Best Camera for this?

Unless you want to go mirrorless/dslr in waterproof housing (which I do not recommend) the best option is most likely the TG6.

I have one and it is great, esp for underwater macro. A modest amount of zoom too.

3ricc wrote:

Hello! I will be visiting lakes and the coral reefs in asia and would like to do some underwater videography and photography

I have been looking for a reasonably priced camera for this:

So you need to fill in a bit of info here.

What is your diving experience?    How deep will you go?

Is this a backpacking type trip around Asia for many weeks?   A focused 1 or 2 week trip with lots of luggage?   Something else?

What does 'reasonably priced' mean to you?   And what does "high quality" mean?

For 15k, you can put together a great SLR system that does the best macro possible and also wide angle, shoot in 8k video.   It will also weigh over 30lbs in total.

A more compact APC or 4/3rds mirrorless setup cuts the weight in half, might cost in the upper single digits.

A good compact (fixed lens) setup might be 3-4k.

Unfortunately, overall there is a tradeoff between weight and quality, and price and quality.   There is also a pretty tall learning curve, so if you have no prior UW experience, a simpler setup will have better success on this trip.

I like the TG6 rec as a reasonable cheap try out, and it specializes in macro.   But it has a small sensor and limited manual control.  For a bit more, while still keeping weight down, the LX100 II is a compact with a massive 4/3rd sensor.    Especially good if you want to go casual on lighting/strobes.  But it's better at smallish stuff than true 2" macro subjects.

The Gopro is the 'hero' for lightweight and for easy video, but no one will argue it has anything but a casual shooter for macro.  It is the most backpacker friendly.   If you keep the depth limited, the TG6 can operate without a housing to 50ft, keeping the bulk down.

The used market is not what it once was, but there is potential to save there.

Unfortunately, you are likely to be disappointed. The high quality macro and wide angle pics you see and want to achieve take some diving skill, appropriate specialized gear and practice. The gear includes at least prosumer grade bodies and good lenses, underwater housings and, importantly, one or more strobes and a focus light. Then there is the post processing to remove back scatter, etc. But taking snapshot quality pics to enjoy your vacation is definitely achievable. GoPros are a popular, economical starting point. Moving beyond GoPros takes a significant commitment in time and money.