If you are refering to Cryptogramma crispa, like many ferns and plants in general, the amount of sun they can take is based, to a degree, on the amount of water they get. Also heat and humidity plays into the situation. Also, if new fronds are exposed to high light levels when they are first developing their structures modify somewhat for the higher light levels, typically by reducing their overall surface area. So, to answer your question; it depends on the conditions.