Resolution

Resolution tests were run at 85 inches from the target. An Edmund Scientific lens resolution chart was illuminated with a monolight flash adjusted with a flash meter at f/8. Cameras with Kirk quick release plates and shutter release switches were mounted on a Bogen 3033/Arca Swiss B1 tripod/head combination. Four exposures at 1/250th second were taken at f/8 via cable shutter release at ISO 100 in RAW mode using flash preset white balance. Tifs were produced with Capture One Pro v. 3.6 (300dpi). The central autofocus point was centered over the center pattern for each exposure.

Measurement were made at the center pattern, a middle pattern, and the far upper left pattern on the four exposures. The highest resolution score was recorded. Center-weighted resolution was calculated (60% center; 30% middle; 10% edge). Resolutions were calculated using the method on the chart as follows.

Image lines pairs per mm (image lpm or lp/mm) = lpm resolved on chart X (D-fo) / fo) where fo = focal length of lens and D = Distance from the chart to the middle of the lens.