How far will a projector reach?

[MillburyAuditorium]

Hello everyone,

Well, I can just go try it in person, but figured I would ask first.

Well for a thing our town has "The Chain of Lights", one of the towns clubs want to have a couple movies in our theatre, so I am transforming our theatre into a movie theater for a day, and so, I will be simply bringing my own laptop (Not even going to try to do it on the doggy school computers xD) and find the media cart key and remove the projector from it. ( I'll put it right back where I found it) and set it up in the real of the theatre where the sound board is, so I can hookup the laptop to the board and what not.

Anyways, my question.
The other techy can't make it that day, so im left alone, and I was wondering if the projection will make it to our theatre's built in projection screen on stage, or will the picture be lost. I dont know anything about how projectors work, will it just work from wherever? Mind you the lights will be off.

If it doesnt reach, I need to get some I REALLY trust, and either a 100 foor video cable, or 100 foor 1/4 inch audio wire...

 

[ScottT]

First thing:
What is the distance from the projector to the screen?

If it's one of the crappy little ones that are used in classrooms then it will not go further then ~20 feet. However you can use an online calculator such as this one (Projection Calculator Classic - Throw Distance and Screen Size) to find out the necessary information.

 

[ruinexplorer]

My first guess is that you won't be happy with your image (based off of your earlier posts about your theater). Most likely you have a small desktop projector that may have upwards of 3000 lumens. I don't know how large of a screen that you have, but my guess is that the zoom lens (most likely not one that you can change) will not be capable of throwing the distance that you need (your image from back of house will be larger than your screen). Again, the more you can tell us, the more we can help you. If you can find it, get the model of your projector, the distance from where you want it to the screen, and the size of your screen. Most projector manufacturers will have a distance calculator on their website. This will help you figure a lot of this out yourself.

 

[MillburyAuditorium]

Well its not the cheapest projector, but not the best. It does have controls to move and re size the image, and does have a lens to adjust the size of the image. It is a pretty big screen, almost spanning the entire length of the stage opening, and almost touching the floor to the top of the proscenium arch. I'll try finding the model of the projector.

If it just doesn't work, I am sure we could rent a professional one for the day.

 

[ruinexplorer]

If you have an installed screen, what projector do you usually use? A good rental could set you back $1000/day very easily. I'd rather try to help you use what you have, especially since you are trying to save money for your other project.

 

[fredthe]

In a dark room, you may be OK with your small projector, but it's likely you won't be able to put it at the back of the house, you'll need to move it closer. As was mentioned, check the manufacturer's website for a calculator, or the best way is to just give it a try. Also, don't think that you necessairaly have to fill the screen; a smaller, brighter image is better than a big, washed out image.

Best to have your laptop with the projector. Computer video can degrade over long runs if not done right, but audio can easily and cheaply be run to your mixer. Remember, you can also control the volume from your laptop, and once set (pre-show) you shouldn't have to change it.

If you do need an assistant, consider putting them on the computer... then you can worry about sound and (house) lights.

-Fred

 

[MillburyAuditorium]

We do have an installed screen, but no installed projector, would be great if we did :/ We just use a media carts projector, but it is usually down in front of the stage.
Didn't realize a rental would cost that much : P
Well, I suppose if when I try it out in person it doesn't work I will try making the image smaller like Fred said, and if that is to no avail, maybe have the projector in the some middle of the middle rows. I can use an S-Video cable if image stays better over longer reaches? I know I could get a S-Video cable, all the classrooms have them to go to their TVs.

As for sound im not worried, one of the boards channels is reserved for non perminant inputs, like, our iPods

Well guess I will have to hope for the best ^^

 

[SHARYNF]

the 1000 dollar a day projector is definitely a high end model, probably a lot more complex than what you are looking for


Basically it will come down to size of the image, It does not have to totally fill the screen. Controlling the ambient light in the room is essential. In our local movie theater we now are using a 2 to 3000l lumen projector to display ads before the show. the screen is 35 feet wide projector is 70 feet back and it works reasonably well. For some film festivals we used a different projector 2000 lumens about 50 feet back and that was acceptable also


You don't always need a Christie ;-)))

Basically control your ambient light, and move the projector around to get the best quality image with a reasonable size. Better to have a brighter and clearer image that is smaller than a huge image that is very dim and washed out

Sharyn

 

[MillburyAuditorium]

Thank you sharyn : )

As for ambient lighting, all lights would be off, so, that should be fine.

