Mike
I think it was me who gave you this rule of thumb in a previous post. Most new stadium theatres I've seen have the last row much higher. There are a few problems with this, in my opinion.
1. You get much better sightlines with a lower profile (believe it or not) as long as the risers are designed with variable heights, not equal risers.
2. Your angle of viewing from the back row can be so severe, that people with bifocals for example can't see the picture clearly without considerable discomfort.
3. With a very high back row, the projection booth must be raied higher, leading to extreme downward projection angles (10 degrees or more), with distortion on the picture, or poor focus. Then you have to compensate with tilted screens, etc.
4. The thjeatre is more difficult to access for elder or infirm people (disregarding wheelchairs) who have difficulty walking or climbing stairs.
So, for these reasons, we have established the rule of thumb which we try to follow in all our new-builds.
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