Tom Kline

Look at what Alex is testing!!!!!

I believe you are incorrect. One can certainly focus UW > 1:1. Folks have been doing that for years, e.g., using 1.4 teleconverters or internal (on the lens inside the port) diopters. With domes one is focusing on a close virtual image - this is the distance the camera lens focus is set at and can be read off the focusing scale (with a transparent housing!!!). Many lenses do not focus close enough to allow them to work behind a dome such as 50mm f/1.4 lenses with a typical min. focus distance of 0.45m. This is a big problem as well with medium format cameras. I know this because I have the Hasselblad EL housing that uses 8" plastic domes. The 50 and 60mm wide angle lenses that work with the housing focus to just 0.5m so special Zeiss made diopters were sold. As it took me years to find them I used standard off the shelf diopters that also worked. With a flat port one can typically use the entire focusing range of the lens. For example with the camera lens at infinity (virtual image distance) the lens is focused close up with the amount dependent on diopter strength so further rather than closer.

There is clearly a lot of variability in how people use LR. The lrcat file is generally rather small even in my case with 0.7 million pix. It is the previews file that takes up space and there are choices in how one does this. Some are big while others are small. One can set 1:1 previews to expire as well, which I did not do at first. One can delete the previews file which is the equivalent of starting from a backup file. I did this only once and that was years ago - when I did a version upgrade. The trouble was that I only saw grey rectangles until the previews were regenerated which can take some time - happened when clicking on the folder in library mode. The images appeared sequentially as they were generated. I had only a few 10s of thousand images back then. Just for laughs I have more images of three of the Pacific salmon species than Tim has in his entire catalog - see attachment. Note the large space to the left - those are the higher taxonomic categories further up from order (Salmoniformes). Be thankful if you are not a biology nerd!!!!!! BTW you will note that I have the common name at the bottom of the hierarchy so I only have to type in "so" for Sockeye Salmon and LR does the rest, which I do when importing into LR. If I used the scientific name I would have to correctly spell the genus name and at least one species name letter to get LR to pick the right keyword.

My comments in bold.

Consistent but do not forget the SMC mag is quite a bit higher than what the lens does alone. The real goal IMHO is the large gap in minimal working distance. For example I would not normally use the 105 without a wet lens or internal diopter at this location due to very low viz. At 1:1 there is too much distance, can only work very close. BTW because the MFO is so light and compact it is easy to bring along with an EMWL. I actually had the 130 EMWL with me along with other options I did not use (remote control cable and 45° finder).

PS, It just occurred to me that with the MFO the max magnification is reduced compared to using just a flat port so looked up the Nauticam port sheet. Nauticam states it is 1.1x for the 105 Nikkor AFS-VR with the MFO. But max with a flat port is 1.33x thanks to the refractive effect of water.

Not dry here at all. It took a week but the sun did break out for a short while (remained mostly cloudy) yesterday so was able to give the MFO a tryout - the rain commenced just after getting home! Raining hard with wind now. I also tried out my new float rig (note all the float arms). The UW shots shown here were taken at f/8 with auto-ISO. Note that I did a vertical crop of the two-fish shot. Just the stickleback is in focus. This is in a protected spot as the wind was blowing enough to cause white caps and small breakers on the shore of the main lake body. I stood (with waders on) where the camera is in the setup shot and pole-cammed the results using the camera's intervalometer. Note the brown bottom. Water is stained so that a very heavy hand was used for post-processing. For this shoot I was in the two to seven inch working distance range so right in the range for which the MFO was designed. The bare lens is about a foot minimum distance (Nikon 105VR-AFS F mount on Nikon D4S).

The MFO-1 is listed in the N85 datasheet from Nauticam so meant for micro4/3 as well.

Good discussion thus far but nothing said of the shooting conditions such as light levels and water temperatures. Both of these factors can make UWP quite challenging. I know because they dominate the conditions I typically shoot in (Alaska). Water is in single digit °C with very few exceptions such as the surface waters of a lake during the late summer. I have used mostly gripped camera bodies as a result (big batteries). Currently I am using a suite of Nauticam water contact optics from EMWL to the most recently acquired MFO-1. Also have the SMC-1 with the piggyback magnifier. These are camera brand agnostic. I do NOT do vid only stills.

To the OP: What are your catalog sizes? I have nearly 700K images in my LR library. The image data are on spinning hard drives, two 16 TB drives. This is after 2 decades of digital photography. Files created by PS like when using BSXT go with the raw data on these drives. I use regular previews. The smart ones are quite large is my understanding so do not bother with them. One of the attachments shows my various catalog sizes. Previews size is < 400GB (hard to read since I did some squishing to minimize area I was screen-grabbing.

