The 16-85 and 55-300 would make an ideal two-lens travel kit. As Craig says, the 16-85 would probably serve you well in most situations (indeed there are some users here like @TimB64 who have done long trips with just that lens), but I still think you would want to have the tele option.
Originally posted by Lowell Goudge
when i am on vacation i use a 2 zoom set up, and 2 bodies.
This is good advice - probably the best way, and most spouse-friendly way, to minimise time swapping between wide-normal and telephoto. Even a fairly cheap second body would be quite adequate. On a holiday trip (remember them?) to Tasmania in 2017 I mostly left a telephoto lens (55-300 PLM or FA*300, sometimes the DFA 100 macro) on my K-3 and a wide or wide-normal lens (12-24 or 18-135) on the K-S2. There were very few occasions where I regretted using the K-S2 rather than the K-3 (in fact the flippy screen was an advantage at times). The only slight disadvantage was that they didn't use the same battery. A second hand K-5 might be the perfect companion for your K-3 in that sense. (Some argue that it is a better camera for landscapes anyway.) You could sell it afterwards if you don't have a continuing need for one. If the 55-300 is the PLM version, you wouldn't have aperture control if you used it on the K-5, but that should not be a deal-breaker.
If getting a second body is not practical, you should get in some practice at changing lenses on the K-3 inside the camera bag.
Your concern about dust and debris is well founded (it's often an issue in this country). Sand is the worst because it is very abrasive. I would check every day for dust on the sensor (Dust Alert in the K-3 is very convenient for this) and bring a small sensor cleaning kit just in case. If it's likely to be dry, a rocket blower might be sufficient, but I would include some swabs and cleaning fluid too (assuming it's allowed on the flight?).
Enjoy the trip Sam.
Last edited by Des; 1 Day Ago at 02:29 PM.