3. Setup

Thu - July 6, 2006

mixing onstage vs mixing in a control booth

Which is better - mixing onstage where the action is, or mixing in a control booth?
Read on to see how the two compare...

Most of the time, when doing VLOBLIVE gigs, I end up onstage somewhere with my PPU - often tucked in behind the speaker stack at one side. It's not ideal, but it works.

Recently I did a gig where, for good reasons to do with using installed gear, I ended up mixing in a control booth with a window into the auditorium.

Wow! What a difference. The main difference was the sound level - much quieter, much calmer.
No shouting required just to be heard by the camops. The effect on the show was to calm things down and make it less stressfull for all concerned.

So was it better? Well...yes and no. It was quieter and less stressful, but it was also more detached and remote and I didn't really feel like I was part of the event. It was harder to get 'in the zone' and stay focused on doing a great mix, not just coasting along with the obvious shots.

So there's pros and cons for both, and often the circumstances of the setup will dictate one or the other.
If there are no control booths, then there's no option, unless you can comandeer a room behind stage or something. Also in this case there were video tielines built into the control booth, so running cables was very very easy.

On balance, if it's an option I think I would pick the control booth any time - just makes it all much more manageable, BUT only if I could get a good view of the stage to see what's going on.

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Fri - March 3, 2006

Easy way to work out how close your FOH cameras have to be..measure it!

One of the eternal questions for VLOBLIVE video is how close do the FOH cameras need to be to get good shots. The answer, of course, is ...it depends..read more for details.

Camera positioning can make or break your IMAG at a VLOBLIVE gig, and one of the key issues is how to get good closeup shots from front of house (FOH), i.e. out in the audience. You want a camera out front because that is where the talent will be looking, and to engage with the audience they have to look INTO the camera.

So... how far away can you cope with?

Well, it depends on a number of factors and it can be quite hard to compare because:

Just knowing the focal length doesn't tell you.
A 105mm focal length may seem like a lot but it is different on a 1/5 inch CCD on a DV cam from a 2/3 inch CCD on a pro studio cam.

Just knowing the zoom range alone doesn't tell you.
You can have a big zoom range e.g. 20x, but of course if it starts at extra super wide, it won't get that far towards telephoto at the other end.
Also, many consumer DV cams boast fantastic zoom ranges, but they are including the horrible 'DIGITAL' zoom in that, which throws away pixel info and should NEVER be used in an IMAG setting.

You CAN work it all out mathematically, but, to be honest, life is too short to explain that one in detail, so I suggest a more empirical approach.

Sometime, when you are not so busy (like NOT at a gig??) set up your camera in a large enough space, e.g. outside, and try it.

All you need is a measuring tape, the camera, and a willing volunteer.

Get your willing volunteer to gradually move away from the camera while you frame up a nice tight head and shoulders shot on them. I mean tight here - the top of their head should be at the top of frame, and the edges of their shoulders should be just about to go out of shot. This is the least-close-closeup you can really get away with on an IMAG gig. If you can't get this shot from FOH you are going to struggle to convey the emotional intensity of the gig.

Of course you will have to keep zooming in as your volunteer moves away, and eventually you will run out of zoom range. Tell the person to stay there, and then measure the distance from the camera to them. That's it. That's your furthest-away-this-camera-can-ever-be distance.
Yes, of course you CAN go further away, if you absolutely have to, but you will miss out on this key shot, unless you can get it some other way.

Once you build up a list of all these FATCCEB distances, you can plan where to put your cameras long before you get to the gig.

Finally, a word about tele-converters.
They suck, mostly.

You may be tempted to whack a 2x or 4x (or more!) teleconverter on the front of a DV cam and revel in the monster you have just created, but, unless you have paid serious money for the teleconverter the results will be...well... pants actually. Softened image, darkened corners, failure to autofocus, screwed up colours etc. - these are all symptoms of cheapo teleconverters

My advice is buy very very carefully, and stick to 1.5x for screw on types.

Pro lenses with built in 2x converters generally work OK, but you still lose some sharpness and some light. You may end up with two FATCCEB distances for these cameras. One with the 2x in and one with it out.

OK - that's it. Just do it.

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Thu - March 2, 2006

Use a cheapo LCD TV to give a better idea what your LCD projectors are showing.