Great, our screen is fairly large, so can definitely make the picture smaller. Hoping for the best ^^

 

[ruinexplorer]

There's a difference between a 2-3k lumen projector showing ads which are generally brighter and needing less contrast than the average movie. A midline projector at around 4000 lumens (most likely a step up from what you have in stock) will still run you around $700/day (cheaper by weekly rental) one similar to whay you most likely have would run around $400/day. Like I said, we can probably work it out with what you have and save your money for your other project and prices may vary in your area.

Another thing to consider is the sound from your laptop. If you haven't used it connected to your system before, try it out first. Many (not all) laptops have a noise problem with their power supplies and you need to verify it.

 

[fredthe]

I can use an S-Video cable if image stays better over longer reaches? I know I could get a S-Video cable, all the classrooms have them to go to their TVs.

S-video will work in a pinch, but won't be as good a signal. Stick with S/XVGA (whatever the projector supports) if at all possible.

-Fred

 

[MillburyAuditorium]

Yeah, we arent planning on spending money on this besides the movies, So I can work with what I have, I am sure we will be fine : )

And as for noise problems,
I have a little DJ setup in my house, and I do get this noise problem while the power supply is plugged in, its so weird, anyone know why it does this? Gives a hum through the speakers.

I have resolved this issue by plugging the laptop into a different outlet, but still on the same circuit.
: ) Should work at the school as well, will try it out.

 

[MillburyAuditorium]

S-video will work in a pinch, but won't be as good a signal. Stick with S/XVGA (whatever the projector supports) if at all possible.

-Fred

Oh, okay, for some reason I though S-Video quality would be better.

Well, the projector has like, every every input you can imagine. Even audio inputs? Never did figure that one out.
And my laptop has S-Video, the standard blue connector (Don't know the name), and tan. (Don't know the name.)

 

[ruinexplorer]

Oh, okay, for some reason I though S-Video quality would be better.

Well, the projector has like, every every input you can imagine. Even audio inputs? Never did figure that one out.
And my laptop has S-Video, the standard blue connector (Don't know the name), and tan. (Don't know the name.)

The blue one will be commonly known as the VGA connection (D-sub 15) and the tan one will be your DVI connection. DVI will have variations depending on the ability to accept analog, digital, or both. On my laptop, the DVI is digital only and I cannot use a cable that will accept analog signals as well (you will know by the four little holes/pins surrounding the blade connection, if they aren't there then you have digital only).

As for the noise from your laptop, that is a grounding issue. Generally you want all of your audio on the same power to avoid this noise. It sounds like you may be lucky that you can work it that way. I have used other computers where I need to have a Direct Input box between my laptop and the mixer to avoid that noise. Simalarly, the best way to avoid video "hum bars" is to have all of your video on the same power.

 

[SHARYNF]

There's a difference between a 2-3k lumen projector showing ads which are generally brighter and needing less contrast than the average movie. A midline projector at around 4000 lumens (most likely a step up from what you have in stock) will still run you around $700/day (cheaper by weekly rental) one similar to whay you most likely have would run around $400/day. Like I said, we can probably work it out with what you have and save your money for your other project and prices may vary in your area.

Another thing to consider is the sound from your laptop. If you haven't used it connected to your system before, try it out first. Many (not all) laptops have a noise problem with their power supplies and you need to verify it.

I guess we will have to agree to disagree
The ads we are running are infact video clips, and we have run some film festivals again using projectors in the 2-3k region. is it perfect no but with ambient light very low it does work especially if you keep the image size to around 20 feet diagonal. It is worth a try. for our huge screen that is about 50 feet wide we do use a Christie 12k

Personally I would NOT run it from a pc, all the up and down converting etc etc does not help. I would get a dvd player, one with Progressive scan output and use Svideo to make the short run from the DVD player to the projector. Send your audio to the booth.

