Before you can start with your measurements, you need to mount the lensTESTER poster, position the siemens stars on it and light the scene evenly.
This part of the manual covers:
Mounting the poster
1. For mounting, we recommend a free flat wall, which offers enough space to your shooting position. The distance between the chart and your camera equipment depends on the focal length you want to use.
2. If wall space is limited, the poster can also be used in portrait format. In this case, the poster can also be placed at a doorway.
3. Hold the poster in the required format at the wall. Try to adjust it very straight and pin or stick it to the selected surface.
Positioning the siemens stars
1. The poster contains marks for the positions of the five the Siemens stars. For easy alignment, the poster offers you grid lines and grey orientation arrows, which are also printed on the separated Siemens stars.
2. Stick the Velcro strips at the backside of each Siemens star. For ideal positioning, we recommend pressing two Velcro snap-fastener together. Stick four related Velcro strips (8 single) to the backside of one Siemens stars using the corner areas.
3. Hold the Siemens star on the sides and in correct way with the grey arrow at the upper left.
4. Arrange the star as straight as possible to a given position of the poster. First press the upper Velcro strips to the poster. This way you still can make little adjustment correction before sticking it completely to the poster.
5. Mount the remaining four stars and the slanted edges the same way.
1. For shooting the test chart and the following analyses, good light conditions are necessary.
2. Pay attention that the chart including the stars is always well and uniformly illuminated.
3. For ideal conditions, use two lamps with nearly identical intensity. Place the light sources left and right with an angle of 45 degrees to your chart.
4. If reflections appears, reorder the lamp positions. Disturbing light sources must also be turned off.
It is possible to illuminate the test chart by the ceiling light. Ensure that the test chart is centrally placed to the lamp so it is uniformly illuminated.
A light meter can be useful for checking the illumination.