Chris Ross

I didn't see that in the linked page and I searched the article, is it in the video or somewhere like that? I think UW photographers are the only people on the planet who might be interested in adding a converter? The issue is that the Canon RF 1.4x has a very long nose. On the 190deg field maybe the solution is to position the lens at the 180 deg point in the lens and the blue ring will be vignetted out? On the filter holder, this is similar to what is used on the big tele lenses. If it gets in the way of the zoom ring you might be able to remove it and put some tape over the hole. Also the position of the zoom gear in the housing will influence whether it's a problem, the Nauticam housings for example position the camera back in the housing so there is room for an RF-EF adapter, which means the gear will be forward of where the filter holder is. All of this will be confirmed or otherwise no doubt once the housing manufacturers have tried it out.

As I understand things Coca Cola is not a routine cleanup medium, I have seen people suggest using it after a Li-ion battery has been flooded and the battery compartment is full of sea water mixed with battery innards, The blend of sea water and the internal components of a Li-ion is going to be far worse than Coca Cola. The active ingredient of coke is phosphoric acid, that's why it makes tarnished coins look like new. I don't think I would put it a battery compartment unless I had a flood. You do need to consider what the strobe is made from - plastic strobes could be harmed by hydrocarbon solvents used in some contact cleaners, likewise just pouring isopropyl alcohol in is not advisable as it may react with some plastics. There was a post some years back with advice from Reef photo about what could happen to a flooded INON strobe, they said that plastic used in INONs was strong but not chemically resistant. Isopropyl should only be applied to contacts with a Q tip not poured in. IMO Coca cola would do less damage than alcohol - plastic is generally inherently resistant to acids especially relatively mild ones like phosphoric.

I think the value of something that old is just not there, even one generation old gear sells for very little. You might get lucky and get some $$ or not. I see a couple of options, Get it serviced and keep using it. Find a low actuation body as a backup. Retire it and get another system you could see what was available second hand and if you get a complete system and don't try to keep using your lenses it's probably easier to find something you like. Retire it and buy a new housing and body and try to salvage your lenses and ports. Adapting your macro lens to mirrorless may not be so great in performance though??

In general, no, flat ports are used with macro lenses for a reason. Yes the corners will be slightly better, but you can't add on a diopter if you wanted to and the large size of the dome makes it more difficult to work in close. For some specialised uses a dome has some advantages, but it seems not all macros lenses work well in domes due to the location of the entrance pupil either moving or being right at the back end of the lens.

😃As much fun as it is to measure and research new stuff, not much point to it unless we go diving!

@Alex_Mustard had some posts on using a dome port with macro lenses, he typically used one of those small section domes for this, here's one article on this: Inside ScubaShooting Macro With A Curved PortExplore the benefits of curved macro ports for underwater photography, including improved image sharpness and a wider angle of view.I remember some posts on Wetpixel possibly, but can't find them right now.

I expect that using a fisheye with the RF 1.4x and 2x won't be an option as they have a protruding front element and the also a special bayonet that will only mate with lenses specifically designed for the converters. It needs the right bayonet and enough space at the back to accommodate the nose on the front of the converter. If I recall the RF 100mm macro won't accept them so it seems unlikely a fisheye will, UW photographers are unique in making use of a fisheye zoom and converters. The Kenko converters are different in that they are designed to work with any lens as opposed to only the ones the manufacturer thinks could use one. I don't believe Kenko make an RF 1.4x or 2.0x as Canon doesn't allow Full frame third party optics to be licensed though. Be interesting to see if the lens does appear though.

You will note in an example in the video, the lens used a 17mm extension added to if I recall correctly a 30mm ring. However the video notes that the combination vignetted, so the suggestion was to just remove the 17mm ring and just use the 30mm. This gives you an idea of what you can get away with. IMO an ultra wide rectilinear lens (14mm FF equivalent or less) will be more sensitive than a fisheye lens. I think it likely also depends on the lens in question. A marginal performer might show more issues if the spacing is less than optimal. I think the right answer is get as close as you can within the limitations of your housing system. Some systems have 10mm increments others the extensions go up by 5mm.

