I have had a porthole room and the portholes are very large. I would say about 3 1/2 feet in dia. I have never had a navigator veranda, but I would assume it would let in more light because it is a sliding door. That is my guess. There veranda is more expensive thand the porthole rooms.
I've had a Navigator's veranda and seen a porthole room. I would think the portwhole would let in more light. A regular veranda would give you the most.
Because the Navigator's veranda is partially enclosed it does reduce the amount of light coming in (some people like it for that reason, you get a good amount of light but not overpowered by it)
We've done both. For the most pure light I think you would get that with the porthole as the light comes into the room. You get plenty of light with the navigator verandah but it is more defused since you have the balcony space between you and the room.
We prefer the navigator verandah even over a regular verandah due to its privacy, furniture, and that you can get some shade out there as well. It is one of my favorite places to go with a good book.
Edited to add - you may get more light from the navigator verandah on the Wonder. The porthole there is oval. On the Magic it is round just like the porthole in the cat 8 or 9.
What!! You're not one of the people that leave their curtains open while in port and wander around the room neked and clueless that they're giving everyone on the next ship over a "free peep show"
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