dentrock

Correct. My mistake watching the Sony video and not seeing the scale. Internal zooming is preferable for U/W, if you have a choice.

Extends by what looks like an inch or so as you zoom in - see Sony video. MFD increase to ? 29 cm at tele end (18 cm at wide end). So needs a large radius dome to make use of full range (or just use it at wider end with smaller dome).

And the 38.5 MFD... is there a dome with a big enough radius?! Slightly off topic, but reviews of the new Laowa 10mm FF AF lens are now around. I looked at those by Christopher Frost and Dustin Abbot. Quite complimentary, except for soft-ish corners, I think only at wider apertures; and heavy vignetting, again, more at wider apertures. So... is 130 degrees "enough"? The perennial question! Price is USD 799.

PS: 2 other reasons for me going with Nauticam FF A7CR vs A6700: get away from wretched N85 port system at only 200g weight penalty; and proper screw on optic fibre connections vs cheap push in ones. I was going to go Isotta so I could do my own maintenance, so I emailed them asking if they were going to produce a housing for A7CR. No reply, so I stuck with Nauticam, even though I'll never be able to dismantle (and more important, correctly reassemble) the controls!

Well, it is for me, after reading the specs, even tho I would kill for an AF fisheye. Specs: Min focus 38.5cm (!) Weight: 1.36 kgs Dimensions: D 104mm x L 158mm It comes with a tripod socket which obviously you couldn't use in a housing. How would all that weight go supported by just the lens mount? Imagine bumping it on the dive boat. So, completely useless for U/W, IMO. What do others think?

Mini review: To put a different spin on this, I recently moved from A6400 to A7CR. I chose the latter primarily so I could continue using a couple of crop lenses which have no FF equiv, and still get 26 megas. At the same time I can take advantage of any compact FF lenses that come along. Currently really enjoying a Zeiss 40 CF. Also the Nauticam housing is approx 1 kg lighter than any other Nauticam FF housing. And I could not find anywhere if you can zoom PZ lenses from the A6700 body, whereas I already knew you can with A7CR and other Sony FF cams. In my view the A7CR is thus a true hybrid camera (i.e. hybrid crop and FF)! Having said all that, the improvement in AF is not marked vs the A6400, which either demonstrates just how good the A6400 is, OR that Sony has still a way to go to improve animal eye focus (and tracking even). AF improvement from A6500 to A6400 was much more noticeable. After 10 dives or so, I have reluctantly turned off animal eye, mainly because if it does find an eye (approx 30% hit rate), the focus square becomes so small I have trouble seeing it. And even tho you can set it to pretty much avoid false positives, I just can't be certain what it has found, esp if I am in a hurry. In any case normal AFC tracking medium or small spot is so good, animal eye is not really required. On synch speed, a couple of interesting findings: 1) although rated as 1/160, I get 1/200 with no cutoff with FF lenses. 2) using crop lenses I get 1/250 (but not 1/320 which is next step). None of this bothers me as I grew up with Nikonos 1/60 max and learnt to deal with it !

Nikkor 16mm Compact autofocus rectilinear fisheye prime in VGC. Suits Nikon DSLRs with in-body AF motors (basically all high end Nikon DSLRs). It does not suit Nikon Z mount cameras using FTZ adapter, although I understand an after-market adapter for Nikkor AF-D lenses to Nikon Z mount is being developed. Coverage is 180 degrees diagonal on FX cameras or 107 degrees on DX cameras. Purchased new in the US for USD 1020. No longer available new. Works fine with nice clean optics (one tiny mark on one filter only). Includes 4 rear mount filters as standard, pouch, original box and paperwork. Reason for selling: I no longer own any Nikon cameras. Asking AUD $600. Metabones V Metabones V Canon EF to Sony E mount adapter, near mint. Includes box, case etc. Purchased new. Current new price (Georges Summer Sale) is AUD $870. Reason for selling: works well but I have recently sold the Canon lens I was using with the adapter to another Waterpixel member, who didn’t need the adapter. Asking $500. Nauticam gears and converter – new AUD prices from Scubapix Cairns Australia #19121 N60G-F focus gear AF-S Nikkor Micro 60mm f2.8G. New unused. New price $367.40. Asking $220. #19122 N105VR-F focus gear AF-S Nikkor VR Micro 105mm. New unused. New price $367.40. Asking $220. #19139 N2485-Z zoom gear AF-S Nikkor 24-85 zoom f3.5-4.5. As new, hardly used. New price $352. Asking $150. #19227 TN1017-Z+1.4 zoom gear for Tokina 10-17 lens with Kenko 1.4x teleconverter (suit Nikon, Canon etc.). VGC. New price $352. Asking $175. #83213 M67 to bayonet mount converter. Inc installation tool. New price $137.50. Asking $60.

