Focusing in the dark??

[macroMe]

HI all,
Really simple question with hopefully a simple answer.
I am currently working on getting out of auto and into manual mode on my D90 (incl focussing).
I have noticed that if I try to take a night-time photo in a really dark area the camera doesn't seem able to focus. I understand that there is the AF-assist illuminator but I can't seem to get it together such that I have focus. Does the AF-assist work in manual mode? (yes I have read the manual and it assumes I understand it's techno speak but on this one I am lost)
Is it as simple as turning on a light source to focus and then turning it off again to let the flash do it's work so that there is no ambient light or have I missed the point completely?
Any feedback or advice - I can take all the "oh what a newbie" eyerolling that this question might solicit.
Thanks,
Aug

[wulf]

The autofocus system is independent of the manual control mode. One solution is to focus on something bright at the same distance away and then take your picture (you probably need to flick out of AF mode otherwise your camera will try seeking for focus again). Another is to rely entirely on manual focusing - easier with some lenses than others (the weakness of my 18-55mm kit lens is the focus ring - all my other lenses make manual focusing relatively easy).

Wulf

[RoyL]

I know I use a Canon, and Fuji and Samsung, but I have turned off the AF-Assist. It is next best to useless and is blinding to some people, kids, or animals.

If manual focus is applied then you should be using your eyesight to focus and not rely on little red lights or such to tell you a subject is in focus. And as your camera uses Live View, you should not, just stick to the viewfinder and you will find it easier to focus.

[macroMe]

Thanks so much for the above info. Helps heaps - I was really uncertain about the Af assist in manual mode. I will try adjusting the AF assist (to off) and experiment tomorrow. Will get back and let you guys know how I go. Fingers crossed.
Cheers,
Aug