Just looking for a little guidance about making my projector screen

nightrider1470 · 17 Nov 2013 at 19:44

I have ordered some screen material for a 2.35.1 screen. Have ordered enough to make 9ft in length for my 9ft wall, all though I plan to go under this size as have large floor standing speakers I want at each side of the screen.

My main question is!!...... Is it best to install the projector center of the screen (I do have lens shift) and project a certain movie I know is in 2.35.1 format, Gladiator?, measure projected image on my screen and build my frame the exact size!, would that be the best way to go about it?, or should I max zoom a 16.9 movie? CONFUSED!!

I have a throw of around 12.5ft and I have a Optoma HD87 projector
http://www.projectorcentral.com/Optoma-ThemeScene_HD87-projection-calculator-pro.htm

I also own a Lumagen 3Dmini which I would like to use for scaling the image when in 16.9 format.

Am just confised what is the best way to go about getting it right first time

Thanks so much!!

nightrider1470 · 17 Nov 2013 at 19:54

I wont have to zoom as my Lumagen 3Dmini has some type of scaling option for making the image fit the screen

nightrider1470 · 17 Nov 2013 at 22:23

Thanks Lucid!!

2.40:1 seems much better then.

Could you work out the maths for a 7.5ft and 8ft 2.40.1 screen as it will be one of those sizes.

I just hope there is enough Zoom on my projector to zoom the black bars from 16.9 content.

I have been told to zoom a 16.9 image to fill the 2.40:1 screen then use my lumagen 3Dmini to downscale the image when a cinemascope movie plays. Not sure if that makes sense to you

nightrider1470 · 18 Nov 2013 at 10:40

AlecR said:
Digital scaling will look worse than zooming, but in practice, I doubt you'll see much difference.

Dont underestimate the power of a Lumagen!

nightrider1470 · 25 Nov 2013 at 20:08

lucid said:
I'll tell you how to do the maths and then you can do calculations on any screen width you want.

The aspect ratio of the screen is 2.40:1 That means for every 2.40 inches of width means 1 inch of height. So you're using the times button or the divide button on your calculator.

Screen width divided by 2.40 = screen height.

Convert feet in to inches first to make things simple. So our original 9ft wide 2.40:1 cinema screen measures 108" from side to side. 108"/2.40 = 45"

I believe you're overthinking the whole zoom/aspect/Lumagen thing. It's really quite straightforward if you follow my steps.

1) Get a DVD or Blu-ray disc that is 16:9 i.e. it fills the entire screen area of your TV when the TV is set to 16:9 mode. Try a Pixar animation. They're nearly always 16:9 on the disc. Now go find a film that is 2.40:1

2) Put your projector where it's going to be installed. Set the ZOOM to the BIGGEST picture size. Play that 16:9 DVD/Blu-ray DIRECT into the projector and make sure the projector is on 16:9 mode. DO NOT go via the Lumagen at this stage.

The image you have projecting on to the wall is the biggest image your projector can make. The WIDTH of this image is the WIDTH of your 2.40:1 screen. Mark out the left and right image edges with some tape.

3) Swap the disc for the 2.40:1 film. The image should still fill the width between the tape marks, but it won't be as tall. This is your 2.40:1 screen height. (shown in the diagram by the black outline) if you want to mark the top and bottom edges with tape then go ahead.

If you left your setup like this then any 16:9 or 1.85:1 film would overspill the top and bottom edges of your screen. But you're not going to do that because you have a Lumagen scaler. You'll only use the full area of the screen for letterboxed Blu-rays and DVDs (or rips), so your image will look like this...

4) Now wire in the Lumagen. Play the 16:9 movie again. Set a custom aspect ratio in the Lumagen so that the 16:9 movie fills the height of the screen. The aspect ratio of the film as projected needs to be 16 units of width to 9 units of height. Measure the image height. Divide that figure by 9, and then multiply by 16. This tells you how wide the image should be. If the Lumagen has individual controls for width and height then you can adjust the width so it meets the correct size.

You need do nothing with the projector when playing movies and TV. Just switch the Lumagen between it's standard setting which is what you'll use for letterbox (2.35 or 2.40) movies, and the custom ratio for 16:9 movies and TV.

Thanks for your guide!

Wouldn't it just be easier to project a 2.40.1 BD movie at max zoom, measure it and make it?

Confused why I need to measure a 16.9 movie first?

!!!