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Lens selection Decisions

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I've been shooting with a Sony RX100VII in a Nauticam housing, Wet lens WWL-1 with Keldan 4x lights for a year now. While quite nice, I'm moving on an upgrade. First decisions already made, Sony A7s3 and Nauticam housing. Camera in hand and Housing on order. I'm keeping the Keldans. Ah but the lens and port configurations, I think I know but I'm tossing this out to see if I missed something.

First, I shoot video, no stills. I really hate guessing what to set up for a dive, macro, wide angle or fish portraits. I gravitate to fish portraits, simplest setup, IMHO. Another reason I'm changing is I want to shoot with natural light and white balance with no lights, because I'm working at capturing creature behavior and besides bubbles, light also seems to spook those that are indigenous to the deep.  

I see 3 roadmaps, a prime wide angle solution, a macro solution, and a wide angle zoom solution. The macro solution is really its own purpose setup and I will move that direction later, I think, unless someone says its great for fish portraits. Now the wide angle zoom, while offering the greatest UW flexibility it is 6 times the cost of the fixed prime solution. (Sony 28-70mm w/Wide angle conversion-WAC-1). I may go there one day but not his year.

So on to fixed primes, I'm looking at a 28mm f2, 35mm f2.8 and 55mm f1.8. Most info I have gathered say the 55mm is like stuck in the middle, possibly fish portrait only, I understand. The 28mm and 35mm can both be set up to mount a WWL-1(which I own, already) Because of that I'm leaning to the 35mm which if needed the WWL-1 could hauled down below for a reasonable wide angle shot. The 35mm seems to be a bit of a compromise to fish portraits but clearly not as wide angle as the 28mm, but will do a better job of filling frame with the subject.  Ultimately weight is also a consideration, luggage and air travel to distant worlds, well maybe again in 2021 or 2022, sigh. The Caribbean is relatively open and I've been this year and going again in late november. The point being I may not even carry the WWL-1 because of weight and limited use. So my thinking is getting the 35mm with a flat port and jump in.

Observations and thoughts are welcome.

Fair winds and following seas.

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I'm not sure what you hope to shoot with the 35mm lens it's effectively a 45mm normal lens behind a flat port, you can as you say add a WWL-1 but that is a big chunk of glass you keep to keep somewhere when it's not attached to your port.    It should be fine for medium sized fish around 300 - 400 mm long I would think, however it does not focus super close and only achieves 0.12x magnification, so a 290mm long subject would fill the frame horizontally at minimum focusing distance.    I assume you are looking towards primes so you can shoot wider open? 

If I was looking at lenses in that range I'd suggest looking in the direction of the 24-70mm f4 lens which goes with the 180mm dome a fairly compact affordable solution which gives you more reach when you need it for smaller fish and wide enough for a man sized school of fish - but not really wide enough to stray into the issues with poor corners in wide angle domes.  Or you could look at the Sigma ART 24-70 lens which achieves 0.34x magnification filling the frame with a 100mm long subject.

As you previously used an RX-100 I'm sure you are aware of the limitations white balancing Sony cameras underwater. 

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Thanks for the feedback Chris,

Good thoughts to ponder. Yes the WWL-1 is a beast to carry around UW. A 24-70mm is truly my preference for covering a wider variety of shots. My solution for that was remarkably more money than I wanted to spend after the recent cost of the body and housing. But you would have me lean to what I called the wide angle zoom solution (28-70mm), and so would I.  Yet I think, I need to find out if a camera like the Sony A7s3 can truly handle low light without lights and not chase creatures off. (Typically I don’t care to dive more than 15m) and I always know i’ll have at least one Keldan available. And I was hoping to find this out without a major lens/port investment that I might later feel the need to upgrade. Makes me feel I should just go “chips in” and order up the Sony 28-70mm w/Wide angle conversion-WAC-1. Side note really , I prefer to say that with sony lenses from my experience have spot on autofocus  and little to no lens wandering. I also shoot birds in fight and Sony has been a step above in focus performance for me over several other top manufacturers over anything produced in the last 5 years. I was hoping that would be true UW as well. It has been with the little RX100VII but when slicing pixels, its small sensor and color are difficult to manage in post.

