Up to this point, the vertical target line has been used to align the lights. The 45° slope line will be used in the fine adjustment to achieve feathering or overlap of the beam. During fine adjustment, the line represents the line of pixels that camera images. On the line it is apparent that target areas are not covered smoothly, as the beam edges may not touch. Disregard the intensity or apparent brightness of the beams and concentrate on "painting" the line from top to bottom with light. Density adjustments will be made during a later step.Note that 3 pairs of lights at 5 mm beam width each will not quite cover the full 35 mm of core depth. If needed, bias the light coverage starting at the top of the core, as this is the most frequently imaged. Sacrificing the deepest 5 mm (level 30-35 mm below the core surface \[-30 to -35\]) in light coverage and focus is acceptable.

These settings illustrate that light angle has more effect on intensity than distance does. However, the target distance of 100 mm must be maintained because it is the ideal distance for light quality without hot spots or banding.Because power settings <100% may prolong bulb life, recommended initial power settings based on testing at F/16 are as follows: 
*\[Author: Do you have recommendations for F/22?\]*