Front VS Rear Projection For Events

Today’s Whiteboard Wednesday episode is all about the projection for events. When organizing an event, chances are, you’ll need a projection of some sort. There are videos, there are presentions, there’s all that good stuff that provides your attendees with more and better content, and your event with extra juice to squeeze.

Tackling projection for events is important so you know what’s you’re looking for. The better acquainted you are with everything it entails, the better communication you’ll have with your AV company. And of course, better communication means a more successful event. So hop on board and join Will Curran, as he guides you through the differences between front and rear projection for events! Are you planning an event? Check out our free Event Planning Checklist and be on your way to planning your best event yet!

Front VS Rear Projection For Events

So whenever you’re looking at your AV quote, you might be able to see a front projection versus a rear projection. You might also see something like F/R on the quote, meaning that the projection screen comes with a front projection and also a rear projection surface that can be exchanged on the screen. This is very common so then that way if there’s a change needed at the event it can be done.

However, always be sure to confirm whether you’re doing front or rear projection with your AV company beforehand. The last thing you want to do is it turns out the layout’s all wrong, you were thinking rear projection, they were thinking front projection, and everything’s all wrong and ruined. Don’t want that to happen so we’re going to talk a little bit about the differences between the two so you can understand it. As always, as I seem to say every time with one of these videos, communicate with your AV company and let them know the difference of what you’re wanting and what you’re planning when it comes to your layout.

Take It To The Front

So let’s start with front projection. This is kind of the typical, everyone knows about it when it comes to a projection screen. Sometimes you also don’t have a choice when it comes to a projector and you might only have front projection available. This is very common with those roll-up screens that pop up very very quickly. They come in eight foot, ten-foot sizes, they’re only in front projection. The reason why is because behind it there’s a pole, obviously, you wouldn’t be able to rear project because there would be a pole in the screen.

Front projection, the benefits of this is that it’s an opaque surface. What this means is that we’re actually projecting from the front, there’s no need for it to be translucent in any sort of way so we want to make sure it looks as good as possible and reflects as much light as possible so it’s a nice bright white screen, 100% opaque. Usually, the back of the surface as well is a dark gray.

All Of The Lights

One interesting thing to keep in mind is that because you are doing a front projection screen and all the light is getting absorbed from the front, you sometimes don’t need as bright of a projector. Again, this is very very minute differences, but front projection screens are slightly brighter than a rear projection screen.

When you are doing a rear projection screen, you are projecting through a slightly translucent surface. What that means is some of the light gets lost when it’s passing through. Think of a tinted window on a car. Not all the light goes through it, and it gets slightly dimmed as it’s going through. So whereas with a front projection screen, 100% of it gets absorbed by the opaque white surface. This might mean that you actually get a little bit brighter of a signal. Very very minute, it’s not going to make a world of a difference. For example, if you have a 3000-lumen projector it’s not going to all the sudden look like a 10000-lumen projector, but it might look a little bit brighter.

Let’s See About Layouts…

What’s interesting though is it’s very important to understand how front projection affects the layout of your room and where your audience sits.  Obviously, the projection’s in front, hence the word front projection, and it’s projecting directly on the screen. What this might mean is there are two different ways that you can have the projector placed.

For example, you can have it on a small little cart, or you can also have it rigged up into the ceiling. Most common and most cost effective obviously is have it on the ground so you’re not paying rigging fees and trusts and all that sort of stuff, but you can also hang it from the ceiling as well. However, if you are placing it on the ground with an AV cart, then if you have people sitting in front of it they could block the screen. This is really important to know because if you are, for example, have a very tight room you might not have the ability to put chairs in front of it. It also means as well if it’s on the ground, it’s going to be right in the midst of all the craziness.

So be careful that when you are deciding where this goes that you have a clear line of sight to the projection screen. A good rule of thumb is just to clear out the space between the screen and the projector and kind of make a nice little box. Obviously, it’s a little bit of a triangle but you want to give a little bit of space around the projector as well so no one bumps into it.

