Vignetting ... dealing with
    Vignetting is a condition where the
    camera lens sees the wall around the
    camera barrel. The image taken
    includes the wall thereby forming a
    circle around it. The picture on the right
    illustrates this condition.

    Vignetting is specially obvious when
    using a sighting device and 'picTeur'.
    However, 'picTeur' is optimally
    designed to minimize the appearance
    of vignettes.
    Zooming makes the image bigger and  can completely vanish the vignette.
    The camera barrel is extended more and more as zooming increases.

    Without using a sighting device, the camera barrel is free to extend and
    retract without obstruction. So adjusting the focusing range is not too much
    of a concern. Image is normal subject to filters being used.

    With a sighting device the movement of the camera barrel is restricted
    because it is stopped by the eyepiece of the sighting device. On the
    recommended camera models, focusing range is fixed at a certain point
    which does not allow the camera barrel to move any farther. Focus is
    adjusted at the sighting device. Depending on the distance of the object, and
    the size of the image desired,  vignette may or may not appear.
Use 'picTeur' to
dedications to
veterans of the armed
Digital Camera Lens Guard and Use Extender - Patent No. 9,300,847