Chris Ross

Without the port charts coming out and assuming they include the diagonal coverage at short and long ends it's basically guess work. You can do some calculations based upon assumptions to work out what the field of view might be. SO if you assume 180° diagonal and an Equi-solid projection you get this with a comparison to a WACP - from a post of the FCP thread over on wetpixel: If you don't get 180° diagonal with the FCP then the fields will be proportionally narrower all round and if the projection is different (the formula to work out how field changes with focal length ) then the field at the long end will change. This is as good as you will get with current information, hopefully the port charts will show the zoom range when they eventually come out. I wouldn't expect the fields to be hugely different from this. I would though say that the range will be larger than the Tokina 10-17, which is a 1.7x zoom, the 28-60 is a 2.1x zoom. If the wide end is indeed fixed then a higher zoom ratio will give you more reach on max zoom. Likewise the 28-70 would be 2.5x and the Nikon 24-50 would be a 1.8x (28-50 being available.) The problem with the Nikon 28-70 is lack of a solution for a screw drive lens on Nikon Z.

The EMWL is quite heavy, the additional components for Sony weigh 1.8 kg dry, 1.1 kg wet and much of that weight is cantilevered on the flat port with a large twisting moment that needs to resisted. It doesn't strike me as an option for someone who doesn't want to travel with a 230mm dome. My first thoughts for a more manageable setup would be a 140mm dome with a fisheye, but probably not ideal for sharks and mantas but adding a 1.4x times might go close to having enough reach for sharks etc. typical setup have two large floats on long arms for the strobes to hold the nose up. I would think anything with decent current and/or requiring quick maneuvering would prove trying. I'm thinking negative entries in current prone sites might be a significant challenge? The person best qualified to answer is likely to be @Alex_Mustard so hopefully he might chime in.

Hi Colby, welcome aboard and question away!

Which DP-170? You say it's an N85 there are two of them, one with 60mm extension and the other with 30mm IIRC, sounds like you have the one with 30mm extension. Phil Guessed at the right extension being 30mm. The N85-N100 is 20mm long so you would be looking at 50mm total extension with the DP-170 port with 30mm extension built in and the adapter. If it doesn't vignette with that you should be able to use it - albeit living with a possible non -optimal position in the port. If you knew the flange back length of the Sony A7x housing (distance from lens flange to housing surface ) you could do some calculations. An easier way might be to do some port chart comparisons: First up the Nauticam 180 and Zen DP 170 both use the same extension for most lenses in their port charts. Next Marelux include the 20mm f1.8 in their port charts where it uses 50mm extension with their 180mm dome Marelux also list the Sony 16-35f4 Zeiss which requires 40mm extension for same port. Similarly for the 16-35 f4G lens Marelux is 70mm while Nauticam is 80mm extension. The Nauticam system requires 10mm more extension the Marelux system for these lenses. SO for Nauticam the 20mm f1.8 requires 50mm + 10mm = 60mm extension. With the DP-170 N85 port you have 50mm extension. By this comparison it should work OK without vignetting with just the adapter. The port charts suggest you need 10mm more extension, so you could try it with just the adapter and decide if you want to also get the a 10mm extension as well.

A question Phil, you are comparing the light quality with the bare flash, If they both have diffusers like you would if using the 4600K diffusers for blue water wide angle work, is there much difference in light quality?

The best possible solution for snoot use with a Z-330 or Z-240 is probably to use a different strobe I think unless someone develops a snoot with a prism to centre the beam in the snoot.😂 A lot of people add a Backsactter mini flash to their setup rather than try and deal with snooting a strobe with an off centre pilot light. But seriously I don't use the lights on my INONs, they can't illuminate your subject for you as the have a narrow beam, the first rule of UW strobe shooting after all is don't point your strobe at the subject (unless snooting of course).

Thanks Phil, there is indeed some variation, but I think that is a seperate problem if you get into all the possible variations of different manufacturers ports you come up with too large a comparison. On a relative basis (not an absolute basis) you still should be able to compare coverage horizontal differences between a rectilinear and the wet optics. The calculations are mainly to calculate the horizontal coverage from the diagonal. The diagonal coverage can be misleading as the the corners stretch so much due to barrel distortion in fisheye lenses and wet optics. Just to clarify the photos are 28-60 at 28mm for first two and Tamron 28-75 at 28mm for the last and they are all behind a WACP or WWL optic at varying extensions taken from a fixed location in the pool?

