lens options for supermoon

[HDNitehawk]

You will be cropping, moon isn't going to fill your frame. I would just stick with the 400mm without the extender. Shutter speed you when you start getting really slow you will see motion blur from the moon. From memory it seems like this happens around 1 to 1.5 sec. The moon is flat, and you will have plenty of DOF, just use the aperture that is best for your lens. If it is F/8 so be it. On my 500mm it would be F/5.6. Adjust your ISO so you don't get to slow.

The full and eclipsed moon are so bright that it will be hard to get texture. It is easier to get moon detail in other phases.

Here are a few for total eclipse, F/5.6, ISO 800, .5 sec

Full Eclipse 2 36 am by hdnitehawk01, on Flickr

F/13, ISO 100, 1/100, notice I could have went to F/5.6 and had a much faster shutter speed.
Jan 21 Total Eclipse by hdnitehawk01, on Flickr

F/5.6, ISO 100, 1/640

Dec 20 Before Lunar Eclipse by hdnitehawk01, on Flickr