Chris Ross

Particularly with the WWL, at the wide end you could open up to f5.6 for a full stop more flash in your photos if you needed it and I would think shooting in the blue that the the Olympus fisheye would also work well at f5.6. The only problem you might run into is the max flash sync speed if you are in shallow water and pointing up where you might want to stop down some more to get the water darker. If the S220 is near as powerful as the YS-D3 you should have no problem, the S220 at 19.6GN vs the YS-D3 at 25 with diffusers is about 0.7 stops difference in power. It seems that the S220 is at least as powerful as the old INON Z240 and some years back people wouldn't have hesitated to use the Z240 for wide angle pelagics, same with the YS-D3, no one would hesitate to use it for wide angle work on a full frame camera at f11-13 range I don't think. Remember these are measured GN by @DreiFish he also measured the HF-1 at GN 31 with diffuser. that is 1.3 stops more power than the S-220 as measured under constant conditions, which is equivalent to opening up from f13 to f8. The thing to remember is the S22- is quite powerful - to get 1 stop more power you need to double the output and that only allows you to stop down one stop. On the m43 camera you don't need to stop down to F11-16 and in practice f8 works just fine even for CFWA. By shooting at f8 you have already recovered the one stop lost by using the S-220 instead of the YS-D3 and if you need faster recycle and you can open up a little with the lenses you propose to use. The last point is that lighting up a whole whale shark is very challenging due to distance it is away, the best you hope for is give it a kiss of light as you are going to be 2-3m away probably at best.

Hi Marco, welcome aboard good to have you here, you will find a quite a few macro shooters here.

Hi all I see that Seacam has just launched tonight a new type of water contact optic seems it is designed to work with rectilinear lenses (16-35 range) and designed to give the same performance as in air. It uses an Ivanoff-Rebikoff lens system Called the Optical Precision Port it uses what looks like a relatively small flat port and a correction lens that is screwed in the front filter threads. Seems like it is very compact and travel friendly, though perhaps not particularly wallet friendly. Here is a link to their website, scroll down and click on the link "12 month practical test for some more details on the optics." A friend of mine Don Silcock did the field testing. https://www.seacam.com/de/optical-precision-port/ Believe Zeiss many years ago developed something similar for the UW hassleblad system.

Agree it has a good chance of working - we'll wait and see what the housing makers do - maybe a R6 II user will take a chance and try a MkIII in their housing for us?

It will be close, comparative views at Camera decision with III copy and pasted over II at 50% opacity on left. https://cameradecision.com/compare/Canon-EOS-R6-Mark-III-vs-Canon-EOS-R6-Mark-II The top dials seem to have moved very slightly. but everything else is very close.

Not many reviews of the MWL-1 around. This one from Jack Connick might be useful, includes some full res images at various f-stops to download. https://wetpixel.com/articles/review-nauticam-mwl-1-conversion-lens-by-jack-connick

Here it is with the adapter attached: and the two parts:

It comes with an M67 adapter that you thread on so that the threads protrude from the end like a regular diopter or filter. I think it shuould be fine with most flips.

Agree that turning up the strobes is your option, for red focus light a red LED I think will be best, red filters let through quite a bit of light in other wavelengths. The flash is so short they often won't react. Same with shutter speed it has no influence in the dark, just set it at you sync speed, you won't record any anything from the focus light at that shutter speed so having it turn off when the strobe fires is not really necessary.

the lens alone gets to 1.4x while adding an SMC-3 gets to to 2.4x, so still an improvement in usable magnification range I would venture. The min magnification without a diopter is possibly greater than 1.4x? . With the older lens you would jump straight from 1:1 to diopter min magnification which might be 1.5 to 1.6x

same as Goretex doesn't really work in the tropics, the humidity and/or temperature inside the suit has to be higher than outside to create a driving force for the water vapout to cross the membrane. Much easier to achieve in cold climates.