RIB or big boat for whale watching in Reykjavik?

The classic Reykjavík whale boat is a converted or purpose-built steel vessel carrying somewhere between a hundred and two hundred passengers. There is a heated saloon with windows, a coffee machine, a toilet, and two or three levels of open deck including a viewing platform above the wheelhouse.

It travels at about ten knots and works a defined part of the bay, which means it spends more of the trip stationary and drifting than a RIB does. That is not a weakness: a big boat that has found a feeding minke can sit with it for twenty minutes while everybody watches, and the height of the deck gives you a longer view of the water than you get from an inflatable.

The saloon is the thing people misuse. It is there to warm up in for five minutes, not to watch from — nothing is ever sighted through a salt-covered window, and the guide is outside. The people who enjoy these trips most spend the three hours on deck in the right clothes and go inside twice.

Book the big boat if you are bringing children or older relatives, if you want a toilet within reach, if the budget matters, or if you simply want to be able to sit down indoors when the wind gets tiring.

A rigid inflatable carries about twelve people in individual seats you straddle, wearing a full flotation suit over your own clothes. It does twenty knots comfortably, and it covers roughly three times the water of a steel boat in two thirds of the time.

The view is the point. You sit a metre above the surface, so when a minke rolls up beside the boat you are level with it rather than looking down from a fourth-floor window. For photography this is transformative: no railing, no glass, no crowd of shoulders.

The seasickness question is the one that surprises people. A big boat in a short Faxaflói swell rolls, slowly and repeatedly, which is exactly the motion that makes people ill. A RIB is light and fast enough to ride over the same swell, you are outside in cold fresh air the whole time, and you are looking at the horizon rather than at a cabin interior. Most people who dread boats do better on the inflatable.

What you give up is real: no toilet, no shelter, no sitting down anywhere warm for two hours, and most operators set a minimum age. In February that is a serious trade. In July it is barely a trade at all.

Every RIB passenger in this harbour wears a full flotation suit: a one-piece overall with buoyant foam built into it, windproof and largely waterproof, pulled on over your own clothes at the quay.

It does three jobs. It keeps the wind off, which at twenty knots in Icelandic air is the main one. It keeps most of the spray out. And, if the worst happened, it floats you and slows heat loss — which is why crews are firm about zipping it properly rather than leaving it half open because you are warm on the pontoon.

What it does not do is cover your head, your hands or your face. On a RIB those are exposed to a constant twenty-knot wind, and this is where people who dressed for a walk in town suffer. A fitted hat that will not blow off, gloves you can still work a camera in, and something over the lower face on a cold day make the difference between two hours of pleasure and two hours of endurance.

Getting into one takes a couple of minutes and feels ridiculous. Everybody looks the same in them, which is oddly companionable, and nobody photographs well — a small price for being warm at twenty knots.