Marker Placement Guide

knowing the size and number of markers required for a suitable marker tracking setup is an important part of the setup process, this section aims to help explain the size and density requirements for good quality tracking some general points on marker setup mixing marker sizes is possible and in some cases required markers do not need to be on one surface markers can be at varying heights and planes having a good even distribution of markers across the cambar view is important for optimal tracking having markers clustered only in one small area of the cambar frame will be more likely to cause noise an absolute minimum of 10 markers are required to be viewable at any one time to maintain tracking there is no practical upper limit on the number of markers that can be viewed at one time marker sizing the following table assumes markers are using a material with similar reflective performance as the cincraft scenario marker sheets and that 100% ir strength is being used on the cambar 3rd party markers may have diminished ir reflectivity and will result in shorter ranges being achieved marker size marker to cambar distance 0 5cm 1cm <3m 1cm 0 5m to 6m 3cm 1m to 8m 6cm 6m to 10m 12cm >10m it's possible to mix marker sizes and this may be required, particularly when the camera is able to move between close and far distances relative to the markers marker density the required density of markers is dependent on the cambar distance from the surface the markers are applied to the table below provides a rough indicator of the number of markers required per square metre assuming a "perfect" environment (flat surface, no obstructions to the cambar view) because of this it's often prudent to allow for 10 20% more markers to account for obstructions etc to estimate the markers required multiply the density (using the correct marker to cambar distance) by the area of your studio so for a 10m by 10m studio area where the cambar is around 2 4 metres from the marker surface then (10x10)x2= 200 markers marker to cambar distance (m) number per m² (density of markers) 0 5 15 1 10 2 4 2 4 7 1 >7 0 5 as the distance from the cambar to the marker surface can change drastically during usage a crane going from low to high position for example then it may be necessary to use a mixture of both marker densities and sizes for instance, if there are one or two areas of the studio where the camera is expected to be very close to the markers, then the studio should be configured using the size and density for the " average " usage and the areas where the camera approaches closely can have additional makers of a smaller size and greater density added to them