I tried searching for the knack quality in previous posts, but nothing came up

So my question is can a character with the knack quality use foci.

A second question I have is does Power foci actually increase your magic attribute or just add to magic rolls?

Any magician can bond any focus. How some ever, not ever focus is helpful to the magician.

For example: someone with the Astral Sight positive quality could bond a spell focus. However, because they cannot use spells, they would gain no benefit from the focus. The foci that would benefit someone with the Astral Sight positive quality are Masking Foci (if they know the Masking metamagic), Power Foci, and Weapon Foci (which it is specified they have restrictions on).

Power foci add dice to Magic tests, not the attribute itself.

Thanks for the clarification

Remember that there is a magic based limit to the number of foci you may bond at any one time...

Aye, number and Force. You can only have a number of foci bonded equal to your Magic attribute, and the total Force of all bonded foci cannot exceed Magic x 5.

So, if your character has the Astral Sight quality (Magic 1) you could have one focus with a Force up to 5.

I want to rephrase my question on this issue are those with Knack and Astral perception considered magicians/mysticadept. Please read pg 84 the last sentence of "Advanced Foci."

My interpretation is nay they would not be able to use Foci.

I've ruled that they can (I'm unclear on the RAW, but I'm not one to get hung up on that), because without it the knacks are kinda Blah. I know the rules caution you about allowing the magic from the knack to increase, but a force 2 fireball is hardly "Killer"

I just say that the character can only bond foci that apply to the sort of magic they can do. For example, a character with a spell knack can only bond spell foci and power foci, but not spirit foci, weapon foci, or any of the fun metamagic foci like masking.

Of course, I also ignore that rule about not increasing their magic attribute, and just rule their hard magic cap is 1 + their initiation grade. But I like more powerful knacks, since I feel the current knacks are overcosted.

I'd argue that anyone with a magic attribute counts as a magician.

This is true Astral Sight does explicitly state they can use Weapon Foci. The Knack quality does not explicitly state they can use them, nor does it state they are magicians. I wonder what the intent of the writers were.

it does state they are awakened though....