One way to better ensure that what you see is what the audience get is to use an LCD TV as your program monitor. ... read more.

It's fairly common practice in Video mixing setups to have a 'program' and 'Preview' monitors. The Preview monitor lets you cue up what's coming next and the Program monitor mirrors whatever is going to the main LCD screen. The latter lets you set up out of the way, and still see what the audence are seeing....or does it??

Usually these monitors are small (10"-14") CRT video monitors. The problem is that it's often hard to match the image brightness and colour saturation between a CRT program monitor and an LCD projector with lower contrast ratio and different colours. Shots that look great on the CRT look terrible on the LCD projector due to the lower contrast ratio and differences in colour. Of course with Pro projectors this isn't a problem, as they are capable of producing reasonable video, but for those of us pressing what are essentially business projectors made for Powerpoint into service at a VLOBLIVE gig, this is a real issue.

the first time I used a small cheapo LCD TV as my program monitor (because I had run out of other monitors) I was really surprised to notice that the match in contrast ratio, brightness, and colours was MUCH better than with my normal CRT video monitors.

Notice I say it was a better match NOT that it was good. The LCD TV had poor contrast ratio, poor brightness control and odd colours BUT they were overall more similar to the Projector and therefore I knew that if a shot wasn't working on the LCD TV it probably wasn't going to work on the projectors.

Small LCD TVs are getting really cheap now, so this is definitely worth trying out.

Oh, and as a bonus, they are MUCH more portable than their CRT counterparts.

P.S. You will still want to setup the contrast and brightness properly, as detailed elsewhere on this site.

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Sun - August 21, 2005

Debugging S-Video problems

There are some specific tips for debugging S-Video connections on two separate Co-ax cables (one for luminance (Y) and one for chrominance (C)). Here they are...

S-Video uses separate connections for the luminance and chrominance signals, but now instead of just debugging one connection path you have to debug two. Here are some pointers.

1. the video sync pulses, used to indicate the start and end of each line and field of video are added to the luminance (Y) signal, so if you are not getting stable images at all, it is likely that the Y connection is broken somewhere. Typically you might get a rolling image that is recognisable but is never stable.

2. If you ARE getting a stable image, but it is monochrome, then there is likely to be a problem with the C connection.

3. The most common problem with Y/C connections using dual Co-ax cables is swapping the cables somewhere - i.e. connecting the Y to the C and the C to the Y.

4. Some projectors double up the composite and the Y connections on the same BNC and then have another BNC for the C. In my experience you HAVE to enable Y/C operation, otherwise you will only ever get monochrome images.

So to summarise the symptoms match the problems as follows:

Y connection broken - no stable picture (rolling image) or no picture at all
C connection broken - stable picture but mono only
Y and C connection broken - no image at all
Y and C swapped - no stable picture or no picture at all

So, if in doubt you should always try to sort the Y first, to get a stable picture first, then sort the C to get colour.

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Making a PC usable on a tiny TV monitor

From time to time you may end up having to operate a PC connected to a scan converter WITHOUT a monitor, i.e. the PC is connected directly to the scan converter and the only place you can see the screen contents is on a Video monitor or projector output. This is fine when it is displayed on a big screen, but when all you have to go on is a tiny 4 inch preview monitor, it is much harder to control.
Here's a quick way to make it more visible, using the accesibility settings in Windows.

Running your PC graphics through a scan converter results in a loss of resolution and especially on a smaller monitor all those nice windows menus and text get pretty squished and fuzzy and it's hard to navigate around.

You could drop the screen resolution but that would screw up all your nice pp slides.
Here's a quick way to fix things so you can see what you are doing

in Windows 2000

START....SETTINGS....CONTROL PANEL...ACCESSIBILITY OPTIONS...DISPLAY (tab) then tick "use high contrast". and OK.

You will then get this...

Much easier to read and navigate on a tiny 5 inch preview monitor!!

NOTE - resolution of powerpoint slides etc is unaffected by this method

Also results are pretty patchy in some apps. Worth trying before you assume you can use it.

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Adjusting brightness and contrast...the proper way. (Updated)

Brightness and contrast are among the most misunderstood controls on most monitors and projectors. Here's a way to ensure that they are set up properly...

First, ignore the names. No, really, ignore what they are called - it REALLY doesn't help.

