Big, Perhaps you're longer in the legs and shorter in the torso than I. Sitting down, I got measured at 30" chair to eyes sitting up. I'm only 5' 8". At least I was when I was younger! But I didn't get measured reclining until just now. I got 27". It was a slight to moderate recline. According to the Palliser web site, the chair I'm looking at has a seat 20" off the floor. That's how I got my initial 50", but 47" is still well above your rule of thumb. I'll have to find a way to get myself into a more realistic recline and have someone measure. But with your numbers, I would guess my sight lines would be unobstructed.
J_P_A, Thanks for your thoughts. I've been browsing your build thread and your analytical nature shines through at full volume! It is both a blessing and a curse, this perfectionism gene. I'm sure I'll spend the next couple of days finishing your thread.
I believe the reason I'm having trouble with figuring out the seating is two fold. You are absolutely correct that 90% of the time it will be me and a couple of others in the family, tops. And that's only when I can't slip down and enjoy the space in peace and quiet! :-) But I anticipate having people over at least once or twice a month to watch a game or a flick. And with the kids getting to be teenagers, I'm encouraging them and the friends to hang out at our home rather than have them lord-only-knows-where doing lord-only-knows-what all around town at everyone elses' houses. Thus, the full basement renovation with lots of space for teen recreational activities. So I want to have capacity such that I'm not constantly dragging extra chairs in and out of there.
But I think the primary reason I'm having problems is the shape of the room. Because of the octagonal shape around the screen wall, I'm hexed (pun intended) by the contrary reality that in order to optimize the viewing angles at the seating distances available for the 3 rows, I have to push the screen wall farther back towards the rear wall which is narrower and thus will only support a smaller screen for which I don't need the vertical distance. Viewed from the opposite perspective, as I try to get a bigger and bigger screen in there (I've often heard that the most common thing people wish they did differently was put a bigger screen in the room, and conversely, nobody every complains that their screen is too big!) I have to pull the screen wall forward into the theater thus shortening the available distance from the front row of seating to the screen and making the viewing angles untenable.
This dilemma is further compounded by the fact that I was flip flopping between 2.35 and 1.78 screens and I was trying to get a sense of how close I could get the family to sit to the screen by sitting them various screen width ratios away from our 55" (diagonal) Samsung LED TV. I really wanted a 2.35 screen as I figured that was really the way to get impact, but I came to the conclusion that a 2.35 image on an identical width 1.78 screen would be the exact same sq. footage of image as that image on a 2.35 screen. But 1.78 images are significantly bigger on the same width 1.78 screen vs. on a 2.35 screen. While playing 2.35 material on the Samsung, I was getting complaints that only started to diminish at 1.2 screen widths and became tolerable at about 1.4 screen widths. Watching 1.78 material needed 1.5 screen widths to be acceptable and she really likes closer to 1.8 screen widths. So 1.78 would have been intolerable at anywhere near the distance I have available (if I went with 3 rows) for the front row. So I was resigning myself to two rows. With a two row room design, I figured I could get 14'-15' of depth so I settled on a 10' screen width. At that width/distance, it seems you are more limited by the height of the image than the width. But it is what it is.
I think I've come to some peace with my current seating arrangement primarily as a result of actually sitting in a theater and watching part of a movie with my wife (in a Magnolia of all places) that had a 10' wide 2.35 screen with the first row of seating at 10' and a second row of seating at 13' on a riser. I was astounded when my wife found the image to be acceptable at 1 x screen width. Large, but acceptable. Now we were talking. I think I calculated viewing angles with their setup (10' away from 10' wide 2.35 screen) at 53 degrees horizontal and 24 degrees vertical. So as long as I stayed underneath those boundaries, I should be OK. At this point, my analysis starts with the fact that I found a 120" diagonal 1.78 image at another local AV store very satisfyingly big even at a distance of 15' and that sort of jives with the limits of my wife's tolerance. A 120" diagonal 1.78 image has a height of 59". So I worked backwards from there to find out that a 2.35 screen with a height of 59" has a width of 139" (or about 11.5'). This, I figured, would be the good enough size. A screen that I was looking at adds 7" to the width of the viewing area so I'd be at 146". I'm budgeting a maximum of 13.5' for the screen wall (or 162") which still gives me a little more than 12' to the first row eyes. So now I'm at less than a 1:1 ratio of screen width to viewing distance so I should be all set with viewing angles of 52 degrees and 23 degrees - just under what was experimentally found to be acceptable under real life conditions. Once reclined, the viewing distance will increase a few inches as well to make things even better!
The only "drawback" is that the second row must be a non-reclining sofa as I will only be able to budget about 4.5' for that row.
Another positive for getting the front row up a little closer to the screen than under my 2-row scenario (where the seating would be at 14-15' from the screen), is that my side surrounds can realistically only go back to about 14' without getting too close to a corner. With this arrangement, I can put the sides at about 13.5', so just behind the plane of the first (prime) row seats.
So what helped me finally come to peace with a seating/screen combination was actually being able to sit in a theater to watch a movie and discovering that 1 x screen width viewing distance was acceptable combined with deciding that a 120" diagonal 1.78 image is good enough. Yes, the 120" wide 1.78 screen is taller (68") but even at 59", the screen is at the upper limits of where I need to be to get my sight lines acceptable. A taller screen would make the sight lines that much worse.
It seems that once those two factors were set (screen size/mounting height and viewing distance), everything else is falling together much more easily. I'm encouraged by Big's assessment that my height estimates are generous as my sight lines were the other primary factor under consideration.
Now I have to figure out what projectors will light up that screen well. Another reason for going with the wider aspect ratio is that I have a niggling suspicion that native 2.35 panels will be more widely available and more affordable as time goes on. That would then get rid of this whole anamorphic stretch vs. zoom debate where there seems to be no right answer.