I was following the Viewing Angle Article.pdf of Spectracal and doing Meter Distance calculation using the formula D = 2L tan(theta/2), as given in the article. I believe a correction is required in the formula to account for the distance between the point of intersection of FOV lines and the surface of the Meter, as a Meter is not a point object. I thought perhaps I should discuss it here.
Mathematically, the foregoing formula provides the Distance from the Display surface, for a virtual point that is formed by the intersection of the fieldofview lines of the Meter (like shown in the attached drawing). That virtual point may be somewhere along the length of the meter or behind the meter. In order to find the exact positioning of that point from the front end of the meter (the foam pad of i1D3 for example), it will be required to know the diameter of the virtual circle that the Meter measures in Contact Mode. Once we have the Contact Mode virtual circle diameter, trigonometric calculations will give the distance between the point of intersection of FOV lines and the front of the meter. I have i1D3 and i1Pro 2 Meters, and am not sure about the corresponding diameters for these. It would be really helpful if the Viewing Angle Article mentioned that too.
I think that Spectracal should revise the formula D = 2L tan(theta/2) with the correction for the point of intersection of FOV lines of the Meter as mentioned above.
Mathematically, the foregoing formula provides the Distance from the Display surface, for a virtual point that is formed by the intersection of the fieldofview lines of the Meter (like shown in the attached drawing). That virtual point may be somewhere along the length of the meter or behind the meter. In order to find the exact positioning of that point from the front end of the meter (the foam pad of i1D3 for example), it will be required to know the diameter of the virtual circle that the Meter measures in Contact Mode. Once we have the Contact Mode virtual circle diameter, trigonometric calculations will give the distance between the point of intersection of FOV lines and the front of the meter. I have i1D3 and i1Pro 2 Meters, and am not sure about the corresponding diameters for these. It would be really helpful if the Viewing Angle Article mentioned that too.
I think that Spectracal should revise the formula D = 2L tan(theta/2) with the correction for the point of intersection of FOV lines of the Meter as mentioned above.
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