Better For Spacing

However, it also kind of saves you some space as well. So while it can be blocked, you can technically push those screens now all the way to the back wall. Then that way fill in chairs as close as possible, whereas when we get to rear projection, because the screen has to be further out and behind it, it means that you might lose a little bit of floor space. It means you might have to cut some chairs, all that sort of stuff.

So we’re talking about where it has to be. You want to make sure that you’re getting a nice clean shot of it. Obviously, if you’re looking to avoid people’s shadows of their heads walking in front of it, or chairs being in the way, you can always mount the screen up in the ceiling doing rigging but again that introduces additional costs. That’s up to you as the planner.

Now Bring It To The Back (Rear)

Let’s look at rear projection. We are actually projecting from behind the screen. Usually, we call this the back of the house. What’s great about projecting from behind is that it creates just a little bit of a backstage area. This is sometimes really important, and again, how front projection can bring down a downside is that sometimes an AV company needs that backstage area.

Maybe to prep speakers, it could be where the video guys are staying, controlling everything. It also could be an area where they need to store all the empty cases as well. So having rear projection allows you to be able to create that backstage area, and might be necessary.

So if you’re for example doing front projection and pushing it all the way against the wall, it’s important to ask, ” well where are we going to store all the empty cases as well?” Again, as we said, it’s projecting through a translucent surface, which slightly dims the screen but it basically will come through the screen and then the audience can look at it and it looks really good. Hopefully, you have a great projector as well, that’s all dependent on that.

What’s Good, What’s Different

What’s great about this is whereas in front projection if you want to get it where it’s above and clearing people’s heads and everything like that you have to rig it. If it’s on the ground you’re going to run into some issues, with rear projection, the AV company doesn’t have to rig the projector. As long as you’re not putting your screen massively high, you can actually put all the stacks and cases on top of each other, do a simple ground supported truss system. Sometimes even just put it on top of an AV cart and it allows you to put that screen behind there as well. This way you don’t have to worry about people walking in front of it, tripping on cables, plugging in playing their cat videos, all that sort of stuff.

So again, kind of creates a nicer look. In my opinion, I believe this is a cleaner look to an event as well. Whenever you can I always prefer rear projection. The reason why you get that backstage space, I think it looks a lot cleaner, it allows people to walk in front of the projection screens. Plus, as long as you’re using a good enough projector, it shouldn’t worry about dimming the screen as much but we do want to make sure that you know that it does slightly dim the screen and that you do want to make sure that you’re going to need a slightly brighter projector technically.

The Throw Distance

So obviously front or rear projection, the size doesn’t matter, it’s the exact same. The question becomes, when you are doing it, you want to make sure that you are choosing the type of lensing to do this. The way that you do this is understanding throw distance. That’s where this secret is in the throw distance.

Throw distance is the space between your projector and your screen. This is all calculated based on what type of lens you’re using, what type of projector, all these things like that. Your AV company should be able to tell you this number pretty quickly.

They do make what’s called, short-throw lenses. It takes a long throw and makes it shorter. So especially when doing rear projection, we end up doing short-throw lenses for it. However, sometimes when you’re doing front projection if the room’s small enough, we might use a long-throw lens so we can put the projector in the back of the room so we can avoid it being too close and cutting seats and things like that.

This is all possible with the AV company but the thing to keep in mind is again, just always knowing what the distance is and planning, I recommend planning for rear projection to have that space.

Get Padding!

Calculate what your throw distance space is and then what I highly recommend is to add a little bit of padding as well, and what I mean by padding is, for example, you need 15 feet to throw the projector, that’s usually from the front of the projector to the screen itself. That doesn’t include the back of the projector. If you want people to be able to walk behind that projector, if for example, you need additional space to run around, whatever you want to do, always include a little bit of extra space.

For example, if your AV company is requesting 15 feet, it might be wise to at least add three or four extra feet. The reason why I recommend it is just so people can walk behind it. Especially if your projector’s going to be a little bit lower, you want the ability for someone to walk behind it versus in front of it, again, avoiding casting shadows like you do with front projection, even in rear.

Projection For Events: Conclusion

That’s it – now you know about projection for events. This fight has kind of come to an end, but only you can decide who the winner is, whether it’s front or rear. You’ll have to do that yourself but I hope this was really really helpful.

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