Fiji macro: detect bright circles.

detect_pattern.ijm

run("Enhance Contrast", "saturated=0.35");
run("Gaussian Blur...", "sigma=5");
run("8-bit");
run("Auto Local Threshold", "method=Mean radius=50 parameter_1=0 parameter_2=0 white");
run("Invert");
run("Fill Holes");
run("Watershed");
run("Set Measurements...", "area mean standard modal min center bounding redirect=None decimal=2");
run("Analyze Particles...", "size=150-300 show=Ellipses display clear include");