dentrock

So I have just got my Laowa 10. And since no-one else has volunteered an EP measurement, here is my estimate: 61mm from lens flange to apparent position of diaphragm, when viewed from the front of the lens (just below the blue ring on the lens). Others should check this and let us know what they think, as I found it reasonably difficult to estimate for this lens; but I expect my figure to be within 2mm. Now, using EP=61mm and a flange distance of 28mm for my Sony A7CR (use 27mm if you like); plus a figure of 7mm for location of optical centre behind dome flange for Nauticam 140 FE dome (use 6mm if you like), an extra 5mm extension is theoretically required plus the N100 to N120 35mm adapter to align the EP with that dome's optical centre. Since there is no 5mm ext available, try none, which may reduce any vignetting. Or try a 40mm adapter if there is one and you can be bothered.... For the Nauticam 180 WA dome (and using a figure of 25mm from old mate now departed for location of optical centre behind that dome's flange), required extension for Sony mirrorless is theoretically 23mm (plus the 35mm adapter). These figures are starting points only, and do not take account of any vignetting (not tested yet).

I just re-measured my Nauticam A7CR rig and it still came out at 28mm. I also measured my Nauticam A7RV and that was 27mm; both using two rulers. I suggest people measure their own rigs... to see if there's any variation. I noticed the tray position is not so precise, so could account for maybe 1mm. Regardless, to make best use of these flange measurements, we will need EP measurements for various lenses (distance from aperture location as viewed from the front, to lens flange); and distance of optical centre behind dome port flange. If you accept that the radius of the Nauticam 140 dome is 70mm, that distance is 7mm (or if you agree with old mate now departed), it's 69mm radius making the variation 6mm. I'll volunteer an estimate of the EP for Sony 20-70 at 77mm, at 20mm (decreasing towards tele end). I wish someone would estimate the EP for their Laowa 10! It's not hard to do! Within a couple of mm will be fine for now. I have EPs for various E mount APS-C lenses, but not much interest in those.

It was a "dirty" measurement, made only for the purpose of calculating required extensions for various off-chart applications, so maybe within 1-2mm which is fine for that purpose. Regarding possible diff measurements for Nauticam / Sony rigs, note that they list 3 diff port charts for Sony N100 ports. Go figure! I have been using the A7RV etc chart and ignoring the others, because it's the most comprehensive. Regarding Chris' comment about Nauticam gear meshing, note that although the gears themselves have only a very small tolerance for misalignment (max approx 1mm) there is a bit of variation possible depending on where you mount the gear on the lens.

I did a quick measurement on my Nauticam A7CR rig when I bought it and came up with 28mm. I think our erstwhile and now departed friend arrived at the same figure for whatever Sony he was using. FYI any A6xxx users following this, the same measurement for my Nauticam A6400 rig was 13mm. Has anyone asked Nauticam to reveal their port / ext recommendations? They should have tested the Laowa 10 by now.

I have a 25mm N100-N120 adapter. 20mm ext might work with that, if 10 ext + 35.5 is a pia??? Still waiting, waiting on my 10 Laowa.

PS: also have not seen a measurement for EP from lens flange for the Laowa 10. I have one on order but goodness knows when it will turn up. Any chance of a quick estimate for that too (method estimating apparent position of diaphragm is fine if you are reasonably careful)?

Thanks for the tests. But what's your measurement for sensor to housing port flange for your Canon R5C (so we can estimate performance for other brands)?

That's an interesting accessory - thanks for bringing it to our attention. Pricey though, like all Nauticam accessories. A question: does the housing hold the vacuum when you remove the bulkhead cap to charge / download the camera? If not, a virtually cost free alternative could be to coil up within the housing a short USB cable already attached to the camera, and whip the back off to download etc (still no need to remove camera and lens).

Price drops: Nauticam adapter now AUD $400. Kenko 1.4 now AUD $130. Offers considered.

Price drop on housing bundle: now AUD $2300. A6400 body, Sony 70-350 and Sigma 18-50 are now sold (Gumtree). Offers considered on all items.

Housing c/w body cap, case, tools. Very good condition. NB: one corner of plastic fibre cable mount filed down to allow N85-N120 34.7mm adapter to fit. No effect on housing integrity as it is a 'wet' (removable) block. Also included: 2 Nauticam battery packs with cables, #25624 M14 Vacuum Valve II (fitted) inc. pump and tool; #83213 M67 to bayonet mount converter, inc installation tool. Total new prices (Scubapix Cairns) AUD$3,981. Asking AUD $2,500. Also for sale (not worth posting details here, so message me if you want anything): A6400 body VGC low shutter count Sony E 18-135 Sony E 16-55 G Sony E 70-350 G Sony E PZ 10-20 G Sony E 30 Macro Sony FE 100-400 G Master Sigma 18-50 DC DN for Sony E All the above in excellent to near mint with original boxes, paperwork caps etc. All will be advertised on Gumtree and some on eBay.

When I uploaded the photos, the system deleted all my text... Trying again: For sale: Nauticam N85-N120 50mm adapter very good condition AUD $420 Kenko N-AF 1.4X Teleplus Pro 300 DGX teleconverter for Nikon AF DSLR, very good condition AUD $ 150 Thanks to all who manage to view this ad! (Why can't we delete a stuff-up??????????)

Phil, thanks for your help, especially regarding the 20-70 and flat port.