Instead of brightness think "black level" b = blacklevel.
Instead of contrast think "video gain" c = crushing the video (i.e. squeezing it down or up)

and you will be much closer to understanding what they do.

The brightness control adjusts the video level that the monitor treats as true back. The goal here is to match things that the sending equipment thinks is black to actual black on the monitor. There are various reasons why these might not be the same to start with.

The contrast control is like a gain control on the video. It adjusts the overall range of the incoming signal in terms of the histogram of brightness. The more 'contrast' the more gain is applied to the incoming signal and vice versa. Think of it as 'turning up the volume' on the video and you are not far off.

The key then, is to get the black level right so the left hand end of the histogram is in the right place, and then adjust the 'volume' so the right hand end is in the right place too.

The good news is that you don't really have to understand any of the above to get it right.
So...how do you do that?

The way to achieve this is to use a test chart.
I am amazed at how many people try to adjust projector setting by eye without using a decent test image to make it easier

Here's what you need

A grayscale test chart.

Here it is as a Powerpoint file, all set to load up on your PC and display on your projector.
grayscale test chart.ppt

and here it is as a PNG image

(Just save this image)

Stick this up and follow the instructions on-screen. It's that easy

You want the brightness to give you a good dark black, but still be able to just distinguish the next along black bar, and the contrast to give a good strong white, but still be able to distinguish the next along white bar. These two controls interact so be prepared to fiddle a bit.

Do this for ALL display equipment - monitors, projectors, plasmas etc. and you will be a lot closer to getting good dynamic range in your video signals.

NOTE: When you do this, you may end up saying " now my white isn't white enough to be seen". That is a problem with the brightness of your projector, not with the settings. You can compensate for lack of brightness by boosting contrast, but be aware that this will blow out all the light parts of the image, which may look fine for song words, but will look terrible for video.

P.S. I made this test chart myself in Photoshop, rather than ripping off an existing one.
feel free to use it, but don't distribute it and pretend it's yours, or sell it to anyone.

P.P.S. If you are using this test chart through a scan converter, remember that the black and white levels are going to be dependent on the scan converter settings too.

That touches on the subject of 'video gain' i.e. how the signal get's handled as it travels through the system - that will be the subject of another post.

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Problems with projector brightness

"This projector is just too bright" - not something you hear too often at VLOBLIVE gigs! So is there anything you can do, short of shelling out more cash, to improve the problem of projected live video being too dark.

Before we dive into discussions of brightness, remember that it's not necessarily about brightness, but actually more about contrast ratio between white and black. Sometimes a brighter projector can have a poorer contrast ratio and look worse!
For something like words or powerpoint, you can really boost the contrast on the projector to get it nice and bright, but when you do that, anything that is more subtle, like video, looses all the detail in the shadows and darker areas.
It's almost impossible to get a good balance when you only have one set of controls. You either end up with dull graphics and OK video, or bright graphics and invisible video!!

The good news is that there ARE things you can do to improve this situation, without necessarily spending LOTS more money on new projectors etc. Some are obvious, while others may not be.

Here are some suggestions:

1. Setting up the video projectors properly always helps. This doesn't mean ramming the contrast and brightness up to max, as some people believe.
I have an article on this subject on my live video website here :

Notice, this may mean sacrificing some of the 'brilliant white' from graphics etc, in order to save the video.

2. You need to check whether you have your video 'gain structure' set up properly. This involves checking the signal levels along the path from source to projector to ensure that when you think you are sending 'white' to the projector, what it receives really is white, not light gray. Same for black levels - if you only give the projector dark gray instead of black, you can't blame it when the contrast ratio is squeezed!
Often scan converters or long cables etc, can affect this. Send me a system wiring diagram and I will tell you whether this is likely to be a problem. Best way to do this is with a waveform monitor, or with a DV cam and a laptop with a DV in firewire port. (There is free software you can use to give you a 'virtual' waveform monitor)

3. You need to confirm that your sources (especially the cameras) are giving the brightest signals possible. Again are they sending 'gray' rather than white? Is their black level set properly? What is their gamma set to? Can you boost the exposure on the camera? Or add more gain?

4. You need to do EVERYTHING possible to keep stray ambient light off your screen. This may mean adding window blinds, fitting barn doors on lights, moving light fixtures, turning some lights off etc etc.

