Hi Pat

Not sure exactly how closer PD is, but if you look at the map you will see the reef coming closer to the shore the farther north you go. In terms of visiting the reef, it might make half an hour plus difference in the time it takes to get to the reef by boat. It can get quite rough on the journey (depending on time of year), shorter time to get there makes a difference. However the main reason for recommending PD over Cairns is that IMHO it's a much nicer place to visit and stay. Also closer to the Daintree for an easy day trip up to Cape Tribulation.

The ribbon reefs which include Agincourt Reef which are the most popular reefs visited by boats departing from Port Douglas are 72km from PD.
Comparitive reefs accessed by boats from Cairns such as Norman Reef are 60km from Cairns.
If rough seas are the problem then a mono hull boat like Wavelength would not be my choice of vessel.
You would be better off on one of the larger more stable catamarans which get to their reef sites faster and then have a stable platform waiting for you.

All I'm saying, robbieb, is that reef distances from Cairns or Port Douglas are similar. Certainly closer would be Cape Tribulation and Cooktown.

Wavelength takes approx 90mins-100mins to reach its snorkelling sites, depending on which reef they start the day. A vessel of similar size out of Cairns would be Sea Star (max 30 passengers) which takes just over an hour to get to its first reef stop of day, Michaelmas Cay, then another 15 mins or so to Hastings Reef. Not much in it, really.

Am quite aware of the possibility of bad weather, as are the smaller boat operators, who will cancel the trip if weather dictates.

jw0721 has indicated that she'd like to take the Kuranda Train/Skyrail, this is far more accessible from Cairns or its northern beaches than PD, and whilst the Daintree is closer to PD than Cairns, Cairns is far closer to other World Heritage listed rainforests to the south with the new Mamu rainforest canopy walkway. This can can be self-drive or part of a tour, one of which is www.wooroonooran-safaris.com.au

Having been on both the larger vessels with their own platform and the smaller operations, I much prefer the latter. If you want to snorkel with a real crowd go for the former, not a particularly enjoyable experience in my view. I won't argue re the relative distances of PD and Cairns to the reef, but looking a a map of Tropical North Queensland which I assume are to scale, Norman reef actually measures closer to PD.

Based on half a dozen visits to Northern Queensland and irrespective of reef distances, PD is just a much nicer place than Cairns, but hey all depends on personal preference.

Correct. Norman Reef is closer to Port Douglas, however I am unaware of any tour boats that visit Norman reef that depart from Port Douglas.
Virtually every boat that departs from Port Douglas heads north east to the ribbon reefs.
Whilst the larger boats & the pontoons they visit are not everyones cup of tea, they do offer more options than the smaller vessels, such as semi submersibles, underwater observatories and helicopter joy flights. These options are appealing if there is a non snorkeller who wants to experience the reef without getting wet & for those who are nervous about jumping in off the back of a boat.
The people watching is also first class.