I'm using a bayonet holder for my MFO3, I'm on m43 so the magnification of the 60mm macro lens is sufficient and I don't use a diopter. So only taking the MFO3 on and off and not needing to park a diopter. Swapping them is fairly easy, the MFO3 is a heavy lump above water, but doesn't give me problems below water. I also used cargo shorts when diving in Lembeh, I only needed to fall off the boat so no issues with them falling down, not an option shore diving in Sydney where I use the bayonet. The bayonet holder is mounted on a strobe arm, when I'm entering/exiting the water I have the neoprene bag it is supplied with covering the lens. Getting washed into the rocks exiting is a common enough occurrence that some protection is needed. Once UW I remove and clip off the bag.

I really think the fundamental problem is the response curve of the camera. That's not a fault rather that is how they are designed. The way around I think is to reduce the exposure. Easiest is lowering the ISO if possible, but looks like you at ISO 50 already, so maybe place a grey card on the wall and measure brightness off that or double the strobe's distance from the wall. You might run into problems at the low power end, but within the limitations of equipment you have available seems like this might be the best solution. You would need separate sets of measurements for the high and low powers. Also as I understand it ISO 50 on the Z8 is extended ISO which is achieved by over exposing the image and pulling the exposure down which tends to blow highlights. Maybe for the Z8 base ISO might be a better option?

quite a bit more than reported on Backscatters website, which is good.

Potentially, but the LEDs are only 1000 lumens at max power where they have a 98 minute burn time, spreading that into the 110° beam means you only have 30% of the light falling on the target that a 60° beam would give and that's assuming that the edges of the beam are as bright as the centre which they won't be. The strobes are also likely to be further from the subject than what a focus light could be. I use a 700 lumen light with a 60° beam which works quite well. You don't need to have a very bright focus beam for the AF to work, but I think if it was significantly dimmer it might struggle.

😂, I wouldn't be doing it either!

It depends upon where you are diving and also how you are shooting. For snooting, you aim the target light directly at the subject , so a focus light is probably not required. For macro without a snoot, you probably are not aiming your strobe directly at your subject so the target light can't help unless it has the same beam spread as your strobe. If there are lots of overhangs and caves around, the focus light can help you find subjects particularly if they are a bit cryptic. If I was going to shed a focus light anywhere it would be for wide angle, but again you might want it in caves under overhangs etc. I have a fairly short macro port so I mount the light in the housing hotshoe an a long YS mount, this one: Exposure UnderwaterHotshoe Nauticam YS ConnectionYS conncetion for accessory shoe. To attach for example, a focus/video lamp or a strobe.

As I recall the gamma curves from cameras flatten out in the highlights - it's certainly not linear response, I think that is what may be happening. In which case you could have a separate curve for the top end shot at a smaller aperture, lower ISO or an ND filter or some combination. Those high powers would probably manly be used where you can't get as close perhaps? Ideally you would use a flash meter.

Just to confirm as I read it, the HF-1 full and boost modes are listed in manual with limitations on usage with the thermal protection potentially cutting in too many flashes occur, the manual suggests 35-55 full power flashes before it cuts in. Retra doesn't suggest a number and advises to shoot in intervals and pause occasionally, they recommend 5 shots max on their boost mode. Seems like for practical purposes the maxi is effectively brighter than the HF-1 as full power without boost is as bright as the HF-1 at +2 and +2 seems like it has a limited number of flashes before throttling occurs. Regardless seems they are very close in guide number. It is interesting though that you measured the brightness at full, +1 and +2 as very similar. The manual notes that you should get over 1000 flashes at full and over 375 at +2 indicating the strobe is drawing more power in those modes. I also saw it has automatic throttling of light as thermal protection, so wondering if this has kicked in - though I see that the strobe is also meant to emit a long beep if it kicks in and I'm sure you would have heard it if it did. A further thought, both the maxi and HF-1 are very close in in output as measured by photoshop brightness and seemingly close to saturation and both at some power level step show a sudden drop from 90s to 60s in brightness. I'm wondering if the accuracy of using Photoshop to indicate brightness breaks down a little when approaching saturation?

I have tried this on land with a tent made from white ripstop nylon (for diffusion) It is surprisingly difficult to keep all of the air currents out, basically you have to completely weigh down all of the edges and closeup up the velcro zipper around the camera and/or lens to allow no air currents to get in and keep the subject still. Using a shield that is not sealed doesn't work period. You also have the issue that the shield will appear at least partly as the background if it is fully wrapped around. I think any air that gets in then has to exit somewhere, either that or billowing of the tent sides causes air to flow in and out through any opening. In water the forces are going to be greater so any sort of tent or shield will want to sway in the surge as well. Surge can move you, the diver around so anchoring any sort of shield is going to be difficult as the forces on it are quite high. If the shield/tent is loose fabric or mesh it will move and this movement will move the water on the other side of it. It might dampen it a bit but I don't think it will stop it. Being a wave, the surge will also diffract around the edge of the shield. Even if you could find something of an appropriate size, anchoring it on the reef without damaging things or causing subjects to flee I think would be a bigger issue.

