how can you convert pass through to direct? i thought it was better to have a direct share as you recieved voting power, therefore why would it be 1:1 exchange
There is no voting power associated with direct ASICMiner shares (unless you own 5000+ shares and get board seat, and even then it's not a vote like with a regular stock). Direct shares are somewhat more secure, as you only have to trust the company, not the exchange and the passthrough-operator. Depending on the PT, a small handling fee may be deducted from the dividend, so you might get more dividends with direct shares.
On the other hand, passthroughs are far more liquid. You can sell PT shares instantly on an exchange, whereas selling direct shares requires you to first find a buyer, negotiate a price, find an escrow, then contact friedcat to arrange the transfer, etc...
As for conversion between PT and direct, the different PTs have different options for this, read through the contract details of the PTs to see what's possible.