Rather than quote people asking Sony questions etc about the chart and suggesting after reading the below that they don't or correcting those posting that the chart is erroneous, I will attempt to briefly explain the Sony throw chart and why it is indeed accurate. Pleased be advised that the actual formulas used to precisely calculate throws for various size screens at the three screen aspects covered by the chart are complex though the numbers shown in the chart are very close but do vary a bit at the extremes. Sony specs the throw range as being 1.27 to 2.73 but the extremes actually vary a small bit based on the various screen sizes at the respective screen aspect. The throw numbers calculated by the chart are all accurate to within plus or minus two inches.
OK. The 1.27 to 2.73 range in the product spec sheet is for a 17/9 (1.888888) or higher aspect ratio screen The chart uses throws between 1.25 and 2.75 or a slightly wider range than the 1.27 to 2.73 given in product spec sheet. This is due to the actual construction of the lens and how it optically operates and the damn complex formulas one must use for absolute precision. The general spec range provides some installation fudge to ensure that one has enough zoom. Good installation practice means staying a small bit away from zoom extremes due to measurement errors and lens variances so a spec of 1.27 to 2.73, a slightly less wide range, is better and safer to use. The chart operates for 16/9, 17/9 and 2.35 screens and the portions of the chart covering 17/9 and 2.35 verify the 1.25 to 2.75 theoretical range.
Things get much more complex for calculating throws for a 1.78 screen and exactly what that throw will do with respect to the full 1.9 chip image. It will throw the portion of the chip image between 1.7777 and 1.888 off the screen. The chart uses a minimum throw of 1.34 and a miaximum throw of 2.92 for a 1.78 screen. Remember a 1.78 source image on a 1.9 chip will not fill the width side to side with an active image. There will be inactive side black bars together totalling approximately 6% of the 17/9 chip width or about 7% more than a 16/9 chip. One must expand this 16/9 image on a 17/9 chip horizontally to fill a 16/9 screen by, you guessed it, 7% and thus by a 7% longer minimum and maximum throw. Multiply the 1.25 to 2.75 range by 1.07 and ta da, you get the 1.34 to 2.92 range used in the chart for a 1.78 screen. Cabish? When your active image exceeds 1,78 on that 1.9 chip, you just zoom longer and shrink that image down a bit so its width fits the 1.78 screen.
I want to thank the forum members for making me think about how to explain all this and for increasing my billable hours to Sony for furnishing them with this explanation for installer trainings.
BTW. The chart for 2.35 presumes one will be using zooming to fill the screen when an aspect between 2.35 and 2.4 is displayed on the 1.9 chips from a 1.78 source frame. In this case the zoom is between 1.9 and your screen aspect and is not as large a zoom as one would need to increase a 1.78 width to a say 2.35.For a 1.78 chiop machine, the zoom increase would be 2.35/1.78 or about
1.33, while for a 1.9 chip, the zoom would be 2.35/1.9 or about 1.24. The zooms get a little large for a 2.4 screen. The chart limits your max lkong throw to where one who still have enough longer throw to decrease the image size back to the 1.9 chip size.
Now if you are not going to use the zoom method but will use an anamorphic, because the approximate horizontal zoom the lens would do is 1.3333 which is too much because the zoom increase you need is only 1.24 or so, you will have to zoom the image down slightly by the projector, so the anamorphic lens's fixed zoom of 1.33 won't overstrech the image.
Tulls. If you follow this you can relax. The machine will work for your application and the chart proves it.
Damn. Its three AM. Sony better pay me overtime.