Tom_Kline

A quick update. I got a pair of ULCS handlebar clamps to hold the fiber optic adapter close to the strobe. I got some Toslink cable. Toslink is a tad stiffer than the stock fiber optic. I tried one more time to fix the original fiber optic and failed again. Then I cut a short section of Toslink and on the first try it worked. I suspect the issue was with the fiber optic. The spot were I took the photos got no sun just a couple of weeks ago. You will note the one with a shorter fiber optic is on the left, which is the Toslink.

If you still have your SLR housing you could focus with it, turn the camera off, then check the focus distance on the surface. Use that distance with your Z6. You will need to use the same dome with both housings. I tried using this pre-focus approach early on in my digital underwater photography using the 14mm MF lens - got too many OOF pix of salmon so gave up on that lens. Got the 14 AF!! The technique might work better for larger subjects like blue whales. Since you already have the lens it will not cost anything to experiment other than your time. You could write Nikon and complain about not having an FTZ that does screw-drive AF.

PS. If you use a flat port it will be like a 1.33x increase in focal length so your field will be narrowed compared to a dome.

Since you are using APS-C a flat port will work with these focal lengths and so be less challenging to set up. I have a 7D2 and have used the Canon 24 and 40mm pancake lenses with it when traveling but I have not used them for underwater photography. Is your query about these lenses? Since these lenses are so stubby it might be an issue properly adapting a dome port to them. Their entrance pupils might be closer to the camera compared to your 15mm lens which I am guessing is a fisheye, the Canon model? You might want to ask Ikelite about what you want and if they have specific recommendations for your lenses. You need to be more specific about your gear when you communicate with them. Other 24 and 40mm lenses are much larger than the two Canon pancakes so would take different port setups.

Good question!!! It is the fiber optic cable that came with the strobe. Oskar told me: "The optical cable we are using at the moment is a multi core 613 type which has an official bending radius of 1mm." The more recent failures were not due to obvious cable breakage but much less light came out the failure end compared to the other strobe after attempting repair after the fiber optic came out of the adapter while it was in the bathtub when I rinsed the setup after my shoot. One troubleshooting step is to unplug the fiber optic cables from the strobes and look at the ends while firing the camera. I have ordered some Tos Link cable (suggested by another Wetpixel thread) as the original cable is getting short.

The angle of a given lens, fisheye or not, should be the same behind a dome port as shooting the lens normally (in air). To work properly the dome must be properly configured to the lens and the lens must be able to focus on the virtual image generated by the dome. This is NOT like a flat port. See: https://www.scubageek.com/articles/wwwdome.html

I would like to report some success with the new Pro. However, there were two more failures requiring re-termination of the fiber optic. I did two outings. First, looking at nearby freshwater sites but all were quite frozen where it was deep enough to shoot so I was forced over to the harbor that has floating docks and stuff growing on them. So went into a polecam operation. In the topside pic you can see the tide was a few meters lower than high tide (where the snow ends). I made a shear guess: shot both strobes at 1/4 power at ISO100 at f/11. The histogram was well-centered so just did this one site. I am showing both the full frame and a blow-up so it is possible to see that there were mussels in the shot! Used the RS28mm lens.

I have a further suggestion for the adapter. That is to make it possible to bolt it in place. For example, have the diameter be thicker where the set screw is located so the side opposite to the set screw could be flattened a bit, then drilled and tapped for either M6 or 1/4-20. One could either bolt something on directly on or use a ball fitting similar to the one on the strobe. M8 would be overkill. For example: https://www.unterwasserkamera.at/shop/catalog/en/product_info.php?info=p1630_u-l-c-s--ad-6-ball-adapter.html