No weight loss as proposed by the OP, assuming he stays with Nauticam. As soon as you jump up from N85 Sony, housing weight jumps up by 1 kg.... except for A7C / CII / CR housings. I struggled with same problem and opted for A7CR (waiting on housing), rather than A6700. Reason is I figured I could still use some APS-C lenses, while being open to 1 or 2 new FF lenses, such as (perhaps) new Laowa 10mm. Viewfinder is improved over A7C. Also sick of narrow N85 ports. But generally disappointed with porky nature of most FF lenses, cf. svelte APS-C lenses. Having said that, FF 28-60 although slow is compact and sharp as on land although doesn't focus close enough for serious U/W without porky water contact optics. Still, could be OK for mid-water fish pics thru flat port at 60 end... Incidentally, I seriously considered moving to Isotta, so I emailed them asking if they were going to make A7CR housing, back in December. I would have waited for such a housing, since I might have been able to service it myself from all reports (unlike Nauticam). They never replied, which has cost them literally thousands of dollars of my money. Not going to deal with a company like that.

AFS and AFC

Tracking is useful when the eye is not centre frame, and you need to recompose. Locking focus on the eye at the edge of the frame with single spot and recomposing without tracking (or some kind of focus adjustment) is a recipe for slightly out of focus shots (of the eye).

As someone who specialises in fish photography for IDs, and who is busy fooling around with an A7CR (same menus and AF capability as A7RV) while I wait for the housing to arrive, some quick comments: 1. Play around with focusing on the pics in a fish ID book. This will speed up the experience curve, and give you an idea of what the various tracking sensitivity settings do. 2. If you need to turn off (say) animal eye AF tracking, just cycle to human (eg. via Fn menu), and unless a diver pops up, false positive is pretty unlikely. Or customise a button etc. 3. After years of spot focus on various Nikons when I used a 60mm micro 98% of the time, after moving to Sony A6400 and Zeiss 50 I only use tracking with medium spot. I put the spot over the part I want to have focus priority (usually the eye) and let the camera track it as I recompose or the fish moves. You don't need animal eye AF to do this, and my little book tests suggest a very sensitive animal eye AF setting (with the A7CR) may be counterproductive for fish. (Animal eye setting does not work for fish with the 6400, and is best turned off, as it appears to slow down the AF. I leave it on human all the time). 4. Pretty sure the focus motors in the 90 limit what you can do. My Zeiss 50 is a bit faster, and I expect to continue to use it in crop mode on the FF camera. Sony 90 may not be the best choice for constantly moving fish like juvenile wrasses and damsels, since it may not keep up or successfully lock on in the first place. 90 could be good choice for fish which perch (like birds), such as gobies. But for the midwater stuff, better to back off and perhaps use a non-macro lens with terrific AF motors. 5. Check how close you are actually getting to the midwater species. They present the greatest challenge, and no harm in shooting from further away and later cropping extensively. If the focus is spot on, you should still be able to get a pic which allows scale or fin counts on some species. 6. Skill, knowledge of fish behaviour and practice are as important as tech advances. After 50 years I'm still learning and dare I say it, improving, aided by advances in AF technology and sensor resolution.

Interceptor, My point was that Nauticam should provide the info up front to assist dome choice, rather than via instructions that come with the port. I read your dome calculations article carefully and you pull together lots of info which makes an interesting read - for those interested in the detail. Sadly, I think there are not many such people who like to go 'off piste' from the port charts, like you and me! You also make a couple of points which don't tell quite the whole story, but it's not my job to critique. Regarding the N180 which I never intend to buy (and have never even seen one) I was only interested in the detail to be able to cross-check Nauticam port chart recommendations against other possible solutions, using bits and pieces I already have. I accept your measurement of 25mm required extension, and thank you for that. I guess the built-in extension will be in the order of 20-25mm then.

Chris, Aha! Thanks. That explains it. I didn't see the built-in extension in looking at the photo on Nauticam website, and of course they don't bother to mention it, just as they don't bother to mention radii on their website, and are happy to misquote port weights.... Makes you wonder what is their aim. Perhaps push buyers towards those expensive water contact optics?

Chris / Interceptor: clarification requested re amount of extension required for Nauticam 180 WA dome port: 1. The calculator as mentioned by Chris delivers a dome height of 43 if you input R=105 and C=170 (inside dimensions; height is 40 if R=110). 2. Interceptor states in his interesting article on dome port calculations: "I have access to the 180mm dome and I know that the port is actually 8.5cm tall from mount to glass edge because I measured it. This means I need to add 25mm to the extension required." [subtracting 85 from R=110] Now I fully realise that you have to add the thickness of the port mount to the calculator's answer (c. 14mm with my N140), but that is a big discrepancy. 85 vs 43 (+ say 14) =57. Subtracting 57 from R=105 = 48 as the required extension, before you start accounting for EP position etc. So can either of you confirm that only 25mm ext is needed (to account for the 180 WA dome being less than a full half hemisphere), or is it actually quite a bit more ? Thanks!

Thanks again. Wasn't aware of that one. Pleased to see my crude measurements for my N 140 are spot on. Curious about 62mm figure for N180 as it is the same as I calculated for my (now discontinued I think) N 6 inch acrylic WA dome. Will recheck that one. Anyway, great to have the N180 figure and radius as you can then cross-check Nauticam port chart suggestions against any other combos of stuff you might have handy and want to try with a particular lens. And you could use my drawing method if you can't find a published radius for your dome.

