Originally Posted by DrFaxe
since the test didn't work out for me, one can calculate the distance from the screen, here's the info for your set:
Model: i1D3 | Full Width Half Max Angle (FWHM): 10.5 degrees | Total Light Termination Angle (TLT): 15.9 degrees
Active screen area:
48.04 inches (width) by 26.99 inches (height) - assuming a 55.1 diagonal of active area
Lumagen large pattern 11.11%: 16.01 inches (width) by 9.00 inches (height)
Lumagen small pattern 1.56%: 6.00 inches (width) by 3.37 inches (height)
Lumagen large pattern 11.11%: TLT distance of 32.21 inch (81.81 cm), FWHM distance of 48.95 inch (124.34 cm)
Lumagen small pattern 1.56%: TLT distance of 12.07 inch (30.66 cm), FWHM distance of 18.34 inch (46.59 cm)
I always use the TLT distance as a maximum reference point, but I actually move the meter closer, which means you are reading the area inside the patch - all values above are indicating positions of the meter that will read the exact full patch to it's outer boundaries...
e.g.: I use large Lumagen patterns on my 65VT50 which are 11.11% - if you can only adjust the size manually, like in LS, see physical size above for your screen... but even with 11.11% on my 65" I go as close as 12-15" for readings, I could go further away with that pattern size... Problem is one must also position the meter correctly in vertical and horizontal position (all values above are for dead center / center), so moving closer to the screen eliminates problems that could occur b/c of that...
since you have the smaller 55", 10-12" for the i1D3 should be fine with large Lumagen patterns, the i1Pro should be further away than the i1D3...