I have been pondering this question for some time, and was wondering about shooting the 20-70 behind a flat port, IF I could get say, 35-70 happening. Can't tell without getting my hands on one. I do have the now-discontinued Nauticam Compact Port system which has a larger port window compared to their macro ports, which may help. If I do buy the 20-70, it will only be because I want to shoot it on land as well. Couldn't justify it for purely UW use. I also considered that Tamron 35 1:2, but all the reviews say while it has decent IQ, its AF is poor, which is a deal breaker for me for fish photos. Amazingly, despite a huge number of 35mm options, none focus decently close (except for the Tamron). For now my go to lens is the 40mm Zeiss CF f2.0. Its max magnification is just under 1:3, or to be more precise, a subject approx 112mm long fills the frame horizontally at minimum focus. If you include some background for context, then the minimum practical subject size at minimum focus is say half that (55mm), or a bit less if you crop. Working distance is satisfactory for small gobies.

I think there is a simpler answer to the excellent question than others have suggested. But I don't expect many people to share my point of view... because it's going to hurt! Some assumptions: first, I believe you are the best person to judge your work IF you are honest with yourself AND you benchmark your work against the best you can find. Second, your benchmarking includes against non-underwater photographers. I am a huge fan of Henri Cartier-Bresson because of the way he captures 'decisive moments' ; and lately, William Eggleston, because he can turn something very ordinary into something truly memorable. Or check out the work of any truly great street photographers. Third, I am not referring to technically proficient photos taken for other reasons, such as fish IDs. We can all achieve technical proficiency (and 'acclaim' from others), if we put enough money and time into our underwater photography. So, with the above in mind, how to judge your best work (or anyone's really): To be 'great', a photo has to generate an emotional connection with the viewer. Can be any emotion or even a WTF, but the point is you can't ignore that image; it forces you to engage / ask a question. Go to a gallery or exhibition and really focus on what (if anything) really grabs you, forcing you to linger, or come back for yet another look. Imagine you print and frame a photo that you think is great, and hang it in your hallway. The question then becomes - how often do you look at it? Every time you pass it? Or can you walk past it and ignore it? Or maybe you have another amazing photo as your PC desktop. Do you ignore it, or do you catch yourself having a peek whenever it shows? Or maybe you have whittled down your files to the best ones as suggested by others above. How often do you look at those, and how do you feel about them, especially after a year or three? Do you still get the wow factor, each time you view them? Or are they more 'ho-hum' after a while? The answers to these questions will be self-evident, but unless you are some kind of photographer prodigy, the result will be that very few of your photos meet this tough criterion! The rest may well be brilliant for other purposes, such as illustrating books, articles, scientific papers or impressing others; but are frankly... quite dull!

I've kept my APS-C Zeiss Touit 50 after changing from A6400 to A7CR because it's such a great lens, and AF is fast enough with the latest Sony bodies. I use it in crop mode. I doubt I would ever sell it, as it also has other advantages over the Sony 50, inc internal focus (no extending) and more compact design. Re Nauticam ports for this lens on the A7CR, I use N100 to N85 20mm adapter plus original N85 45 macro port. Super compact. NB: sensor to port flange increased by 15mm for A7CR housing vs A6400 housing. Total extension is therefore 65 (plus the extra 15); vs 75 as per Nauticam port chart for Sony N85 system (45 macro plus 30mm ext). As I've posted before, with crop turned off, it vignettes quite a bit at the ends of the frame. However, if you then change from 3:2 to 4:3 aspect, only small corners are vignetted. I might post some examples when I have time.

Nikkor 16mm has sold - on eBay. Offers considered on the 4 gears and bayonet converter.

Industrial parts suppliers (in Australia anyway) stock a huge range of O rings. Suggest take your old ones in to a bricks and mortar store and have them measured. Industrial replacements may not be made of the same material though. Be sure to test the housing (vacuum or in-water) with the new O rings before risking a camera.

Well if you already own it, no harm in trying. I wouldn't rush out to buy one specially though. I tried a manual fisheye and a Laowa Zero D 9mm (both for APS-C) and found them very difficult to focus accurately. Focus peaking didn't help. Pre-setting the focus is also not great, although it's doable if you know in advance what sort of distances your subjects will be at. First the entire focus range is compressed from infinity to MFD into (say) 25-50cm, depending on the lens. Second (with Nauticam anyway) I couldn't read the focus scale on the lens underwater, and was forced to "convert" land distances to UW distances by making a scale to fix to the housing. All very unsatisfactory.

I have just finished reading your review in UWP. It's a nice summary of your findings within this thread. I second your comments about tolerance for soft corners... but that's a whole other topic. I have marked up July in my calendar to keep it free to devour 121's 'structured testing' of the Laowa lens when it emerges. As the self-appointed guardian of paramount optical quality, he will have much to teach the rest of us plebs. Long may his corners emulate his centres...

There is an interesting article on this very topic, with underwater examples, in the current UWP.

As I already said, lens focuses from about 50mm in front of dome, which is fine for CFWA. Infinity focus no probs too. Enough of your nonsense.

45 EP - 28 (lens flange to housing flange distance) does not give 5-6 ! Check your maths... 45-28=17 required extension. But I am using 25mm adapter (not 35.5) with A7CR which naturally provides 25mm extension.. 25-17 = 8mm excess extension.. But the height of 140 port is 63-64mm with radius of 70mm, so difference is 6-7 which is a required extension. So 8 minus 6-7 gives a mis-alignment of approx 1-2mm excess extension. Pretty darn good. If as you say in the other post, radius is 69mm, alignment is close to perfect! Or in practical terms, no extension required, for this lens, this port and 25mm adapter.....

My measurements are accurate within + or - 2mm. I need the radius to check if a lens with a particular MFD will work with the port, and where the optical centre lies. I don't trust published port diameters. 69 vs 70 makes no difference for this purpose. 63mm (+ or - 2) is top of glass to port flange, a distance necessary to work out required extensions for a particular lens. Would be great if manufacturers made this info available for those of us who want to go 'off piste' from published port charts.