I will be visiting Morocco in week's time.
I usually use matrix metering when taking photographs.
However I have read that using the autoexposure (AE) Lock on the Nikon D700 one should use center- weighted or spot metering.
What are the pros and cons of the various metering options in relation to AE Lock?
While trying to answer this, I realized there is no answer.
Most of the times I use Spot meteting with AE-L because it makes a lot of sense. I point the camera where I want to meter the mid-tone (actually I do that with highlights and EC+3 most of the time but the idea is the same) and then lock the exposure in order to compose my image the way I want to. This works wonders :)
However there are perfectly good reasons to use a multi-segment metering system (which Nikon calls Matrix) too. This it typical in street photography where you have a scene which you want to meter properly in its entirety (exactly what Matrix metering is good at) but you wish to wait for a subject to enter the scene. If you knew where that subject would be, you could prefocus and then would simply keep the shutter half-pressed. When you do not, you can lock the exposure and only half-press when you can focus on your subject.
Personally, I never used center-weighed metering anymore. I consider it the ancestor of multi-segment because they both look at the whole scene but center-weighed is less sophisticated. So I either use Spot for to read one spot or matrix for the whole frame.
On a Nikon DSLRs what I do is change the center-weighed radius to be the whole frame. This turns Center-Weighed metering into Average metering which is at least much easier to predict. This is good to use when shooting low contrast scenes such as patterns on walls or floors.
This answer will be for the wrong camera, but it might just help you find the information you are looking for. As @ElendilTheTall suggested this is a very subjective question, so I will just attempt to shed some light on how the system works. With the right info anyone with any camera can go out and check it out on their own.
According to my 5D MkII manual:
When you have found the facts for your camera I suggest you experiment to find what way works best for you. The Nikon term for Evaluative metering is Matrix metering, I believe they are the equivalent, but this does NOT mean that the use the AE lock the same way. I don't have a Nikon manual to check in :D
I can say that the Evaluative metering and AE lock is very difficult for me to use and feels very haphazard, since I have to remember what point the auto focus locked on to before locking AE and recomposing my shop. When I use AE lock I want to know exactly what exposure was locked, so I tend to use the spot metering.
You use spot metering with AE lock when you are faced with a high-contrast scene that may confuse the metering system and want to expose for a particular point in the scene. An obvious example is a backlit subject that is away from the center of the picture you want to take. This technique is also highly useful for shooting with the Zone System.
Spot metering allows you to expose for a particular subject, and locking the exposure on a particular spot, perhaps with exposure compensation, allows you to expose a subject exactly as you want. However, this becomes invalid with evaluative/matrix/multi-segment metering or center-weighted metering because they do not allow for the same level of precision as spot metering.
To do this on my Pentax K-5, I would throw the metering lever to the spot position, hit the AE-L button with the metering spot on the subject, apply exposure compensation if necessary, focus on the subject, and recompose as needed before taking the picture.
