Architeuthis

I suppose the problem in this photo may be slightly out of focus. Also diffraction at f/20 will contribute to softness... When your photo is not sharp with 24 Mpixel, it will not become sharper with 60 Mpixel. Switching to A7R5 will not better these images... Wolfgang

This is very sad news, thanks for posting ...😢 Is there a scientific study available on the Raja Ampat bleaching event, especially on the role of sewage in coral bleaching and dying? I returned yesterday (March 22nd, 2025) from diving vacations in the Red Sea (Egypt/El Quesier area). Last stay there was in September 2023 and the coral still looked reasonably intact and little influenced by record heat and bleaching at this last stay, suggesting that Red Sea coral is pretty heat resistent... => The diving this time was sobering and really heart breaking (I dive in the Red Sea since the 80ies and have to face now this diving paradise vanishing): substantial amounts of hard coral (but also fire corals (which are not corals but hydrozoans)) dead and covered with algae (similar as in the video above by Dr. Dustan). Fish population greatly decreased, indicating that the entire ecosystem is out of joint ... 😞 Wolfgang

Hi Michi, Did the settings solve the problem with the A1? Unfortunately I do not have a file with the EM1II settings here at hand (we are currently for diving in Egypt, in case such a file still exists it may be still at home on our NAS server)... Here is s link for general settings for EM1II for UW use, maybe you can find something useful there: https://www.uwphotographyguide.com/olympus-omd-em1-markii-best-underwater-settings#Initial Settings In case you want know a specific EM1II setting, I can have a look at my wifes camera in the later afternoon, when we are done with diving. She is currently using the EM1II with Nauticam trigger with Z330s. The cameras are now ready in the housings and we go diving soon... Wolfgang

I did not try with the N85 version of the Zen DP100, since we have the N120 version, without extension, here. Possible that the N85 extension rings are to narrow for the zoomgear, as you figure out... I have a 30mm N85 to N120 extension ring here (without locks) that has been made by my local dealer (https://www.unterwasserkamera.at/shop/catalog/en/). Lisi does not use it any more, as the Nauticam 34.7mm N85/N120 extension works very well instead of the custom made 30mm extension (I have put it into the classified section here, in case someone is interested... When I look into the Nauticam catalogue, I cannot find the N85/N120 34.7mm extension any more. It seems they have discontinued it, this is a pitty if true...☹️ The dealer linked above should be able to produce also N85 extensions (without lock) at any length upon request and the costs are bearable (but I myself would go with the N120 version of the Zen DP100 and is it just to remain compatible with a later N120 system. Also the reselling value is higher, I think)... I also have tested the N120/DP100 with the Canon 8-15mm. It works fine, I could not find a difference in IQ compared to the 140mm domeport, but one has to remove the sunshade from the lens in order to fit into the smaller port (maybe the assembly is more prone to flare then)...

I am not sure that this is really "very expensive", but I did not count all the positions together for comparison. I, personally, think this is the optimum WA setup for MFT... The think the different solutions would be: #1.: 8mm MFT fisheye with small domeport plus another, additional, solution (e.g. rectilinear WA (8-25mm) with big domeport & extensions (e.g. Zen DP170), maybe better WWL-1B plus flatport/standardzoom). => A lot to carry around for travelling, also the second (WA) rig UW is big&heavy... => One has to decide before the dive whether to go "All In" (180° diagonal, 😃) or less wide... #2.: Canon 8-15mm, 1x Metabones adapter with 140mm domeport (via N85/N120 34.7mm adapter plus 30mm N120 extension) => Probably everything many people, including me, ever want for UW WA #3.: Tokina 10-17mm, 0.71x Metabones speedbooster, 100mm Zen domeport (via N85/N120 34.7mm adapter plus 20mm N120 extension) => extremely smart & small setup UW (also for travelling), I cannot see a difference in IQ compared to Canon 8-15mm (my wife loves this setup and uses it all most on every dive for WA) Wolfgang

The flash is sold now...

I cannot say about the Artisan 4mm fisheye from my own experience, but the lens looks short and it has a 225° circular angle of view. Probably it will be difficult to place in a housing and put a dompeort in front without vignetting. I assume it is manual focus what means you will need a focus gear for focusing on the virtual image of the dome (setting focus just close to infinity will not be enough)... I have used the Sigma 4.5mm circular fisheye (https://www.sigma-global.com/en/lenses/45_28/) with Canon EF mount via Metabones 1x adapter on Olys EM5II and EM1II. Since the lens has substantial length, there were no problems with placing in it Nauticam housing and using domeports with appropriate extensions. It also is a lens with AF. Optical quality is, more or less, what you expect from such a lens, it is reasonably o.k., but not as good e.g. as Canon 8-15mm @8mm on FF (Sony A7R5)... Wolfgang

When I switched from Z330 (1st generation with white dome WA diffusers) to Backscatter HF-1 (with 4500K flat diffusers), I clearly noticed that the HF-1s are less prone to "flare" at the edges of the images. I am not sure, but probably the reason is that the HF-1 standard diffusers may provide a less wide beam angle... The physical factors (see below) are different between between different models. In my case every new strobe required learning during the first dives, also how to avoid "flare" in very wide WA, but there was always an improvement at the end (YS-D2 => Z330 => HF-1 in my case)... In general the factors influencing the "flare" are: flash beam angle, beam softness, in/outward aiming of the strobe, distance how far the strobes are pulled back behind handles, angle of view of the lens (most important factor: almost impossible to get "flare" with 17mm rectilinear behind 170mm domeport, even difficult to produce with WACP-C/@28mm, but very easy to get with fisheye 180° diagonal or circular), light shade on the dome (yes/no) and (maybe; I personally do not have experience with circular flash tubes) shape of the flash tube (circular/linear). ISO, aperture and flash power have same effect on "flare" as on the rest of the flash lightening - therefore I would not use them to control "flare" (maybe "flare" disappers in the EVF when parameters are adjusted, but upon postprocessing the "flare" will reappear without mercy - better eliminate "flare" by other means)... Wolfgang

