs.
• Cost - A PC is going to cost less than a Mac
• The windows operating system is a lot nicer to work with when running shows.
• Office and particularly PowerPoint is a lot more user friendly on a PC and runs a lot smoother than the Mac counterpart.
A lot of my PC bias for a presentation computer comes from experience using both operating systems in events. I'm proficient in using both operating systems but I do feel that a PC would be the better choice out of the two platforms.
Zach Radloff lives on the Gold Coast and is studying IT technology at university.
Zach Radloff's previous articles may be viewed at www.pressserviceinternational.org/zach-radloff.html