A device and method for capturing in-vivo images allows for size or distance estimations for objects within the images. According to one embodiment of the present invention there may be provided, in an in-vivo device, at least an imager, an illumination source to provide illumination for the imager, an irradiation source to emit for example a light beam or a laser beam in a body lumen and a processor to calculate, based on image illumination parameter values, an estimate of the size of objects in a body lumen.