Master Poisoner (Ex)
At 3rd level, a poisoner can use Craft (alchemy) to change the type of a poison. This requires 1 hour of work with an alchemist’s lab and a Craft (alchemy) skill check with a DC equal to the poison’s DC. If successful, the poison’s type changes to contact, ingested, inhaled, or injury. If the check fails, the poison is ruined. The poisoner also receives a bonus on Craft (alchemy) skill checks when working with poison equal to 1/2 her rogue level.
Does a poison's onset and frequency change to be of its new type (assuming the poisons matches the default rules for its old type). Almost all poisons appear to follow these rules.
These poisons are delivered the moment a creature touches the poison with its bare skin. Such poisons can be used as injury poisons. Contact poisons usually have an onset time of 1 minute and a frequency of 1 minute.
These poisons are delivered when a creature eats or drinks the poison. Ingested poisons usually have an onset time of 10 minutes and a frequency of 1 minute.
These poisons are delivered the moment a creature enters an area containing such poisons and do not usually have an onset time. For most inhaled poisons, 1 dose fills a volume equal to a 10-foot cube. A creature can attempt to hold its breath while inside the area to avoid inhaling the toxin. A creature holding its breath receives a 50% chance of not having to make a Fortitude save each round. See the rules for holding your breath and suffocation. If a creature is holding its breath and fails the constitution check to continue doing so, rather than suffocating it begins to breathe normally again (and is subject to the effects of the inhaled poison if still in the area).
These poisons are primarily delivered through the attacks of certain creatures and through weapons coated in the toxin. Injury poisons do not usually have an onset time and have a frequency of 1 round.
I ask because the ability in principle is really cool. However, there is almost no point in stabbing someone with Belladonna if its going to take ten minutes to kick in.
Note: You can assume that if frequency changed, duration specified in frequency would as well by the same factor (aka, same number of checks). Mostly though, I'm looking at onset times.