It would apply to many battles in the 15th and the 16th centuries, as the Polish-Lithuanian Commonwealth won and lost numerous battles fighting the Ottoman Empire. These wars were not a piece of cake for either side and the Polish side lost many battles as well. The Ottoman soldiers were highly-regarded by the Polish side, as they had the capability of carrying on despite suffering big losses. They had a good fighting spirit.
What can I tell you about this photo?
The painter does not have any fvcking idea about Polish winged hussars.
The horses are too bulky\chubby, so they don't look like quality cavalry horses by any standard. The hussar formation is far too loose and the lances are far too short.
This picture is in the wrong topic.