35 mm Vlads Test Target

USAF 1951 Targets on 35mm Adox CMS 20 Film

This premier product from the Vlads Test Targets collection features ten classic USAF 1951 Resolution Power Charts precisely positioned on a single frame of high-resolution Adox CMS 20 II Pro 35mm film. These targets are indispensable for setting up and calibrating your film digitizing equipment, suitable for both DSLR scanning setups and traditional film scanners such as the Epson V850 or Nikon models.

Instructions for Use:

1. Installation: Insert the test strip or slide into a film holder prior to initiating your digitizing session. Capture the image and review it on your workstation display.

2. Check for Critical Focus: Ensure the entire image—from the center to the edges—maintains sharp focus, exhibiting consistent resolution across all USAF 1951 patterns. Ideally, each chart should resolve the same or adjacent Group and Element number. Siemens stars and individual target strokes should be crisply defined with distinct, clear edges. 

3. Alignment: Confirm that the film holder and camera are perfectly aligned. Inspect for any geometric distortions and ensure that all angles are straight, maintaining simultaneous focus across all target elements. 

4. Aperture Setting: Identify and set the optimal F-stop for peak sharpness across the frame. For instance, an F-stop of 5.6 ½ is ideal for APO Rodagon 4/74 D2x lenses. Deviating from this setting may compromise image quality.

5. Framing: Adjust the frame to cover the desired area, which can include or exclude sprocket holes. Standard coverage without borders typically measures from 23x35 to 24x36 mm, depending on your camera's gate size.

Resolution and Quality: The actual resolution of targets on 35 mm  Adox CMS film is 110 line pairs per mm (lp/mm) or slightly better, confirmed via optical microscopy. 24 MP digital camera typically show resolution 62-69 lp/mm, high-end digital cameras with pixel shift can achieve resolutions 87-98  lp/mm in a single full-frame shot.

Technical Note: It is the camera's pixel pitch (distance between photo sites)  which is mostly responsible for the absolute resolution. The good quality macro lens typically have enough resolving power to out-resolve the majority of sensors, so we we mostly judge and select lenses based on overall uniformity of the image they create.