Originally Posted by brenster100
so i have a drive encrypted with Serpent-Twofish-AES and am using a key file which is a picture i have edited to make unique is that a secure as i can get it and i am also using a whirlpool hash
I'm not exactly familiar with the algorithms, but I think in principle, as long as your picture is in fact random, then it will make a good key. Also, your "key" might be a file, but keys like that usually go through key schedulers. For example, you can encrypt something with AES 128-bit with a password, and that password is somehow converted to 128 bits. Your picture is going to be a lot more than 128-bits, but it's going to go through some transformations through key scheduling.
Basically, you need to find out how big the keyspace is for your algorithm (how many bits.) If it's too small, then even if you have a random picture, then the key can be found through a brute force attack.
This shouldn't really be a concern since it sounds like Serpent-Twofish is derived from AES, which can use 128-, 192-, or 256-bit keys.