Ps., almost forgot. Just got the MFO (mighty fine optic) a few days ago as it was back-ordered (from Backscatter). In the bag ready to take it out but waiting for the rain to stop (predicted for later today)

I think Robin D has the right idea. The 105VR lens is no slouch so one has to find its weaknesses especially those when used under water. For example see attachments. A 105VR shot done with a Nikon D800 so 36 Mpixels. One jpeg is of the whole frame. Looks decent at 1000 pixels for the web. Next shot is the upper right hand corner at 300%. I did a screen grab then converted to a jpeg to make the file size quite a bit smaller but still larger than the whole frame shot. The color fringing not evident in the whole frame image now is. One gets more of this (fringing) with out of focus high contrast edges. FYI, chromatic aberration correction was turned on (in Lightroom).

I had a related experience a few years ago from buying a secondhand housing with a threaded lens port that refused to come off. I bought a special strap wrench to try at first and used penetrating oil a few times as well. Then I tried the thermal trick by placing the housing in a chest freezer. Trouble with that was that it got covered in condensation when I removed it as I live in a rainy area (northern limit of rain forest that extends southward through BC to Washington state. Months later, during winter, we had a very cold spell, dry and cold, so the temperature was well below freezing outside. Finally that worked, after a few hours in the dry cold. Humidity was also low indoors so very little condensation.

You probably do not want to use the Mk I (non N) version of the Nikonos 15mm lens for the same reason why adapting many older Leica rangefinder lenses is not such a hot idea. Especially since the Sony cams reportedly have a thick cover glass over the sensor (discussed on Leica forums). This is because the lens is way too close to the sensor so that the light rays hit the sensor at an acute angle in the corners (leads to optical issues such as vignetting, color shits), i.e. the lens is NOT telecentric. Even many film (i.e. older) SLR lenses are not telecentric enough. This was discussed ad nauseum on internet forums in the early digital days (2 decades ago now!). I suspect that even the 15N lens may have issues (it is slightly retrofocus, the opposite of what was stated in post #1, but not to the same extent as SLR lenses (mirror box clearance need being greater than the TTL metering parts (metering first introduced with the N-IV, not the N-V)).

The hood is shown in the link that I posted up-thread. Scroll up and click. It is generic, i.e., no brand. The only text on it is 67mm.

The only marking on it is "67mm" like the first one in this search result: https://duckduckgo.com/?t=ffab&q=67mm+vented+lens+shade&atb=v320-1&ia=shopping&iax=shopping

screws in

I did not want to speculate above but one possibility is gas expansion in the battery compartment pushing the o-ring in the wrong direction. BTW when I take a pressure reading of my housing using the Backscatter model housing sucker part (there is a gauge on it), the vacuum reading tends be lower (!) after use in local water (local mean water temp measured by a graduate student is 5°C). Housing is still cold; it takes hours to warm up at room temp.

I do not have a pic of mine. Keep in mind that 67mm is a very common filter size with many lens shades available. Both for protection and flare reduction. The one I have in the case with my SMC is a vented shade like those made for rangefinder cameras. Possibly to have less drag.

Aquatica as well as Ikelite use inch sized bulkheads. Mostly likely because the tools for inch sizes are more available (and cheaper) in this part of the world. Certainly easier to find locally in hardware stores, e.g. taps to thread the holes.

I use a lens shade in the threads of my SMC-1. Probably a good idea with the MFO unless one is overly concerned with extra drag.

Your story reminds me of one from a few months ago involving Retra. Diving on more than one day without opening and re-sealing. What can happen? One can only speculate. I have done multiple dives many times without changing batteries in my strobes within a day but not with a time gap of an overnight. I have for the camera housing (two days diving (as well as stream shooting) without recharging or removing cards).

Nice shot. I have been able to take group shots of salmon etc. schooled up and generally not moving much but it does take some time for them to get use to the camera which I keep on the bottom (negatively buoyant). There are many examples on my website in several galleries.

I have mainly used wired remote controls made by Seacam for my work with both Nikon and Canon DSLR cameras. The Seacam release stick is two-stage like the shutter release button on a camera. First the AF is turned on (camera woken up if needed) and second the shutter is triggered by additional finger preassure on the button. This allows one to finesse the AF so as to get the fish in focus at the right moment. I have not used anything via USB but over the past Christmas holidays at my sister's I used my ipad mini to trigger my Nikon Z9 remotely using the Nikon Snapbrige app. wirelessly. That worked only fairly. A lot of misses due to sluggish response as well as poor haptics via the screen release. As well the app frequently stopped working even with only glass (sliding door) between my ipad and the camera at just a couple of meters (close range). I did manage to get a few good shots of some Virgina wildlife at a bird feeder this way but I did shoot thousands of pix. Examples are on my website.

Getting more magnification generally means getting closer (keeping the same lens). One will get more magnification along with greater working distance using a longer focal length lens. But they are more difficult to use due to the narrower angle of view one gets with a longer focal length. There is no free lunch. Also using a diopter instead of a teleconverter (TC) will yield a larger working aperture, i.e. brighter (if this is what you meant by "allow more light onto the lens"; lens shades are used to avoid this as this is generally a not desirable). TCs were used quite a bit to get greater than 1:1 a few years ago).