We're designing a home cinema with projector, atmos etc.

We're at the early stages and currently setting out the room size, furniture etc.

Based on a 2m wide (not diagonal, diagonal dim TBC) screen. What would you suggest the distance should be from the screen to the front edge of the nearest seat ?

The projector will be 4k, probably mid level JVC.

I usually say no further than three times the screen's height, so aspect ratio has to be determined. Usually though you would pick the size of screen last (based on viewing distance.)

+1

I use 4 times the height for maximum viewing distance.

The room will determine what size screen you should be using.

Ex. 32' Deep room/ 4= 8' Height

Granted, there are many other factors, but this formula usually gets you the starting point.

If that's as big as the screen will be, save your money for movie tickets.

LOL.

put as big a screen as you can possibly fit. for most reasonable size rooms this does not create a problem. as long as it would be within a comfortable field of view. i do not follow any specific rules other than, as big as possible!!!!!

With a lot of basements I'm dealing with I have between a 7.5' and 8.5' ceiling. I find that this height combined with any thing that has to go on the floor, like a centre channel speaker dictates the height of the screen.

As big as possible.

Craig

I've always felt like the purpose of doing a front projection system is to try to create that emersive feel, just like going to the movies. IMO, that takes at least a 9' wide screen. 8' at the very minimum.

Agreed. At 6' wide you may as well save the trouble and put up a 75" flat panel.

Craig

75" tv = "wow, that's a huge tv!"

6' projector screen = "oh, that's kind of cool"

In the OP's defense, he is talking about a roughly 92" screen, but I do still agree with you.

Thanks All,

You've mentioned the max viewing distance being screen height * 4.

What would the formula be for ideal / best viewing distance ?

What would the formula be for minimum viewing distance ?

We are trying to squeeze in 3 rows of seating.

What do JVC and the screen manufacturer recommend? Have you asked them?

I have used a simple formula when doing initial consults, screen size (diagonal) is 75% - 85 % of viewing distance (eyeball to screen).

My current set up is 110" on 140" viewing distance = ~78%. I could go up to 120 (~85%).

I wouldn't go smaller than this if the goal is an immersive setup.

For your example, I would measure off middle row.

Try this calculator out
[Link: carltonbale.com]

"4x the screen height" is a very rough estimate when you're dealing with fixed screen sizes such as CRTs or flat panel and it fails with higher image element densities. Projection system sizes are customizeable within minimum resolution of the particular manufacturer, eg Da-Lite is 1/4".

Projection screen sizes are based on trying to fill a horizontal field of view, I believe 32 degrees horizonally for SMPTE and 36 degrees for THX. This means that your screen width is calculated using radians and not just a multiple of the height. The human eye's resolution is 1 arc minute, or 1.75mm from a 6 meter viewing distance. This amount changes with the viewing distance, hence rads over linear multiples.

Pick out your seating locations first and then build the theater for the audience. Put the projector as far back in the room as possible to minimize horizontal and vertical light scatter which reflects off the wall, ceiling and floor color to reduce contrast ratio.