Oskar, Thank you for your reply. I had success times two but before that let me address your question. The only twisting was incidental. Nothing at all like described in edit 1 which I did not see until after doing the repair this morning. The strobe was mounted on a ball at the top of the housing (ball normally used for pole cam or focusing lights). So the only movement came from plugging and unplugging the plastic end into the strobe and incidental movement to move the cabling out of the way - I used a standard curly Seacam S6 - S6 cable. After the initial failure I started swapping strobes so there was a little more movement of the cable. First the old model. When it failed I got a Seacam S6 - S&S cable which I attached to the opposite bulkhead to confirm functionality of strobe and camera which turned out OK. Then I went for the second adapter - at this point I had not yet opened the box containing the 2nd strobe plus accessories. Number 2 worked OK as I described yesterday. Today. I first fixed the problematic adapter. It was challenging to remove the broken bit. I found success by using a micro screw driver to wedge it out about 0.5mm. I was then able to grab hold of it with a small needle-nose pliers - the one I had in my UWP tool kit. The transparent part came out first. Following a little more digging with the screwdriver I got enough of the black part out to grab with the pliers. The screwdriver I used as well as the two parts of the cable that I removed are in the attached pic. One can see the wear on the ends resulting from my extraction technique. I then attached it to my housing after mounting the old strobe. Made sure it was on SL and it worked! I think I had it on to just "on" yesterday. So success on both the cord as well as the old strobe working via fiber optics. My suggestion is to have the hole at metal end of the adapter part be of dimensions compatible with the plug that is on the strobe end of fiber optic and use the same plastic part on each end. Think double-ender like a Viking ship. One could unplug the fiber optic part from the adapter part for traveling making them easier to pack. Fiber optic cords could be packed separately into a more or less flat compartment. This would reduce stress on the fiber optic part since it would not have a heavy object attached to the end (the adapter part). People like me would be happy if you sold the plastic plugs by the boxload (2 dozen or even 50!). I like having backups plus the cords could be made for different lengths. The set screws could even go in a small ziplock bag saving the labor of installing them. Thanks, Tom

I have some S&S connectors as well but they are of the wired kind so do not work on the new strobe models. I had some trouble getting my new strobes to work. Optical adapter #1 would not trigger yet I could see the red flash at the end of the fiber. I tired both of my new pros as well as one of my originals. No dice. To make sure it was not the camera I was able to confirm the strobe worked by using the wired connector. Then I unpacked adapter #2 and it worked on the new strobes! Was able to fire each pro but not able to fire the old Retra. So looking more carefully at adapter #1 I noticed red light coming out from around the fiber cable where it comes out of the adapter but did not see this with #2. So I decided to re-terminate #1. While looking for a matching Allen wrench size to loosen the set screw the cable broke off completely - see pic. Looks like a very bad design to me if the cable crimped where it comes out from the adapter. It might be better to have a bigger hole to match the one on the strobe fitting and have the same part on each end of the cable. This would make exchanging cables at each end much easier. I am not sure how to proceed now as there is not much to grab on to. The fiber optic did not just drop out after loosening the set screw. I tucked in the broken end of the fiber optic under the velcro strap for the pic.

We will have to hear from Oskar. Meanwhile I was curious about the black cap over the optical sensor. I have never used these on my ori. Retras and have only used the similar part on my Inons when using them as slaves. The Inon part fits on the Retra Pro but the Retra part does nor fit on the Inons due to the larger diameter of the sensor - at least on the Z220 model. The hole in the Inon part has a larger diameter.

Yes that is what I was referring. I seem to recall from when I ordered the strobes that two fiber optic cables could be used but that one would be included with each adapter.

Mine arrived so just starting. Fiber optics are totally new to me too. Was not able to find the "app" either via Google using Chrome on my computer nor the Apple app from the Apple App store. There needs to be a back up maybe a pdf at the Retra website? Trying to figure out how 2 fiber optics are attached to the adapter. Is the part that inserts into the strobe a standard part?

FWIW my DHL bill is 110US for two pro strobes plus two synch adapters. As well, DHL has to mail it to me since I am in the boonies.

FWIW I have FW version 2.20 in my Z6. Since FW update affected the AF it could be significant for these TCs.

I have not shot any pix with the 8-15 and TC so cannot comment on image quality. I removed the lens shade during my test yesterday. Note that the shade will cause strange vignetting at wide settings. It is interesting that my oldish TC is AFing just fine on the Z6.

Got a DHL call today! Now if our airport does not shut down like last week!

I use FF mainly for very high ISO. I use 12800 a fair bit (35.5K of 315K underwater images according to LR) as that is the upper limit I have set for auto ISO with my Canon 1DX which is now somewhat old. Have used higher but then needed a very heavy hand at noise reduction. I am also shooting FF Nikon mainly for the RS lenses. Does the OP have a high ISO need?

I do not have your exact set-up. However I just now tried my Z6 + FTZ + 8-15mm - That works A-OK. Then I inserted a Kenko 2x converter that is a number of years old (probably close to a decade). I bought it for the old 105D Micro-Nikkor before there was a 105VR. It is called "2X TELEPLUS PRO 300" on the top surface and "KENKO N-AFD Made in Japan. DG" (the first D is smaller sized) not quite on the bottom (towards right (grip) side). This combinations works OK - was able to AF. The aperture readout in the camera is 3.5 to 4.5 when set wide open so is NOT reading effective f-stop.

No problem ;->> Delete "very" from my earlier post! :-< Yup under water we want to shoot subjects that are about 1 foot to 1 meter away if at all possible. Especially with flash. One needs alternate techniques such as slaved strobes or more ambient light for greater distances IMHO. Pools have their challenges as well.