Thanks for bringing the calculator to my attention! Easy... if you know the radius. But when I was measuring my Nauticam domes I couldn't find info on their radii - hence the measuring. Can you provide a link?

Some guesswork going on here... Might be a good idea to measure the curvature of your dome, as a starting point for calculating extensions required. This will give you the actual radius, which is info manufacturers should provide, but generally don't. You will need: paper, compass (the sort you used in primary school, not the one on your phone), ruler, pref in mm. Measure the outside diameter of the visible curved portion of your dome. Measure the height at the midpoint. This can be tricky, but within a couple of mm is OK. Draw a horizontal line on the paper and mark the diameter on it, as well as the height above. Find the mid point and draw a vertical line through that. Get your compass and by trial and error, adjust it until its pencil can swing an arc through the three points. Measure from the point of the compass to the height mark and that gives you the true radius of your dome, at least on the outside. You can safely ignore the thickness of the dome for the purposes of this calculation, but you will need to account for the thickness of the metal dome mount, to arrive at a figure to use for calculating a required extension from the port face. FYI, some fisheye domes may not be full hemispheres. Case in point: Nauticam 140 is approx 6mm shy of a full hemisphere... why? I wouldn't mind knowing the figure for where the optical centre is for the Nauticam 180mm dome, if someone cares to measure theirs. I calculated it as approx 42mm behind the port flange (meaning you will need to add approx 40mm of extension to get to the equivalent of using a full half hemisphere dome), but that was guessing from photos, as I don't own one and have no intention of buying one.

Interesting the 36064 is no longer listed on the Nauticam site. It is still shown on the Oz agent's site (Scubapix) at AUD 654 inc GST. I have one which I will be selling soon, at a sensible price. I used it with Sony APS-C lenses, going 'off piste' from the Nauticam port chart. It will be advertised on the correct page...! (probably along with heaps of other stuff inc Canon 8-15, Metabones V etc etc)

Phil, totally endorse your comments, and looking forward to seeing some Laowa AF lenses. Are you sure the new 10mm is for FF, rather than APS-C?

Good luck! I wouldn't swap the Zeiss 50 for the Canon combo...

I own and use the Sony 30, Zeiss 50 and Sony 90, currently with my A6400. I shop tested the Sony 50 when I first bought into Sony APS C (after many many years with Nikon) with an A6500. I found it too slow in the shop and don't like the fact that it extends. My assessment of the others: Sony 30 is fine as general purpose lens, but working distance is a bit short for the smaller cryptic fish which I like to shoot. Depends on the species of course, and your skill as a photographer. I started off using it a lot as a 'go to' lens when you don't know what you will see on a dive, but rarely use it now. My goto lens these days is the Sony / Zeiss 24 with 36125 dome. I never 'bonded' with this lens, but still can't explain why not! Sony 90 works quite well with A6400 but narrow FOV makes following small moving targets quite difficult. Again, depends on your skill and persistence. Also much better in clear water given the longer working distance. Can get very satisfying close ups of larger fish in clear water. If you are into land macro photography, 90 is a great choice with A6400 and an appropriate flash. Zeiss Touit 50. By far my favourite lens. With A6500 was slow to focus, but when it did, results were excellent. I moved to A6400 which has much faster and stickier AF than A6500. The A6400 gave this lens' focusing ability a serious 'kick in the bum', making it very usable for most subjects you would chase with a 50mm lens. Working distance is fine for subjects down to say 30-40mm, bearing in mind you will want some background to give context to a photo. The (expensive) move of camera and housing was worth it for me. The Zeiss 50 focuses significantly faster that the Sony 90, and the focus is stickier. A couple of points to note for best results: 1) I assume you will mostly use AFC, Tracking and (say) Medium spot for underwater. If not, I suggest you read up on the topic. 2) I also assume that you will buy the Zeiss 50 used, as new price is prohibitive for most. In this case, you need to check that the lens has the latest firmware installed, or be prepared to send it to Zeiss for the free upgrade. With the original firmware, the lens prevents the camera flash from firing for a couple of seconds when you press the shutter, rendering it unusable underwater! Google the topic / go to the Zeiss website. Be prepared to be without the lens for a few weeks while they upgrade it, if you need to get this job done. Recent update: I have ordered a Sony A7CR which is FF, after agonising between that and an A6700. However, I intend to use it as a 'hybrid' camera with some of my APS-C lenses, and in particular the Zeiss 50 (because I like it so much, and frankly, there is no alternative (for E mount) in FF (or APS-C for that matter). And I will be able to enjoy the opportunities that FF lenses offer... such as they are! (Not much if anything for underwater macro). Second, when evaluating an A7CII in the shop (no A7CR available at the time) with my Sony 90, I found that I could not detect a difference in AF performance with the 90 on my A6400 vs the A7CII. Could be my test (which comprised seeing how sticky the AF rectangle was in dim parts of the shop) but I reckon the lens motors are the limiting factor on the better Sony bodies, at least with macro lenses.

underwater photography and marine life enthusiast since mid 1960s