Figure 11.107. The same image, before and after applying lens effect.
You can find this filter through Filters->Glass effects->Apply Lens
After applying this filter, a part of the image is rendered as through a spherical lens.
Figure 11.108. “Apply Lens” filter options
Parameter setting results are interactively displayed in preview. Scroll bars allow you to move around the image.
Keep original surrounding: The lens seems to be put on the image.
Set surroundings to Background color: The part of the image outside the lens will have the Background color selected in Toolbox.
Make Surroundings Transparent: The part of the image outside the lens will be transparent.
Lens Refraction Index: Lens will be more or less convergent (1-100).
