AVIXA CTS Study Group
Viewing Area Plans
I am referring to ANSI/AVIXA V201.01:2021 standard, Annex A — Examples of Viewing Area Plans, Page number 17.
What is the negative number in position 1 (-617mm) and 2 (-610 mm), for that matter all the five positions. Could someone please help me?
I'm going to double check with an SME that worked on the standard (and will follow-up post if different) but looks to be elevation difference with respect to center line of display (in elevation). So, under drawing note of "Vertical Display Information:" which then gives "Center Line Height of Display 2076mm (81.75)" you'd subtract value (position 1) of 617 mm (24.31") to define the elevation axis, which then combined with the plan view axes (also shown) define measurement point for each location.
Hello Greg, I am sorry to say that I didn't understand it at all. Could you please teach me, I am ready to learn.
Hello Greg, After a deep thinking and going through your response, I can understand that, these are the measurement points (from height where measurements were taken below / above "Center Line Height". This approximates to 2 feet or 600 mm standard, because the display height is 48" above floor .
For Page 17, Figure A.1 Classroom example, it is almost 2 feet in all the five locations.
If you observe the Page 18, Figure A.2 example, position 1, 2 and 3 have similar 2 feet measurements, but the viewing positions 4 and 5, the eye positions, may be seated in raised chairs, above the Center Line, which are 5 and 3 inches respectively (above Center Line.
A similar, 2 feet, measurement is reflected in Figure A.3, for front row and 1 feet below Center Line for rear row (which might have been raised one feet compare to front row.
The slight variations may be due to adjustable chair heights or seats. The tester may be seating while taking the reading and the height from his eye or meter to center line is recorded. Just also observe , Session 4.4.4 Equipment Requirements, "point g" which says " A tripod to eliminate human factors of inaccuracy in test measurements".
Please correct me if I am wrong.
Correct - that is how I read it as well. But have also taken note, based on your post, to have the standard's task group look to make the example(s) a bit more clear to interpret - the next time the standard is due for maintenance/revision.
Thank you, Greg. Appreciate your response. It would be good if there are explicit notes. Otherwise, it would be difficult for the user to conclude on such things.