Magnitude of extracted sources in the four fields in relation to their flux radius. Sources with eccentricities ϵ ≤ 0.3 are shown as orange dots, while sources with higher eccentricities are shown as blue crosses. Purple boxes show the accepted magnitude values (5 standard deviations from the mean). The sources with ϵ ≤ 0.3 within the purple box in each image are considered GC candidates.