Which lens for dolphins and sharks?

I'm about to leave for a trip to Abu Dabbab in Egypt. With some luck we should be able to photograph sharks (Elphinstone) and dolphins (Sataya dolphin reef). Which lenses are the best option for those subjects? I normally use a Tokina 10-17 for wide-angle, but I wonder if that's too wide? I have absolutely no idea how close you can get. Should I add a 1.4 teleconverter for some extra reach, or is the range of Tokina alone sufficient?

I also have a Sigma 10-20 which I bought very recently. But I wasn't able to get a zoom ring in time, so I can only used at a fixed angle. I also didn't have a chance to try it in the water yet. So I'm not sure if it's worth taking with me.

Hi Jef,

I was in Abu Dabbab a few weeks ago, I used only the Tokina 10-17 for wide angle and a 105 for macro myself.

We didn't have luck on Elphinstone, alot of current, 20 liveaboards and a sea full of divers and no sharks. Had the Tokina 10-17 with me, but with so much divers in the water it was far from ideal to get some nice shots.

We did have luck on Sataya, where there was a big group of dolphins. I used the Tokina there as well, mostly on 15-17 mm, Dolphins stayed in the area for quite some time, sometimes getting really close (like 1 meter away). Hardest part was not to include alot of snorkellers. Shot there without strobe's, on a fast shutter speed (1//500) to stop the movement, as those dolphins are really fast. Ended up with mostly sharp pictures. Had to bump up my iso to 400+ in order to get those fast shutter speeds (on a sunny day). I would take the tokina 10-17 lens again if I would go there, (without teleconverter). If the dolphins are there, you will probably get close.

Placed some pictures here, most of the macro pictures are taken directly in Abu Dabbab bay, the wide angle shots are mostly taken on the reefs a few miles of the coast (Abu Dabbab IV and Um Halhala where our favorite's there)

https://www.gaviiformes.nl/2018-abu-dabbab/

good luck and have fun!

Robin