Quite likely it will - the Sony 90mm had a reputation for slow focus until cameras like the A1 came out, it seems that the body makes all the difference for the 90mm. Though I don't know that struggles is the right word, the article seems to imply the 50mm was slow but accurate. Here is a thread from WP a while back on the subject: https://wetpixel.com/forums/index.php?/topic/70686-nauticam-a6400-macro-options/&tab=comments#comment-448035 Note that a macro wet lens is not really an option for the 50mm as min focus is so close to the port with just the lens. This I think is the Phil Rudin post you mentioned: https://wetpixel.com/forums/index.php?/topic/67134-sony-a6400-for-macro-and-super-macro/&tab=comments#comment-424189

This article provides some comparison between the 90mm and Sony 50mm macro: https://www.divephotoguide.com/underwater-photography-special-features/article/blackwater-photography-anilao-philippines-sony-alpha-1-a1/

No problem, you would certainly want a drysuit for the cuttlefish aggregation, 12°C water and cool breezes running with low air temperatures. Wet suit is fine for daytime diving up till April- May for most divers. Sydney you can usually get away diving wet till around June and many dive wet year round. It's the boat dives where drysuits come into their own in winter.

I find it is usually best to ship via the mail, courier companies might be a little faster but if customs clearance is required they sting you pretty hard for that, while I can do that myself for mail items. The rule is if the cost is less than $1000 AU the parcel is delivered without GST (10%) being collected and being a gift makes no difference.

The reds are not coming through on this one, so here's a link to the image on my google drive Link to image on Google drive

A Sydney Pygmy Pipe Horse, another specialty of Sydney dive sites, they are tiny, cryptic and near impossible to find, I have had people point them out to me and I couldn't see it for ages. This bright red one does stand out a bit more than most, they usually look like scraps of weed slightly out of sync with the surge. Nicely spotted by my dive buddies on fist dive for 2024 today Taken with OM-1 + 60mm macro, Nauticam housing, INON Z-240 strobes. Happy New Year everyone 😄!!

Good to see another Aussie onboard, welcome!

Really nice, when did you get to Adelaide? I'm planning on driving across maybe April for a few dives.

Hi Massimo, I'm interested however I already have a Metabones adapter. Are you interested in Selling all the other parts - shipped to Australia?

No they are the same file so should be identical, I think the tweaks done fixed the issue of the colour changing. I think what happens is the forum software uploads the file and creates a thumbnail to display in column and also creates a somewhat compressed version to store, which is where you can run into trouble depending upon settings.

and by the way Giant cuttlefish season in Whyalla is June- August for the aggregation. I probably wouldn't travel all the way to Whyalla unless you there for aggregation. You will likely see Giant cuttlefish at the other sites like Rapid Bay I saw one there and also in Sydney. This Giant cuttlefish was at Rapid Bay jetty.

Australian weather is not really seasonal, rather there are frontal systems alternating with highs moving across the country from west to East and the wind changes with these systems coming through. Having said that the centre of the high pressure systems moves north-south in winter/summer which changes the average wind direction, so the East coast gets more westerly winds in winter for example. So basically it is a case of being in town long enough for the wind to move around to where you want it, with seasonal wind directions favouring one site vs the other. You can find a wind rose (pdf file each month) in this table for Edithburgh: http://www.bom.gov.au/climate/averages/tables/cw_022046.shtml and Noarlunga near Rapid Bay: http://www.bom.gov.au/climate/averages/tables/cw_023885.shtml Here are location guides: https://indopacificimages.com/australia/diving-edithburgh-jetty/ https://indopacificimages.com/australia/diving-rapid-bay/ Edithburgh is hazardous in south - south east winds, while Rapid Bay is sheltered from those winds while Rapid Bay won't go well in North winds, but on average is more sheltered. You might want to contact one of the local dive shops, presumably you would want to rent tanks and weights and not travel with them, also in Edithburgh which is about 3-4 hours drive from Adelaide there is no dive shop so you would need to bring tanks from Adelaide. You can however get air fills at the service station in town. I used Dive Adelaide and they were very helpful. Final consideration in water temperature, it's dry suit diving (11-13C) in winter and into spring while it can get to 22° in summer through to about April. Do you want to travel with a dry suit or dive in a wetsuit?. It can get stinking hot in summer so a sauna inside your suit till you get wet. All things considered I would go in April weather tends to be calmer then and avoid being there in School holidays so you can be a bit flexible with accomodation, you would probably want to over night in Edithburgh when you travel out there. Then pick your days at each site according to the weather, you can generally get a good idea 4 days out from the BOM website and swell forecasts: https://swell.willyweather.com.au/sa/yorke-peninsula/edithburgh.html Probably want to avoid long period swells . While you are in the country you might fly in and out of Sydney - go diving there for weedy sea dragons. Again it it's a matter of timing for swells and wind.

