Travel and cruise binoculars

Choose 8x42 for most cruise viewing and 10x42 if you mainly want closer looks at distant wildlife from a steady spot. Bushnell's figures for its H2O roof pair show the trade: 409 ft at 1,000 yd for the 8x42 against 305 ft for the 10x42, at 25 oz each.

Our Alaska cruise guide recommends 7x to 10x and warns that higher power magnifies small hand movements.

Yes. TSA allows binoculars in both carry-on and checked bags, though the officer at the checkpoint has the final say (TSA).

If you fly outside the US, check the airline's and airport's own rules as well.

Yes on Holland America, the line we checked. It lists binoculars among optional extras to pack (Holland America), and they are not on its prohibited items list, though ship security can judge any item at boarding.

Check your own cruise line's list before you sail.

Take a compact if the pair will ride in a day bag all trip, and a full-size 8x42 if you will spend hours on deck or at viewpoints. On the makers' sheets, the Nikon Prostaff 7S 10x30 weighs 14.8 oz and the Celestron Nature DX 8x42 22.2 oz.

The 8x42's 5.25 mm exit pupil, against 3 mm for a 10x30, keeps the view brighter at dawn and dusk.

Yes, but each person resets two things. Move the barrels toward or away from each other to match the distance between your eyes (Celestron), then set the diopter dial so both eyes are sharp.

Celestron notes the diopter dial will not need setting again unless another user changes it (Celestron), so note each person's setting on the scale.

Yes, choose a pair the maker calls waterproof. Our Alaska guide advises it because you never know when the weather will turn and lenses can fog, and 11 pairs in this list carry a waterproof claim on the maker's sheet.

For cleaning off salt spray afterward, see whether Windex is safe on binoculars.