Submarine camera

I have an upcoming submarine tour and it's been a long time since I've done one. Is there such thing as an ideal camera/lens for shooting out the portholes? Would variable focal length trump compactness?

I'm going to assume it may be like shooting through helicopter windows on an aerial tour - so one consideration is unwanted reflections.

A camera/lens with a rubber hood you can put against the porthole may help with reducing them. If not, try to wear dark colors and still get as close to the porthole as possible.

It stinks when decent pictures are contaminated with reflections of pink shorts in the glass...

I can't comment on lens focal lengths as I've never done one before. Don't know if the sub gets right up to cool stuff or if it's 10-30 feet away.