Forget about both macro-lenses that you linked to!! These can not be put in front of the Pana-lens!!!
If you want to get closer you need something that is called "close-up lens" - nothing else. And you need one that has a standard thread of 55mm diameter.
The major thing to look after here is that a "camera lens" is not equal to a "close-up lens". A camera-lens has to be attached to your cam-body, whereas a close-up lens has to be attached to the front thread of your camera lens you already have. The Pana FZ-50 does not have a interchangeable lens - so you can only attach a close-up lens
The strenght of close-up lenses is measured in diopters or mm of focal length. The higher the diopters or the shorter (smaller) the focal lennght is the closer you can go with the lens.
The official add-on close-up lens for your Pana is the DMW-LC55E. I cannot find technical data but assume that this one has a focal length of 550mm. So if you zoom the FZ-50 out to the max you can focus at 40-50cm distanc. That should give you some additional magnification on that cam, as with the tele, you get only as close as 200cm. So my assumption
is that this close-up lens gives you 4 times the magnification than you would normally get in your tele-zoom position. But you can use any close-up lens as long as it has the 55mm filter-thread. Canon makes some pretty good ones!
One last advice: As the built in camera lens "looks through" the close-up lens every quality problem of the close-up lens is magnified buy the camera lens. So it is advisable to buy a good quality cose-up lens, not a cheapo for 15 EUR/$. I once did this and immediately sent the close-up lens back...
Thomas (beware: Nikon-fanboy and moderator!) My Lens Reviews
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