Color science, ahh, truly a heady subject, I’ve heard that Cannon is best for UW. But things do change, and the Sony with its low light and spectacular autofocus, IMHO, is worth a try. The significant jump in sensor size and kind of sensor should be a marvelous improvement over the RX100VII. And If I am understanding Daniel Keller right a bigger sensor will “generally” have better color acquisition (CRI). There is hope for a new player in color science. Also ones video skills in post color correction will be pivotal as well, if there is reasonable data space to work with (ie: 10 bit, 4:2:2. (To drift here I’m moving to FCPX for rough cuts and DaVinci Resolve for color correction).

So a question I sort of posed earlier, about the using the Sony 90mm lens, which is a macro, can it be used as a fish portrait lens? I know the more water between the camera and subject is fraught with issues. Maybe I answered my own question there.  But I know I’ll want to shoot macro in the future, just didn’t think it should be my first choice.

Anyway, I do have time to sleep on this, my next dive is on a repositioning live aboard from Miami to the Turks and Caicos at the end of November.

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The issue as I understand it that while you can fix a Raw image in post for colour temperature problems,  video editing does not have the same latitude for correction as you are generally not starting from a raw image so you need to be close.  Good sensors are one thing but if the camera lands you too far from the goal posts you might struggle somewhat.  I guess filters are an option particularly if you are shallow. 

Video is really not my thing I know enough about it to be dangerous- if I might suggest asking in another post  about current performance of the Sony sensors under the conditions you are talking about and recommended approach.  I don't have a feel for how close you need to to colour grade in post.

I find it odd that the 28mm f2 and 35mm f2.8 both are listed as working with the WWL-1 while the 28-70 f3.5-5.6 lens is not as that would be a ready solution for you. 

You might also consider the Zen DP-170 N120 dome port as an alternative to the Nauticam port.

 

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Thanks again for the perspectives,

I am looking at the Zen DP-170 170mm Fisheye Dome Port. it weights a .32 Kg less than the 180mm Nauticam equivalent and is about 400 US dollars cheaper. There port charts do not show a path to the any 24-70mm glass but that, I think, just requires a bit more digging. I am almost there in choosing this first direction to 24-70mm as my entry in FF UW!

About Raw, Chris you are right, RAW provides more room in still work and the same can be said in video. If you can get it. The body I have while expanding the “Data space” recorded to 10bit 4:2:2. It does not do internal RAW. It can do 16bit ProRes RAW video over HDMI at 4K/60P.  Now it does do some amazing high frame rate recording which can be very useful ( up to 120P that is easy to get to via the new menu system)  And I expect to use a lot. Of interest in low light shooting is the peculiar 16000 ISO setting that seems to have virtually no noise, I’m interested in seeing how that may be valuable UW.

<gobiodon>, thanks for the link on the BBC’s use of tech in low light situations. Made me smile about shooting bird behavior at the gloaming of the day. So, so true.

I looked at both of your online portfolios and well, they just made me want to get back in the water, such a beautiful world. Can you mention what lessons you’ve learned shooting macro’s and Chris, specifically what environments or structure UW that indicate that you might find Nudibranchs? I see your in Australia and when the world opens up again, I’m heading to Sydney and and ports north to dive & shoot.

Fair winds and following seas.

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Thanks for that, Nudis can be found in all sorts of habitats and generally on or close to their food source - in Sydney that is mostly on rocky reefs where they feed on sponges, tunicates, hydroids etc.  Apparently nudis in this part of the world are bigger than in other areas like the Caribbean and they can be readily found on the rocks. 

The diving in Sydney is excellent so plan on doing some dives there - the visibility is quite variable and the dive sites are subject to swells so you can't  just dive anytime.  The water is also cold, it's at its warmest of around 20°C in April-May timeframe and dive conditions are mostly good.  Plenty to see underwater including weedy sea dragons, giant cuttlefish, sea horses, nudis etc.

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