Thanks everyone, It's pleasing this has come along so well and that so many people have come across. I would say to contributors, the best way you can help move the forum along is word of mouth, more people and more points of view and contributions will help the site along. So if you happen to be talking to people about UW photography point them in this direction!

This is not surprising as if you look at tests you'd find the Oly 12-40 would be crisper in the centre than the 28-60 kit lens. Also a 24mm equivalent lens is not that much of a test of dome port optics. The WWL is not going to make the centre sharper, but provides better edges at wider f-stops than you could get in a dome. For shooting sharks the edge sharpness is less important. I use the 12-40 in a Zen 170mm dome and really like it for temperate water diving, what I really wish for would be a 10-40mm lens with same close focus performance.

The calculations are based upon the Nauticam port chart and the diagonal field of view they list. All the calculations do is estimate the horizontal and vertical field of view based upon the reported diagonal field of view. So on this basis the calculations are only as good as the fields provided in the port charts. The calculations are done for a number of projections as the horizontal and vertical fields are different in those projections at the same diagonal field and we don't what projection the Wet lenses are. This happens because the corners are stretched more or less in the various types of projections. The short version is if the calculations are incorrect, so are the port charts, but they are only applicable to the port/extension combination used in the port charts. A complication is that some domes are not full hemispheres. As Massimo points out the maximum field of view of the 180mm dome based upon geometry is that of a 16mm lens, however if you look in the port charts this dome is recommended for the Olympus 7-14mm, a 14mm full frame equivalent lens. The only way you do this and not vignette is to place the entrance pupil forward of the optimal position. In fact the issue of correct extensions is a bit of a red herring herring for the purposes here. What we are trying to do is compare reach of different combinations. Reach for example is about whether or not you can fill the frame with a shark that doesn't let you get closer than 3m for example. You don't need calculations done to 3 decimal places to check this, what you need is consistent calculations and in the case of not knowing the projection a way of cross checking. We can't compare every combination of extension and port size all we can do reasonably is compare recommended dome/wet lens/extension. Even if you are out a bit in extension it's not going to really change the answer as we are doing a relative comparison and extension change that still has reasonable image quality is not going change the field enough for you to decide differently which lens has enough reach for you. As Alex Mustard has pointed out before, this is only part of the equation - a fisheye projection provides a different impact to the image with close focus on the central subject causing it pop out and causing sharks to look fatter as examples. However if the shark is too small in the frame that's all moot, when you need reach you really need it and this discussion is about getting that reach while minimizing the loss of field of view if you also want to take some wide shots on the same dive.

Prevention is better than cure. On the boat keep the port wet with a neoprene cover till you can rinse it. When you get the housing back home or somewhere you can soak it give it a good soak then blow all the water off and dry off and polish with a micro fibre cloth . Basially avoid water evaorating from the surface. The water marks are not usually a deposit but tend to be bonded to or etched into the surface which i why they respond to polishing.

This table shows calculated values for fields of view diagonal/vertical/horizontal. If you want to compare coverage or reach I would suggest comparing horizontal fields is probably best . Not the same picture of course but is probably best for comparing how the lenses would go for example shooting a shark. The top 4 lines are rectilinear lenses. Then follows 5 ways of calculating the WWL coverage with a 28-60 lens. Stereographic projection seems closest to right as using a constant focal length multiplier to get the fisheye equivalent focal length it comes closest to predicting the full zoom diagonal field from the widest field multiplier. The equivalent focal length I'm using is adjusted to get the formulas to match Nauticam's figures for the WWL diagonal field from their port charts. Equisolid, equidistant and stereographic projections are reasonably close together predicting the horizontal field while Orthoganal and rectilinear are much further apart. T To demonstrate how far out the rectilinear formula is, I used the 0.36x factor for wide and full zoom it while it predicts the wide zoom it is 30° out on full zoom. I think the Sterographic projection is probably reasonable to predict the reach of the WWL to compare with the rectilinear lenses. Various caveats apply such as field being reduced at min focus distance etc, but it should be good enough to compare the reach of the various lenses.

Don't know what it will be like on the Z8, but on my OM1 which has one of the newer larger EVFs the edges are fuzzy with the original 45° viewfinder, which includes some status info. The newer ones are preferred with the new viewfinders. Mine is a carryover from the old housing, but if I were to buy new I'd spend the extra to get the best view. The 0.8:1 is designed with a wider view more mirrorless cameras specifically to include the information around the edge of the frame. This video might be helpful, there's a lot of bakground and it gets into the meat of it about 8 min in. And starts talking about the 0.8:1 10 min in. Alex says he prefers the 0.8:1 model even for the SLRs.