Again your milage may vary, but try it. Get your projector on the cart and see how it looks and the size of the image and the quality. Most low budget productions don't have it available for 400-800 dollar per day projector rentals.
While a huge screen is nice and impressive but scaling down can work

Sharyn

 

[MillburyAuditorium]

Thanks ruin ^^

Well, I would like to use the laptop because I could just control it a bit better.
Either way, if I can get the projector to work good from the back of the house where the control "center" is, then all connections will be within 2-4 feet.

One video cable out of the laptop to projector right next to me on a stand/cart.

And one audio cable out of the laptop to the sound board.

I will bring the laptop and charger I would be using in advanced to make sure I can get a way to stop the hum if there is any.
It is a problem in the outlets is it not? Or is it in the battery system in the laptop? Because if I simply put the laptop on a different outlet noise goes away, as I said.

 

[fredthe]

On the hum: It's likely an issue with how the grounds on the outlets are wired. (I'm assuming your laptop charger has a ground connection)

On brightness: I came accross this bit of information (though I haven't verified it): The SMPTE standard for projection brightness is 16 footlamberts, with a range of 12 to 22 fL. Now, you just need to get out your calculator and optics handbook

As a bonus question, what's intersting about the footlambert as a unit of measurement?

-Fred

 

[ruinexplorer]

I guess we will have to agree to disagree
The ads we are running are infact video clips, and we have run some film festivals again using projectors in the 2-3k region. is it perfect no but with ambient light very low it does work especially if you keep the image size to around 20 feet diagonal. It is worth a try. for our huge screen that is about 50 feet wide we do use a Christie 12k

Personally I would NOT run it from a pc, all the up and down converting etc etc does not help. I would get a dvd player, one with Progressive scan output and use Svideo to make the short run from the DVD player to the projector. Send your audio to the booth.

Again your milage may vary, but try it. Get your projector on the cart and see how it looks and the size of the image and the quality. Most low budget productions don't have it available for 400-800 dollar per day projector rentals.
While a huge screen is nice and impressive but scaling down can work

Sharyn

You can say that we are agreeing to disagree, but the point that I was trying to get across is that we have many unknown variables here. The setup in a movie theater can be quite different from a traditional theater. First of all, a movie theater usually will have a higher gain screen due to a more direct viewing area, especially in the theaters with smaller screens. As you saw, I have made an assumption as to the brightness of Mill's projector. We don't know how bright it is. Since we are working with unknowns, I definitely support your idea of trying it out with what they have. I also agree that a DVD player (though I'd recommend component to S-video) is a better solution.

Oh, Fred, could you maybe reword your question and post it to the Question of the Day forum?

 

[museav]

I agree that there are too many unknowns, although there shouldn't have to be so many. If the screen and projector are existing then getting the actual screen size and projector model should be possible. And the ambient light level probably could be measured. Of course that still leaves factors such as the loss through the lens, loss due to lamp age, screen material, etc. unknown.

Keep in mind that a composite or S-Video out of a computer and then displayed on a large screen may not look that great. Also consider that if you have a native 4:3 format projector and show widescreen 16:9 movies then you are using only 75% of the total image area the projector displays for the actual image and thus also only 75% of the projector's total output.

Last, I always cringe when I hear about "movie nights" as people too often do not consider the related rights and Intellectual Property issues. Make sure these are covered, don't put the school in a position of liability for their presenting any copyrighted material without appropriate rights or permission.

 

[Lotos]

Last, I always cringe when I hear about "movie nights" as people too often do not consider the related rights and Intellectual Property issues. Make sure these are covered, don't put the school in a position of liability for their presenting any copyrighted material without appropriate rights or permission.

Ditto... I'm surprised it hasn't come up sooner.

This is what qualifies as a 'Public Exhibition'... You know, the things those lovely blue warning messages say that you can't do.

Check here for a good resource: Motion Picture Association of America