How to Study a Modulation Transfer Function Charts?

Tech

An MTF testing chart talks about the resolution and comparison of a lens from the facility to its edges versus an “ideal” lens that would transmit 100% of the light that travels through it. The comparison of a lens is essential as this works in relationship to lens resolution.

Utilizing an MTF graph is the favoured method for researching lens optical performance as they utilize theoretical equations to plot a performance graph and doesn’t rely upon the subjective point of view, cam features, software application, subject, or other aspects.

The y-axis, or the upright axis, of an MTF chart, gives an idea about the transmission of light via the lens with an optimum worth of “1.0” which would indicate 100% transmittance of the light, although 100% passage of light is not possible because glass is not 100% transparent.

The x-axis, or the horizontal axis, reveals the distance from the centre of the picture in the direction of its edges. So, the “0” in the lower left edge stands for the facility of the lens and the numbers along the reduced axis represent the range out towards the side of the lens in millimetres.

How to review an MTF chart?

 

There are two teams of information plotted on an MTF graph: Sagittal, as well as Meridional lines.

“Sagittal lines,” or the solid lines, represent the different measurements of sets of lines that run alongside a central angled line that goes through the middle of the lens from the bottom left-hand edge to the leading right-hand corner.

“Meridional lines,” or the populated lines, stand for line sets additionally positioned along an imaginary line from the facility of a lens to the side; however, these line pairs are vertical to the diagonal line.

There are two groups of test lines for each Sagittal, as well as a Meridional value: one team or line pair at 10 lines/millimetre and a second group at 30 lines/millimetre. The reduced line sets 10 lines/mm, will typically be plotted greater on the graph than the more difficult fine resolution 30 lines/mm.