Zoomed Callout Circle to Circle Line

A zoomed callout circle is an annotation where a small circle marks a region of interest and a larger circle shows that same region magnified. The two circles are joined by a leader line, so readers can see a fine detail enlarged without losing its place in the original figure.

Describe the callout to SciFig — for example a small circle on a region of interest connected by two tangent lines to a larger magnified circle. SciFig generates a clean, editable zoomed callout you can position over any figure, instead of drawing the circles and leader lines by hand.

It is usually called a leader line or callout line. In a circle-to-circle zoom, two leader lines run tangent from the small detail circle to the enlarged circle, visually linking the region of interest to its magnified view so the eye follows from source to detail.

Yes. Generate the zoomed callout circle in SciFig and export it as a transparent PNG to overlay on micrographs, screenshots, or schematics, or vectorize it into editable SVG to recolor the circles and leader line before placing it in your figure.

Use a zoomed callout whenever a key structure is too small to read at the figure's scale — such as a feature in a microscopy image, a node in a network, or a UI element in a screenshot. The magnified circle keeps the whole image visible while enlarging the important detail.

A callout circle magnifies a round region and connects it with leader lines, while an inset box crops a rectangular region into a corner panel. Circles suit pointing at one small spot; inset boxes suit larger framed areas. SciFig can generate either annotation style for your figure.