Definitely there is a reason. You want to take off the cap when you are UW and start to make photos. At the end of the dive, before you start going out, you mount the cap again to protect the precious wetlens (before you hand your rig to stuff on a zodiak). Domeports are mostly vulnerable in the short period when the rig is lying unprotected in crowded places while people enter/leave the water... In my case it is WACP-C, but the cap is very similar, if not identical. Similar to the others here, I have drilled a hole in the cap to mount a boltsnap via an accessory cord (redundantly secured with a cable ties). I mount the cap to a D-ring on my jacket and this is perfectly o.k. ... Wolfgang

I think the problem is not the optical quality of the Sony 2x TC, but the optical quality of the lens that is used together with the TC. The resolution/performance of a lens without TC may be o.k., but an excellent 2x TC amplifies the weaknesses of a lens without mercy, if such weakness exists... See e.g. here these test photos of both the Sony 70-200mm lenses (GM f/2.8 II and G f/4 II). At 200mm/f4 both lenses perform nice, but at 400m/f8 when the Sony 2xTC is attached, the IQ of the G f/4 II lens becomes really low, while the GM f/2.8 II is still acceptable: https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1577&Camera=1538&Sample=0&FLI=5&API=4&LensComp=1662&CameraComp=1538&SampleComp=0&FLIComp=5&APIComp=2 It seems to me that the Canon 8-15mm is a high quality lens. IQ becomes a little soft together with the Sony 2x TC. Softness is, however, worse when I use the Canon 8-15mm together with the Kenko 1.4x TC (the non "HD" version). Also IQ of Canon 8-15mm/Sony 2xTC is comparable to WACP-C/28-60mm at the 60mm end (the 28mm end is sharper)... Wolfgang

Hi Martin, I have just bought the the Sony 1.4x TC for use with Canon 8-15mm in Nauticam housing and (mostly) 140mm dome (A7R5; have been using the Sony 2xTC&Canon 8-15mm now for two diving holidays (Croatia and Tansania) and it worked also nice (Image sharpness in center, more or less, comparable to WACP-C with Sony 28-60mm (both are, however, not "excellent"), corners similar. I do expect, however, better IQ with Sony 1.4x TC, therefore the acquisition of 1.4x)... The length of Sony 1.4x TC is 17mm, therefore an additional extension of 20mm should be perfect (in addition to the 30mm extension recommended by Nauticam; remember that Dreifish, based on the chessboard test, recommends 35mm instead of the "official" 30mm as theoretical optimum for the pure lens, w/o TC). The 3mm more, when the 20mm extension is used with the 1.4x TC, is fully in line with Dreifish's recommendation (alternatively one could use a 25mm (instead of 30mm)&20mm extension and this is probably also o.k.; I will be able to test the different extensions in the Red Sea only in March and can report afterwards (takeoff in 2_1/2 weeks 😋); I will also report my personal opinion, whether the switch to 1.4x TC indeed brings additional IQ and is worth (2xTC offers much better zoom range)... I have the Metabones V adapter and this works perfect with the Sony 1.4x TC and Canon 8-15mm. In case you have already the Sigma MC11 adapter you can test it out easily by yourself. In case you do not have an adapter yet, why not the Metabones V (at least theoretically, it should support AF modes a little better)? Wolfgang

I carry strobes with me in cabin lugagge, but Nauticam housing (in the travel bag) is checked-in in hardshell suitcase... Cabin lugagge, in my case, consists of Fotorucksack (approx. 10kg) plus Fotobag (approx. 4 kg). Just camera, lenses, flashes, Li+-batteries, dive computers, compass and travel documents. In addition, I wear a big "outdoor vest" with many pockets, just in case I would have to remove items from the Fotorucksack (never required, so far)...

The pulses, I guess, refer to electricity. The gas glowing in the flashtube will not stop emitting light inbetween pulses, maybe light intensity jitters a little at these extremely high frequency (remember the (rather slow) exponential decay of light intensity after a single pulse, shown sometimes here by our flash engineeres, who have the tools to record light intensity in time at high resolution))? In the end, a particle producing backscatter is illuminated by a flash pulse that lasts for 1/320s in HSS mode in your example. This compares to illumination by a flash pulse, lasting a little shorter than maximum shutter sync speed (depending on flash type and light strength selected), in normal flash mode. So the end result is expected to be pretty much the same...

I have just finished and printed an extension ring for the Nauticam zoomgear for the Canon 8-15mm fisheye lens with Sony 1.4xTC to be used via adapter (Metabones V in my case) on Sony cameras (A7R5)... After printing, I cut threads for three grub screws into the ring in order to fix it firmly to the Nauticam aluminium gear. Canon815_2xSony.stl

I find it difficult to find in the Internet a description how, exactly, HSS is working. Therefore my argumentation may have faults, but I can see none of them so far... According to what I was able to find out about HSS just now, the pulse frequency in HSS is mode is very high, up to 100 kHz, what makes the individual pulses merge and causing the flash to provide a single pulse, with, more or less, constant (but a little fluctuating) intensity that lasts for the duration of the entire exposure (=much longer than the shutter speed adjusted). => This would mean that in HSS mode the individual pixels are exposed to flashlight for exactly the time that is adjusted via the shutter speed. i.e. a single pulse ...