<p>Hi Salil,<br>
Let me tell you my experience. I went with D750, 18-35, 80-400 and 24-120 with D90 as a backup. There were some great suggestions but if I had to change anything, I wish I carried a 28-300 instead of a 24-120 despite the IQ hit. <br>
The landscapes in Antarctica are so vast, 80-400 almost remained glued to my camera, though I got some really good shots the 18-35, mostly on shore. You can check some of my Antarctica shots at https://500px.com/AngikSarkar.<br>
Contrary to most of the experts here, I would strongly advise carrying a superzoom (like 28-300 for FX or 18-300 for DX) glued to at least a backup camera. You worry about the IQ only when you get the shot!<br>
The main purpose of the crappy superzoom lens is for zodiac trips. Penguins, seals and especially whales move really fast though water, the focal length requirement changes so rapidly, you hardly have time to change camera leave alone changing lenses. On one of my zodiac trips, a minke whale decided to check us out. It was swimming so close under our zodiac, I could have probably touched it. By the time I put down my main camera with 80-400 on and picked up the backup with 18-35, the whale had moved further away. There were quite a few of such encounters and missed most shots. <br>
Now for your questions,<br>
1. Again, really easy to change on mainland and on ship but not so much on zodiacs, though I did it anyway.<br>
2. Whatever lenses you take, you will come back with probably the best pictures of your life. I got 400mm and it was great for most cases but for the albatrosses which mostly hung out in the distance.<br>
600mm would have been great there. On land, 400mm was more than sufficient because the penguins come really close to you. The only case where it could have been useful was for the seals which you are not allowed to approach. But, they stay stationary on land, so you could get the shot with 400mm and just crop it.<br>
I wouldn't advise a 150-600 lens as your main lens since 150mm is too long. I got a lot of 'landscape' shots in the 80-90mm range. Also 150-600 lens is too slow. For the flying albatrosses, you may need at least 1/600-1/800 shutter speed on a cloudy day.<br>
3. Read my responses above for lens choices. The purpose of the wide-angle is not a panorama, you can easily do that with stitched photos. The wide angle can give you a great perspective which I love. <br>
Whatever you do, give yourself atleast 3 months/2000 shots to familiarize yourself with the camera. I got a fairly new D750 with me. I shot vigorously before the trip and familiarized myself with it but did not know about some video options which would have made for some killer videos.<br>
Hope this helps.</p>
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