Nikon D780 DSLR Camera (Body Only) - Manual (Page 724)

678 Menu Guide > B The Setup Menu
D Acquiring Image Dust Off Reference Data
• [ Image Dust Off ref photo ] is not available when a non-CPU lens is
mounted on the camera.
• An FX-format CPU lens with a focal length of at least 50 mm is
recommended.
• When using a zoom lens, zoom all the way in.
• The same reference data can be used for photographs taken with
different lenses or at different apertures.
• Reference images cannot be viewed using computer imaging software.
• A grid pattern is displayed when reference
images are viewed on the camera.