Projector Blog: How do you calculate projector throw distance
How to calculate projector throw distance or the installation point
Finding the instalation point is important to make sure you do not wire up a projector in the wrong position. Every projector comes with a number called the throw ratio which can be used to calculate the instalation point of a projector. Some will even have a range when the projector has some zoom it will be able to be installed in this range between two points.
The throw ratio will usually be a number followed by a colon then another number. The first number represents the distance and the second represents the screen width. For example 1.15:1 if you have a two metre wide image would mean the instalation is at 2.3metre (2metre width X 1.15 ratio = 2.3m)
If it is a range ratio like 1.15 - 1.5 for a 100inch 16:9 (2.13m wide) screen then the calculations would look like this:
|1.15 X 2.13m = 2.45 metres - Closest installation point
1.50 X 2.13m = 3.20 metres - Furthest installation point
Most manufacturers will then advise to round these numbers up and down by 5% in case there is a slight variance among models. After rounding it would be 2.6metre to 3.1metres.