5. The choice of screen material and colour matters a lot. I don't think you have any screens at all downstairs do you? Again, the lack of a black border, and the matt white wall may not be the best solution. Strangely a mid gray coloured screen material can actually give a better perceived contrast than a white one, especially for low contrast ratio projectors. And apparently putting a black border round the image (as most screens have) makes it look higher contrast.

6. It may help to add a 'Proc Amp' box or video enhancer box to boost the darker parts of the video. This is like a standalone 'contrast and brightness' control box that lets you adjust the video signal prior to sending it to the projector. This can sometimes give a better balance between the graphics and the video.

7. Can you consider making the main screen smaller? Remember that brightness drops by the square of the area to be covered, so screen size makes a big difference.

8. I know it may be impossible, but moving the projector closer to the screen is always going to help.

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How big a screen do I need and how far away does the projector have to be?

There are compromises all round when it comes to screen size, but here are some guidelines...

There is no fixed rule for this, but some folk suggest that the height of the screen should be 1/6 of the distance from the screen to the furthest away viewer.
If you try this, you might find that it gives you a BIG screen, and you can probably go smaller. If aesthetics are important and you can push the size of the text onscreen up and have more pages per song, then you might get off with a smaller screen, which would help your brightness levels a lot. (Remember that the same lumens are spread over a larger screen area, so a larger screen will ALWAYS be dimmer than a smaller one, with the same projector).

To give you some guidance, for a smaller audience, say up to 300 people, an 8ft x 6ft screen is often fine.
If you are pushing up to 500-1000 you might want to go to 10ft x 7.5ft, and if you have a huge barn with 1000+ people then you are into the realms of bigger screens still. Remember that there are disadvantages to a larger screen too (see above) so don't go bigger unless you really have to.

Once you know the screen size, and the screen diagonal size in particular
(150in for a 10x7.5 and 120in for an 8x6), then all the user manuals for projectors will tell you what distance the projector needs to be from the screen to fill that size of screen. It varies from projector to projector depending on the lens. To give you an example, our Hitachi CP-X995 (4500 lumens) projectors need a minimum of 5.5m behind a 10x7.5 screen or 4.4m behind an 8x6 screen. Other projectors may vary.

Most smaller projectors have quite wide angle lenses as they are designed for sitting on a conference room table, whereas larger ones are often assumed to be ceiling mount and have longer throw lenses.
You CAN buy special wide angle lenses for most mid-range projectors, but they are VERY expensive and you want to avoid having to do this and put all your money into a brighter projector instead.

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What do I do if my camera postions turn out to be unusable?

You set up a camera position and discover that once you see the positions of people and things on stage, your main shots are being blocked. What do you do?

Well, your choices are

· Live with it – in some cases you may have to, for example during a performance there is often not much option to move a camera position.
· Move the camera – if this is easy to do, it is the least disruptive to what is happening on stage. Performers or speakers may be quite picky about where they stand in relation to each other, so it is best to avoid moving them if possible.
· Move the performer or equipment. In some cases this might be quite simple – moving an amplifier one foot to the left or right, moving a microphone stand etc. However be very careful of situations where you are moving a person around onstage. Make sure they are happy with it, that the lighting guy is happy with it, and that the audio guy is happy with it, and that everyone else onstage is happy with it.

Generally, if you just say to the performer “can you stand a bit further forward’ they will likely forget. Better to move their mic stand to force them to move forward, or put a small cross of white tape on the floor and ask them to make sure they are standing on this. They may still forget, but when they remember mid performance they have something concrete to aim for.

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What is the best order to set up your equipment?

It may seem a bit trivial, but in my experience the order that you do things in can make a big difference between getting everything running for a gig in the time available or ending up running around in a panic at the last minute, or having to run a show without some vital piece of equipment.

If you take a lot of time to set up your cameras, and get all your cables tidied up, and get your powerpoint graphics in order, it won’t do any good if you discover at the last minute that your projector is not working, or that your mixer has a fault.

So here is one suggested order for setup that has some advantages.