Most operators in Lembeh support photographers quite well, the guides are very good at finding critters and will go off and find the next one while you are shooting . I stayed at Divers Lodge Lembeh recently, the boats all had rinse tanks, no camera room but did have a table in each room with good lighting to work on your camera. They were quite used to working with photograhers. Other locations have dedicated camera rooms and other features. In Raja Ampat, the Sorido Bay resort recently announced the establishment of a Seacam center on site to support photographers.

If I am reading things correctly Killiii's test shows some interesting points. First he tests at 8 FPS on the Apollo III in MTL at 12 = (max power) and it illuminates every frame and drops one stop in power by frame 8. It stabilises with constant brightness when power is reduced to 9 . The important thing to note that full power in MTL mode is about 1/2 the max output of the strobe. So it is one stop down from max power in regular manual mode. The Retra Maxi goes close to the this when set to -4 power- it starts brighter and drops to lower than the the output from the Apollo after a few frames. I'm wondering if the test would be more informative if you set the Retra Maxi at a power to achieve the same light level as the Apollo III at the 9 setting? It should give a few more frames at that setting compared to what was achieved in the test. The test then goes on to compare the Apollo III and Maxi at 6 FPS with a diffuser on the Apollo as it really needs one to get close on light quality. Settings are 12 and -6 respectively and the light output is the same by the light meter reading. To me it seems any comparison should be at a setting where light output is constant and equal. If you want high speed shooting then only getting the strobe output for the first frame or two kind of defeats the purpose. Whether one strobe is at half power and the other at 1/4 is somewhat irrelevant, to get a true comparison you want the same amount of light falling on your subject.

I think the degree of difficulty varies significantly depending on which manufacturer you are dealing with. The fundamental problem is attaching the Nauticam bayonet adapter to a flat port that you can use on your housing system, I believe that Marelux ports can accept the Nauticam bayonet adapter. You would need to work out if they offer a flat port of the right length. Isotta offer a flat port which will accept the Nauticam adapter and they include the 24-50mm in their port chart, it takes the H63 port. The Isotta ports will fit directly onto S&S housings without any adapter. I had a look at the S&S ports and looks like they might accept a Nauticam bayonet adapter, but the range of port extensions is quite limited. Nauticam port for the 24-50 is 16mm shorter than the Nikon Z 50mm macro while Isotta have a 20 mm difference in their ports. S&S specify the Macro port 15 with 20mm extension ring, so the Macro port 15 might work with the 24-50.

I would also add that in terms of field of view if you look at horizontal field of view - which to me dictates how large an object you can frame, then the WWL and WACP have a field of view of about a 13-14mm rectilinear lens. In a lens with barrel distortion the image is stretched more the further you are away from the centre so the diagonal field is that of a 10mm rectilnear, but you usually don't frame a scene from corner to corner. The horizontal field of a 16mm is about 96 deg, a 14mm is around 104 while a WWL wlll get about 106 deg. A fisheye will get around 144 deg, but may struggle with reach for sharks.

the fiddling is trying to work out which flat port will fit the 24-50. You could ask if anyone has made a zoom gear for the 24-50 on S&S, that would be the fiddly part if you can't borrow someone's design to get printed. Switching to Isotta might also be a possibility to use the WWL-C

This has been discussed in this thread: I'll lock this thread, please continue discussion in the linked thread:

It might be possible to change out the lug ring on the Nauticam port for the S&S lug ring and use it on the S&S housing. Not all Nauticam ports have a removable lug ring and then you have to work out if the port length is still correct on the S&S housing. There will likely be differing depths of the camera flange in the housing between different brands. The WWL-C can only be attached to the Nauticam bayonet adapter which requires the specific geometry of the Nauticam ports m67 thread with the two cut outs. I believe it can also be fitted to Isotta ports which use the S&S mount. Lastly you'll likely need to 3D print a zoom gear. All do-able but requires some data to sort it all out abd some fiddling,

Does the R50 housing have an arrangement like other Nauticam housings where you can pull the gear control out and twist and lock it in a retracted position?