In addition to posting and tweeting links to my January video tutorial on how to photograph the Moon, I've also been answering several emails asking for additional advice regarding tonight's "super moon." The following is the most recent of one of my replies. The one thing that I think is causing some confusion are the news articles regarding the "time" of the super moon. News clips are saying somewhere around midnight. While that might be the time when it will appear brightest and highest in the sky it is by far NOT the best time to photograph it.
Thanks for your email. I'm hoping for clearing skies tonight as well. I recommend photographing the Moon just after it rises above the horizon, preferable over water if you can. This way you will have the added element of an attractive reflection. This is when it will appear largest and not so overwhelmingly bright that you won't be able to manage proper exposure while including interesting foreground elements. At midnight the Moon will be directly overhead, a bit smaller and extremely bright. The only possible foreground elements would be tree branches but they would be darkly silhouetted.
You will want to use your longest focal length possible, which in your case is 250mm. Spot meter the Moon rather than evaluative metering of most of the frame. I would recommend an ISO setting of somewhere between 200 and 400 and open your aperture wide, such as 4.0 or 5.6. This will most likely provide a shutter speed of somewhere around 1/125 or 1/250 seconds. The more you magnify a sky object with a telephoto lens the faster the object will appear to move through your frame. The good news is that a full Moon is usually so bright - and you can adjust your ISO as you shoot - to the point where you keep your subject sharp and retain detail. Bracket your images, meaning a few frames over and underexposed as well as even exposure. Most likely you will find that your underexposed images will be your keepers.
Most all have fun and move around a bit for creative angles with foreground elements. The best images of the Moon tonight are going to be those captured between 8:00 and 8:30 PM.
Best of luck,