TonyP Loc: New Zealand

Just a final couple of comments Cindy. Lots of 'interesting' snorkeling advice here.
I suspect, for safety reasons as much as anything, much of your snorkeling may be on the surface looking down. The water should be crystal clear if the weather has been good before you arrive.
I see you have a dive shop nearby. I really do advise you buy at least the mask and the fins before you go. Fit is everything (and pro advice) of course. I do wonder if they have rental equipment in Tonga, they never did when we were there, but that is quite awhile ago. Anyway, even if they do, the chances of fitting you with what you need would be taking a chance.
The correction lenses I have for my 2 glass mask cost about $800 from memory many years ago. They are the same prescription I had for my spectacles. It takes awhile to have them made so order early if you are planning on them. As I think Hugh mentioned, I would go for small strap on fins with some maybe Lycra socks to stop chaffing if you don't want to wear dive booties. You wont need the power of anything too big (and clumsy for a beginner) unless you want to get somewhere in a hurry (also they will add weight to your baggage). I see you have a lot of experience on the water in your family boat, I envy you the life. I was a PADI diver for many years and a qualified Charter boat skipper. (a pic of our boat https://photogenics.co.nz/albums/Our-Photos/photos/14456643/coastal-aire/?wallpaper ). If you really get hooked on snorkeling and decide to take the experience further some day, come to NZ and try our diving (a bit colder than Tonga tho). The Hauraki Gulf on Aucklands doorstep has some of the best 'safe' boating and diving etc in the world I think.
I forgot to mention the humpback whales. We only saw them once and that was from a distance. (it depends on the season as to how prolific they are). A big life regret for me was never getting to see them closer. But we do have whale watching (Humpback and Sperm) here in NZ and one does get as legally close to them as allowed.
Maybe something else for your bucket list.
Best wishes.

11bravo

My "tough' all weather camera is my TG-6, started with a TG-4. I've never been underwater with it but it is rated waterproof. Small enough to slip in a large shirt pocket. If the weather is bad or I'm out at night and don't want to carry a camera bag, I'll take it. Shoots RAW.

For extra protection, I use a Lowepro Santiago DV 35 Camcorder Bag - Hard Shell Case For Camcorder and Action Video Cameras, LP36372, from Amazon (there are several model numbers, this model works for my TG-6 plus a couple of batteries). They also sell neoprene cases.

I believe the camera comes with a SMALL lens cap, but I highly recommend the aftermarket lens cover. Olympus sells an original for an obscene price, but the knockoff copies work great (I have both and they work the same, twist to open, twist to close. MUCH MORE convenient than the cap that comes with the camera).

On Amazon, search for
olympus tg-6 accessories
and they'll popup.

CindyHouk Loc: Nw MT

Oops....got it...TG6!

CindyHouk Loc: Nw MT

Thanks....our local dive shop won't rent so I will have to purchase, and the local shops in Tonga recommend bringing our own since they have a limited size inventory available. I will be comparing a GoPro to the TG-6 ..not sure yet which one I will get.

CindyHouk Loc: Nw MT

I will remember that about the toothpaste....now I will have to compare the Olympus TG-6, GoPro and the Canon G7! Thanks for the advice!

CindyHouk Loc: Nw MT

Water temp that time of year is around 70 to 75 so a 3 mil is recommended. I will add dive socks to the list as well. I am hoping to get all the equipment I will need by spring so i have a few months to practice in the rivers around here. I am a strong swimmer anyway so hopefully won't have to much trouble getting used to the equipment

CindyHouk Loc: Nw MT

Wow..beautiful boat! Ours is no where near that big but we do spend a large amount of our time on our boat fishing and swimming in the rivers and lakes around here. I am hoping I enjoy the experience of snorkeling and plan on practicing a lot before my trip to make sure I know what I am doing. We will be on the surface looking down more than diving down, so you are right on that.

It might be easier to just get contacts instead of glasses for this trip, that price seems like to much for a week.

Thanks for the advice!

CindyHouk Loc: Nw MT

Thanks! Other people suggested the same camera.

MadMikeOne Loc: So. NJ Shore - a bit west of Atlantic City

Cindy, the first thing I'd do is to ask these questions of the tour company. When I was in the Galapagos for 2 weeks back in 2015, I did lots of snorkeling. Our boat had more than enough wet suits on board for our group of 14. They also provided flippers. The only personal snorkeling equipment my husband & I brought were our snorkels and masks. At first, I was very leery of using a wet suit that wasn't mine due to sanitation reasons. That turned out to be a non-issue. We each had our own assigned suit, and they were all disinfected after each use. At the time of our trip, we both needed lenses put into our masks so we could see underwater. For that, we went to our local dive shop. If you have access to a dive shop, ask them for their suggestions. As for underwater cameras, many on our trip had GoPros. My husband had a little Panasonic that he could use in only one hand, and that worked really well. Unfortunately, that model was already discontinued at the time of our trip!
Enjoy your trip, and share your pics.

alberio Loc: Casa Grande AZ

And I didn't hear any mention of taking a porter along to carry all that gear. I could be convinced to work for scraps of food. Have fun and bring us back lots of your great photos.

jerryc41 Loc: Catskill Mts of NY

Travel light. It makes a huge difference. Olympus makes good waterproof cameras.

https://www.divein.com/diving/underwater-camera/

wdking

I would think the GOPRO on the head would interfer with raising and lowering and clearing the mask. You can get a harness for it to go around the chest and flare up your body for pictures.

I agree with the idea of guide to photo and me to enjoy the tour without trying to photo on my first snorkel trip

smilenangler Loc: The Flood City, Pa.

snorkeled in Aruba they provided life vest so you could just float around, great thing or you'll get tired of treading water

Rich43224

As a diver, I think it would help if you can arrive a day or two prior to your actual snorkeling day(s). Practicing in a pool will help familiarize you with the gear, but it is not the same as being in open water. Waves, current, splashes, will all affect your ability to navigate and to be still enough for taking a photo.

CindyHouk Loc: Nw MT

Already checked and we have to bring our own gear.