The super long arms was an absurd suggestion of course. Possibly slaved strobes placed very 1.5 m to the left and right might have helped. Lighting up a large flat surface with strobes under water is problematic, e.g., walls. BTW I have taken many fisheye shots using just one strobe at the 12 o'clock about a foot above the lens optical axis A-OK. Subject is at point blank range. Seacam strobes with diffusers work rather well. Inon strobes (Z220) with their flat diffusers not so much

Glad you found the lens to be sharp. Not sure of the point of the light fall off measurements. The corners of the pool were at a greater distance than the middle, i.e., > 1.5m. Maybe with super-duper long strobe arms so that each strobe would be halfway to each pool end from your position ;->>

You would not be able to focus the RS 13mm on a Z camera with the current FTZ adapter. The RS used a screw drive AF.

I think that making such a decision is rather complicated today since we appear to be in a transition between single-lens reflex cameras to mirrorless cameras. As well, 2020 is a summer Olympics year when Canon and Nikon have historically started new generations of SLR cameras. Both companies have already pre-announced their new top tier sports cameras, the 1Dx3 and D6. These cameras will no doubt have superior AF among other particulars when compared to the current cameras. This new AF technology will likely percolate down to the lesser models, much as the D850 uses some of the technology of the D5 and the 5D4 uses some of the technology of the 1Dx2. In my 1.5 decades of digital underwater photography I have only been current for about 3 to 4 years. Right after getting the D2X and right after getting the 1DX; I am still using the 1DX. It is very challenging to keep up with the technology unless one has rather deep pockets. The old model depreciates rather quickly as well. Since a new housing is generally required the old housing depreciates alongside. It is something like 50% per generation (but there is a lot of variability here). So buying the latest and greatest today needs to be done with this caution in mind. I have preferred the integrated grip large battery models. These are more expensive as well as larger in size and weight. The overriding reason is that I shoot a lot in water that measured on the C scale is generally in the single digits, i.e., < 40F. As well I may keep the housing submerged for many hours at a time in one spot - shooting by remote control. The big batteries loose about 30% of their capacity due to temperature - Based on the rise in % displayed in the camera upon warming up to room temperature after a shoot (I give a housing several hours to warm up before opening to remove the memory cards). The reason for me shooting both Canon and Nikon has more to do with the histories of their product lines over the last 1.5 decades than what is current. If I was choosing today Nikon would be ahead due to the availability of modified Nikonos RS lenses as well as the 60mm AFS lens which I have found useful. The normal focal length Canon macro lens, which I have, does not allow for full time manual focusing. Other lenses are about the same right now but Canon had the 8-15 for quite a few years before Nikon came out with theirs (I now have both). I think what is needed for mirrorless is a killer app lens for us UWPs. https://en.wikipedia.org/wiki/Killer_application Such a lens could be a 50-150mm macro zoom that went to 1x at 50mm and 3x at 150mm. It will be expensive 2 to 3K, maybe even more. It may be that 16-35 mirrorless lenses are less problematic behind domes than SLR lenses but we need more data before making this generalization. A bit of good news on the Nikon 24-70 Z kit less is that it focuses close enough that a diopter is not needed for smaller domes. It is quite good for topside close-ups based on my experience. Forget the more expensive 2.8 24-70 that focuses to 0.38m like its SLR cousins.

Yes it is fairly long. This is solved by stacking port extension tubes as needed per Tim's point. The above photo shows how I use it use with just the zoom ring which is near the lens mount. Something like this should work with most housings once you get the appropriate gear for your housing. The focusing ring is more problematic since it is quite far from the lens mount. Special tubes incorporating a focusing knob were built for this (used also for the 200 macro). As well one needs a gear for the M-A ring that you see here to switch focusing modes. The older (non AFS) 60 and 105 macros and a few other lenses also have these rings so you may be familiar with them. I have the lens set to minimum focusing distance (lens is thus shown at maximum physical length) and the ring set at A effectively locking it here so long as AF in the camera is set to off. Also on the lens is the Nikon close-up lens No. 6T. I used the UV as a lens cap when I removed it from the housing then later found a 62mm cap to go on so I am using the "belt and suspenders" principle by leaving both on. The 6T is hard to find so it is a good idea to protect it while out of a housing. It is quite thick and does not fit in a standard filter case so I store it on the lens. With this setup I can vary the magnification using the zoom while holding the rig in a fixed position - this minimizes water movement between the port and subject. Working distance is just a few inches (working distance can be changed by using the other T close up lens (it is either plus or minus 1 from 6) or by focusing). Hidden under the zoom gear is a rubber ring that Nikon installed when I had them remove the tripod foot that is not user removable.