bitcoin address to Hash 160 public key : not consistantly reversible? When I use blockchain.info tools or bitcointoolkit.info tools 

to convert an address, such as 1MCNpVGDY7BGjJyWZL5FJZiaVkQEiuxy8H
to a hash 160 public key : I get dd894dfc0f473c44cc983b5dd462bc1b393f7498

However, if i convert 3MtPk2kf61VepUfwgRjqjC5WeGgxE4rRPS
i get the SAME 160 hash address ie dd894dfc0f473c44cc983b5dd462bc1b393f7498

I am baffled by this. I thought a hash 160 should UNIQUELY convert between it and the Address and back ??? 

I also found other address that convert back fro hash160 to the wrong address....

thanks for any clarification.....

9a278585c51203bca9f0e5c107814ecef6f2aa12
Both of those are correct decoding, the difference is the base58check version byte. 


1MCNpVGDY7BGjJyWZL5FJZiaVkQEiuxy8H has a version byte of 0x01 for P2PKH
3MtPk2kf61VepUfwgRjqjC5WeGgxE4rRPS has a version byte of 0x05 for P2SH


Due to it being a hash, only one of these is typically going to have a valid destination, either a pubkey (P2PKH) or a script (P2SH). If money has been sent to both version bytes of the same hash it is very likely that one amount has been lost.