Hi everyone! So, it's been 11 months since my last thread on Camera Lenses (see https://forums.overclockers.com.au/threads/consumer-lense-lenses-for-travel.1216906/ ) Since then I have traveled to London, Iceland (LOVED IT!!!), Athens (HATED IT!) and South Africa (Incredible). I have taken 1000's of photos with the camera I bought (Canon EOS-750D), learnt about post processing (still a work in progress), and even finally figured out that Lens isn't spelt Lense!!! (Goid I was dense on that one!) I have also bought a few lenses to round out my camera. In my camera bag now is: efs 10-18mm f/4.5-5.6 is stm (Ultrawide Angle) Rokinon 14mm f/2.8 IF ED UMC Lens (for amature astro photography) Stock 18-55mm Canon EF-S 17-55mm f/2.8 IS USM Lens (to replace the Stock) Canon EF 70-300mm f/4-5.6 IS USM Lens (Telephoto) So onto the main point of this post. To out do last years trip, the wife and I will be going on a 12 day 'cruise' from Punta Arenas (Chile) to the Antarctic Peninsula in January 2019. While hesitant of the original purchase of the camera, my wife is totally sold on the money and "bang for buck" I have achieved so far. My current plan is to buy a 2nd body for my wife (a similar model, at least a 600D for the foldable LCD) and possibly a longer length telephoto as a lot of photos will be at a distance from the boat My current thinking is getting a Canon 100-400mm F/4.5-5.6 and possibly an extender (definitely not decided on that one). If I was to get one, considering the extra expense is the mk2 much better than the mk1. I was thinking the weather sealing is important, but then I will have to have a 'raincoat' on the camera all the time (especially on the zodiacs etc) anyway. My other school of thought would be getting a Canon EF 70-200mm f/2.8L IS II USM Lens and a 2x extender., however that would be pretty similar in price (actually more expensive) and would be adding complexity for my usecase. is the f/4 a decent option? I guess the other question is I have spent a fair amount of money on my gear already, am I just throwing money against the wall for the sake of it, or will one of the above options really be beneficial on the trip? I don't mind spending money, but I feel I need to be able to justify it to myself and wife. Having said that, I am itching for some L quality lenses TLDR: Is an upgrade from a Canon EF 70-300mm f/4-5.6 IS USM to a Canon 100-400mm F/4.5-5.6 (mk1 or 2) a decent bang for buck improvement considering my trip. (keeping in mind I am still definantly an amature.