“Full Frame Equivalence” and Why It Doesn’t Matter

All that matters to me is will the lens deliver adequate depth of field for what I need.

I`d much prefer to use a M4/3 camera fitted with the 25mm fl.4 than a 5D fitted with a 50mm fl,4 for say a portrait in low light with the lens wide open.

Try and get both eyes in sharp focus on a 5D at fl.4 with a 50mm