Constant Height Screen Explained - And a free Excel calculation Sheet!

[WriteSimply]

After having seen a constant height screen myself on a very high end system (close to US$29k for the screen, the projector, the anamorphic lens), I am convinced that it is the best home theater option. Thanks to Deci, he (she?) convinced me that I could avoid all of the mess with anamorphic lens by zooming in the video to fill in the 2.39 screen.

I just can't figure out how to make the zooming in work with most 1080p projectors out there. Like does the zoom has a numbered zoom) as in like from 0 to 100) or is it all trial by error? An auto function would be best.

Anyways, here is a simulated 100" image from a 1080p projector/HDTV - Surf's Up. SPHE release. BD only.




And here is a simulated 100" image from a 1080p projector/HDTV - Die Hard 4.0. Fox release. BD only.




Notice the black bars at the top and bottom that some newbies always complain about. Seriously, we need to educate those newbies.

Owners of RPTVs, plasmas and LCDs have no way of changing the size of their screens. But owners of projectors can - by zooming in on the picture so that only the movie and not the black bars are presented.

A 100" image from a 1080p projector is counted diagonally. So that means for a 100" 16:9 image, the width is 87.2" and the height is 49". A Constant Height Screen is just that: using any aspect ratio, 16:9 or 2.39:1, the height is constant.

Here is a simulated image from a 1080p projector of a constant height setup with a height of 49".



As you can see, the picture is wider but the height stays constant. The width is now 127".

Here is a simulated composite image of Surf's Up and Die Hard 4.0 from a 1080p projector of a constant height setup with a height of 49".



As you can see, that's how a constant height screen is supposed to work.

Anyway, I became obsessed in trying to figure out a way to easily calculate the dimensions needed for the screen given any width, height or diagonal criteria. It took me a while but finally my subconscious math mind figured out the problem. So I created an Excel sheet and it works pretty well. If you don't have Excel, well...

Remember. Rename the file extension to .XLS once you've downloaded the .TXT file. The sheet is protected from accidental cell erasure. You can only enter the values of width, height and diagonal that you need to calculate. If you need to change the cells for whatever reason, you must UNPROTECT the sheet - Tools -> Protection -> Unprotect Sheet.


fuad