1. Set up your screens and projector or projectors first. There are several reasons for this.
- It means you can be sure the projector is working and that the screens are aligned etc. This can be quite a time consuming activity, so it is best done first to ensure that there are no nasty surprises later.
- Often your screen may be at the back of the stage, or above the stage, or near the stage somewhere. It is best to get out of the way of other activities on stage as quickly as possible, so as not to delay other setup tasks.
- Typically you will not have access to the screen or projector once the doors are open and the audience are allowed in.
.
2. Set up your mixer or PPU next. This will let you verify the connection from the mixer to the projector and verify that you can get SOMETHING on the screen. You can use a matte colour from your mixer, or a blank powerpoint slide (pick white, or a visible colour – avoid blue or black, or whatever colour your projector shows for no signal!!) to give you something to set up the projector with. Remember that the setup screen for the projector may not be positioned exactly the same as incoming video or graphics, so it is always best to set up the projector alignment using a real signal.

3. In general set up your most important content playback next. So if you are doing a praise concert with song words make sure that is working all the way to the projector first, and only then start setting up other stuff. If the main reason for having video is to play back a video clip, then check that next and so on.

4. Make sure all your playback content is set up before you go on to any live cameras. I say this because usually at most events the IMAG is a ‘nice to have’ rather than an essential part of the show. If you only got two cameras set up, not three, it wouldn’t be a complete disaster. One exception to this is if you are relaying video to another location. In that case you would get at least one camera set up as soon as possible so worst case you can send a single feed to the other location.

5. Now you can set up your cameras, if you are using them, BUT I would caution against finalizing camera positions until you have seen exactly what the final stage layout will be. All too often I have decided in a camera location on paper, only to discover once the stage is set up that something has moved, or there is a blocked sightline that I didn’t know about or something. So, to save having to move your cameras too often, it is often advisable to wait till the stage setup has progressed to a reasonable stage. If you are limited in your choice of camera locations anyway, then just go ahead and set up and then you have to negotiate with whoever is in charge of the stage layout to address any sightline issues.

6. Only after you have set up everything, and checked all connections should you start taping down cables, unless, of course it is essential for safety reasons. Assume that you will have to move cables at some point before the show starts, and only tape things down when you are sure they will not move again.

Your experience may vary, but at least decide on some kind of order and stick to it, otherwise you will waste a lot of time jumping from one thing to the next.

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How do I get rid of the horrible screen that flashes up when I switch inputs to my projector?

my projector puts up a big blue(black/yellow/whatever) screen every time my switcher switches - can I stop this happening as it looks very amateurish?

You are experiencing the BSOS (Blue screen of sync)!
Maybe. Depends on projector, switch and what you are switching.

The basic problem is that the projector is loosing sync with the incoming video. This is probably happening because you are using a mechanical switcher that is monentarily disconnecting the signal while it switches over from one input to the other - this is very common with consumer AV switchboxes. Another reason may be that you are switching video sources that are not themselves synchronised, that is they do not start each video frame at the same time. Unless the sources are sync'd or 'genlocked' or have both been put through a timebase corrector (TBC) this would be the case. The projector is expecting a sync pulse at a certain time to start displaying each frame of video. If it starts missing a few, it decides there may be no signal present and displays a helpful message to this effect. Unfortunately if it displays this message to the 500 people in your audience just as your speaker is getting to a serious point, then its not that helpful.

There is really only one way to ensure that this never happens, and that is to never stop sending video sync pulses to the projector. This means that something has to keep sending them even when you are switching.
This can be either be a pro switcher that uses electronic switching rather than mechanical switching, or a video mixer that outputs stable sync'd video regardless of what is happening on the inputs.

There is another way to avoid this, which is to see whether your projector can be set up to NOT display this message when it loses sync - some projectors can turn this option off (or just display a blank black screen instead) which is much preferrable.

One other option, if your switcher does switch OK without dropping sync, but the problem is that you are needing to go to a blank screen and are switching to an unused input to achieve this, then you need to have SOMETHING on that input driving sync pulses to keep everything happy. It could be a computer scan converter or TV out displaying a black screen, an old camera with its iris closed, a VCR playing a blacked tape etc. etc.

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My video is too bright - what's wrong?

Everything is connected OK, but the video is far too bright - lighter bits of the image are totally white

If you are using a DA (distribution amp) check that the termination button is in. If you leave the button out (unterminated) the video signal will be double its normal amplitude and blow out all the brighter detail in the image.

Check the settings on the projector - has someone fiddled with the contrast control (contrast = white level)?

If you are using a camera, is the Iris in Manual Iris mode and wide open? Or is there too much gain applied?

