20X objective, part # OKHSL20: To check out the scope under realistic conditions we did acquire some surplus wafers in 6”. The wafers look to be some test versions, maybe for setting up a production run. We will redo these images when we get hold of a wafer in a more finished state and with finer design rules.
The digital camera used is a Moticam 2500 with 5 Megapixel. The camera package did include all adapters needed for this project and then some, no additional parts necessary. All images were captured at 648 x 486. Objective used: Plan APO 20x NA=0.29 WD=31 mm Metallurgical objective.
The relatively low NA of 0.29 is an obstacle at maximum zoom factors. Field of view through eyepieces versus actual size of acquired camera image:
We used 10X eyepieces (FN 20) and eyepiece micrometer (5 mm in 100 units, 0.05 mm per unit) plus reflective stage micrometer (1mm divided in 100 parts, 0.01 mm between line centers) to determine magnification.
Field of view through eyepieces versus actual size of acquired camera image:
By comparing feature size seen through the eyepieces with the captured image we did estimate the image size to be approximately 7.4 mm wide by 5 mm high, much smaller than the field viewed through the eyepieces with 20 mm field diameter. Displayed images are according to Photoshop at 141 x 121 mm (5.556” x 4.764”) in standard 72 dpi . Actual size as viewed on your screen depends on monitor and screen resolution but will be smaller in most cases. In all cases images are considerably larger then the same area viewed through the eyepieces Captured image size was 648 x 486. Color balance was optimized. A strip of a stage micrometer picture - 70 pixels high, acquired at same settings - was added at the bottom. The resulting image was scaled to 400 x 343, resulting in image sizes between 22 - 65 KB. | 
