The Moon is probably my favourite photographic target. It's a deceptively difficult target to photograph well, as its contrast levels are so high depending on its phase.
Firstly, the Moon is over 9 times brighter at full moon than at quarter moon. As light is reflecting off the entire surface and coming back at you head-on, there is very little detail to be seen as the entire surface is awash with light. It is far better to photograph the moon at quarter, half, or in between times as the sun is hitting it at an angle relative to the surface, allowing shadows to form across crater tops and mountain peaks. It is far more interesting to photograph at these times.
I'm interested in hearing what camera/lens combination you intend to use. Obviously, the longer the focal length, the more moon will fill your field of view, and the more detail you will capture. Hopefully you have at least a 200mm or 300mm lens. Anything shorter won't give you much moon on the photo!
A couple of simple pointers will see you heading in the right direction.
1) Manually set your camera to its lowest ISO setting - ISO100 or ISO200 if you can. There is more than plenty of light coming from the moon, meaning that you don't have to select higher ISO settings which in turn means less noise in your images.
2) If your camera has aperture priority setting, or you're using a lens that you can manually adjust the aperture on, try to stop it right down to f/11, f/22 or beyond to give you the greatest depth of field that you can. The moon is a sphere, and you'd be surprised how "un flat" it really is - even at near-infinity distances. If you use an aperture that givers you a shallow depth of field, you will definitely notice that either the limb (edge) of the moon is at different focus to the centre of the sphere. Stopping down as far as you can go will alleviate this to a fair degree, and because the moon is so bright you'll be able to adjust your exposure time easily to compensate for the small iris.
3) Given that you've stopped down, the exposure time is next to be considered. As the moon changes phase, the variation in reflected light is huge. What worked yesterday of the day before is suddenly way too bright or dim tonight. Mount your camera on a tripod - do not hand-hold it. At least prop it up on a solid surface at the right angle. Take your first shot at a high speed - say 1/640th sec. Look at the result on the rear LCD. If it is too dark still, easy - go to the next step - 1/500th. Keep going until your image suddenly has nice contrast, and you can see the finer details of the surface "rays" emanating from younger craters such as Macrobius as white streaks across the plain.
4) Focus - now that you can see detail, go to manual focus and start to adjust your focus slightly in between shots, zooming in to 10x on your rear LCD to see the changes from frame to frame. Concentrate on a small feature such as a central crater peak or mountain top. As you exercise focus back and forth, you'll see the feature at its clearest when you reach that best focus position. You can try auto-focus if you have it, but it's usually unreliable in that the camera will most likely try and hunt around and eventually just use the limb to focus on. This isn't optimal when you're looking at the centre for good detail.
5) Some of the newer up-spec DSLR cameras these days have a good feature these days in "live view". Live view allows you to manually focus whilst viewing your target at 10x optical zoom. This is great as long as you're on a good solid tripod and don't have perceptible shake. Live view tends to be a little unsteady because of the high zoom factor which makes it useful in the first place.
6) You can take a stack of quick images as the Moon moves through your viewfinder and cameras field of view given the lens attached. Try and set it up so that the moon enters and then moves across the field, letting you take a quick succession of shots before it disappears out the other side. You can stack these shots in Registax or some other stacking program to average out any noise you've encountered, and to also average out the seeing shift from frame to frame due to atmospheric conditions.
Have fun - it's a wonderful object to capture.