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My video has gone all dim - what's wrong?

Everything is plugged in OK, and I am getting a picture but it seems much less bright than normal

Are you using a DA (distribution amp)? If so, is the gain turned down, or is the termination button pushed in? If you have something on the output of the loopthrough, you don't need the termination button in, as the video is terminated by the other piece of equipment.

Is your projector in 'quiet' mode or 'whisper' mode?

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logical fault finding - ten tips for when things go wrong

When everything works there are no worries, but when things go wrong where do you start? When you are under pressure and the screens are black, and everyone is looking at you, it's tough to think straight and the danger is you just grab stuff and start unplugging, and make things work. Here are some possible tips.

There are some basic rules about fault finding that will make it more likely that you will find the fault quickly and be able to work around it in a hurry.

1. Think before acting. The temptation is to dive in and do something, but pausing for a moment to think may well allow you to dive in and do the RIGHT thing.

2. Question your assumptions - there's no point in saying "Well, I KNOW that DVD player is OK" when you have selected the DVD input and are getting a blank screen. Test every assumption by experiment.

Try connecting outputs directly to monitors to see if you get a picture, try swapping inputs - does the fault follow the swap or not?

3. What did you just do? Usually the problem will be that you did something that caused an unexpected effect. Retrace your steps and undo whatever you just did.

4. Actual equipment failure is quite rare - operator error or misconnection is much more common.

5. This is when you are going to REALLY wish you had labelled all your main cables, especially the long ones.

6. If you have actually lost live video during a performance, and need to get something up on the screen quick, then consider removing things in the chain till you get the most direct connection. Ultimately this may mean connecting your VCR output directly to the projector input, at least until you get a chance to do something about it.

7. OK, now down to the logical bit - You start at one end of the chain and work back along checking every connection, every input and output. Once you STOP getting a signal (or START getting one) you know you have found the problem item or cable, and can swap it out or bypass it.
You can either start at the end (projector) and work back, or start at the input (camera) and work forward.
What is especially useful for this is a battery powered LCD monitor that you can plug in as you go down the chain, to check where the signal is getting to.

8. Remember to mark suspect cables or connectors IMMEDIATELY otherwise you will waste time retrying stuff you have already tried.

9. Swapping out gear or cables is the quickest way to bypass any fault. Always make sure that you have spare cables, or have worked out some alternate way of connecting your critical path items. Design your system, then think "What would I do if this gear/cable failed?"

10. Try to only change one thing at a time then test - if you change too many things you won't know what fixed it, or you might fix it, but then unfix it without realising.

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Configuring a computer for graphics presentation

If you have ever had a battery charge dialog box pop up, or a screensaver kick in during a presentation you will know that there are some precautionary measures you should take to set up any computer being used for live graphics display at a VLOBLIVE event... Here are some of them.

A lot of VLOBLIVE gigs need some kind of presentation graphics displayed, usually using a computer.

There are things you can do to ensure that there are no unexpected interruptions to the presentations while they are running. Some are obvious, some are not. Almost all of them have caught someone out at some point!!

1. close all un-needed applications.
Even if you have a super-wizzy fast computer, there is no telling when an app may decide to go and do some CPU-hogging or disk-hogging just as you are doing a smooth dissolve or playing back a media file.

2. close all un-needed system tray applets in windows
Especially news tickers, mail notifiers or anything else likely to pop up a dialog box just at the wrong moment.

3. disable screensavers
Obvious one this, but having a screensaver start, as you are showing a vital graphic is at best amusing, and at worst disastrous. Turn it off completely.

4. disable power management system standby or hibernation
Another obvious one, but you really don't want your machine going to sleep on you. If you are using big media files you will also want to prevent the hard drive going to sleep. This is all set up in the energy saving or power management control panels.

5. disable 'tell me when battery fully charged' dialogs

6. disable on demand virus checkers
let's face it, you're pretty unlikely to pick up a virus mid-gig!! and also disable scheduled virus scans (remember to turn them on again)

7. disable automatic software updates
this is only relevant if you are connected to the internet during a gig.

8. change the desktop to plain black
Just in case you ever fall out of an app back to the desktop while still live on the screen.

