Minimum bend radius for 1/2" EMT?

I'd like to fabricate frameworks for some stands from 1/2" EMT/conduit and I'd like to know how tight of a bend can be accomplished with a shop-made die.

I have benders for doing the electrical conduit wiring bends, but I'd prefer to be able to make 90 degree bends that aren't as wide. The applications would be portable fan or lamp stands, and closer bends mean that the stand can be more compact. I think a closer bend might also be a bit stiffer.

I'm contemplating making a round die with a half-round groove around it, and using it with a smaller rotating die with the same profile. There are numerous manual tubing benders that use this same method.

Would a ram & die-type bender be able to form a smaller radius than a manual tubing bender style?

Thanks WB