9. remove all the icons and files from the desktop
Or at least stick them in a folder, so they are less obvious. Of course you should really be using a dual monitor mode to prevent ever showing this part of the desktop, but not everyone has this luxury

10. Run through ALL the presentation slides at least once before the gig.
A lot of presentation sw caches the files as you present them, so when you first load a presentation file ALWAYS step through all of it before the show, so it has a chance to cache some of the bigger elements. This can make things a lot quicker especially if you have big images or animation.

One easy way to do all this is to set up a special user account that is only used for presentations and that has all these various things configured the right way. This has the added advantage that you can let someone else drive the presentation without worrying about them browsing through your private files or emails.

Make sure this special 'user' is NOT an administrator priviliges

Remember that both in XP and MacOS X you can 'switch' over to your normal user account to do something and switch back, without having to logout and log in again.

Finally if it's not your laptop then make sure you know the login name and password (and BIOS password if required), in case you have to reboot in a hurry. If the owner isn't keen to give you those, get them to create a new user account just for you (or make sure you can grab them during the show!!)

If this all sounds a bit excessive, that's because you haven't faced the embarassment of a jolly dialog box popping up just at the wrong moment yet. You will. It's bad. Best avoided.

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How to cope with non-optimum screen to projector distances?

We've all been there - sometimes there's no time to recce the venue, and when you get there you find that there just isn't the option to put the projectors where they need to be.
What to do? Here's some ideas...

All video projectors have a minimum and maximum distance at which they can fill a certain size of screen. If you go outwith these distances you will either overscan the screen and project onto the surrounding wall etc. or you won't fill the whole screen. Both look pretty bad, but often the projector position is chosen for you, for example if you have to project from the front of a balcony, or have to avoid a pillar, or don't have enough room behind the stage etc.

Of course if you are a pro video team you will have an array of wide and telephoto lenses at your disposal, but back in VLOB-land, this just isn't an option. Most extra lenses or adapters for projectors cost as much as a small projector itself.

So, how to cope with non-optimum screen to projector distances?
I have arranged these tips by the nature of the problem...

If the projector is forced too far from the screen:
In general this is the easier option to deal with.

- Remember that you can go up or down to get less distance from the screen. Sometimes placing the projector on the floor will give you less distance, while not obscuring sightlines. You can use keystone correction to correct for the skewing effect

- Allow the projector to overscan the screen and put black border on graphics or text. This only works if you have control over all the graphics being used, and are not showing any video.

- Use the 'small 4:3 option' in your projector menu to shrink the image. Some projectors (especially those with aspect ratio controls for 16:9 or 4:3) allow you to select a 'small 4:3' mode that shrinks the image to a smaller area. It uses less pixels so you lose some clarity but you don't overscan the screen (and it works for video too)

- Use the 'Picture in picture' option in your video mixer to crop the image. This is dependent on your mixer having this option and being able to use it to crop the image. It severely limits what else you can do on your mixer, so is pretty much a last resort.

- Use centre wipe to mask edges. You can achieve a partial wipe to crop off the edges of a bit of video. This assumes that there is nothing critical that needs to be seen in the border of the image.

If the projector is forced to be too near to the screen:
This is much harder to deal with

- Use a mirror. You may want to experiment with mirrors, but remember that unless you have a very expensive front surface mirror (the silvered layer is on the front of the glass, not the rear) you will end up with a double image.

- Use a smaller screen - obvious, but don't rule out just swapping in a smaller screen. If you are only going to fill part of a bigger screen, why not just use a smaller one.

- Drape the borders of the screen. If this is possible, it can make a neater result.

- turn screen on side and drape the bottom. Remember that all screens can be turned to give a smaller horizontal width, assuming that the unused part can either be hidden or draped.

- Remember that you can go up or down to get more distance from the screen. Sometimes placing the projector on the floor will give you enough distance, while not obscuring sightlines. You can use keystone correction to correct for the skewing effect

If the projector is forced too far off to the side:

- You can use horizontal keystone correction. Normally this will only let you get the projector in line with one or other vertical edge of the screen. Not much but it might be enough.

- pre-warp graphics or video. You can warp the images so that when they are projected they correct for the distortion. If you have to show powerpoint or keynote slides you can export slides to .JPG and warp in a new presentation. Video can be warped in most NLE's but of course you will have to render the whole video clip, once you have worked out the right amount of distortion.

So there you go. All is not lost.

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