Tom Kline

Done. The button label looks like a cartoon call-out. BTW, before seeing this I did not know you are responsible for the new vid show, thought it might be Matt's!

A serious blast from the past! An actual table of contents for an internet thing!!! Nota bene, a table of contents is something one typically found near the beginning of books. Claude, however, is far from perfect. See the Seacam entries at https://wetpixel.echeng.com/companies/seacam/. "Both (viewfinders) were available for all Seacam housings..." The Seacam Silver housing for the NIkon F5 was offered in versions that did not take the interchangeable finders but instead had a flat window for use with an F5 with an Action-finder attached (DA-something, I know because I have one). As well, the remote system started a few years earlier before it was shown at DEMA (2007 as reported in the Wiki) because I was able to order my D2X housing (late 2004 or early 2005) with it installed (ordered retroactively during the 9-month wait it took). I seem to recall the remote was announced alongside the Seacam housing for one of the Canon 1D cameras (either 2 or 3 series). When I saw that on Wetpixel I called Liz at SeacamUSA and asked about adding it to my housing as well as the big question for me: Would it be able to be used with longer cables than the lousy 1.5 meters of the RS remote control (which I had at the time). The answer was yes and has been at the core of my digital UWP.

After making the above post I saw that there was a big error in my hiearchy which I have just fixed. Fishes was in the wrong place. It was an easy fix.

A hierarchy is useful for doing the whole taxonomic nine yards. Here is an example from my LR catalog. I only have to type in pi, the first two letters in pink, and LR often gives me pink salmon as the first choice. Select that and all the higher bits are automatically added on LR export such as when generating jpegs. Note that I have over 91K pix of just that species but the number above is smaller. It is possible to equalize the numbers but it is time consuming so I have not done it for a while. As well you will note the mixture of English and scientific names. This is so the English names for higher taxonomic groups also get included in the key-wording. The includes some rather obvious words like vertebrate. I have been using LR since version 1.0 so this is a fairly developed KW list. It is VERY easy to modify. Just drag the keyword around in the list. Put it under the KW you want in the hierarchy. I have done a LOT of modification over the years. This includes having to deal with taxonomic revision such as for the mantas a few years ago. Often have to fix spelling errors! Need to do some clean up as well - the fish prey KW needs to be moved or deleted. I use the # symbol as well as all caps to designate a division in the KW list just to keep them more organized. It can selected (via a dialog box) so that this not exported hence it is a non-keyword.

Looks like a potentially useful tool. Looks like I will not be able to use it as I have Intel macs (tower and laptop) and will NOT be updating my pro model anytime soon (very last Intel model). At any rate it looks like you have loaded up on beta testers. I think the way to do the test is to make a "daughter" catalog for one area. I have done this for Hawaii and loaded it onto my laptop for a trip to HI. I was thus able to use existing keywords as well as see what I already have in the way of pix for a given spp etc. as I imported new images. New pix were in a new folder in this catalog. On return home I made a daughter catalog (selecting the new folder) on my laptop which was then imported onto my mothership (tower computer).

I have the adapter Chris mentions. There are several versions. I have used three versions thus far. One of the first two might work for you. It is a bit of a Rube Goldberg with both fiber optics and a cable, one on each side of the adapter that dangles in the middle. I found this to be not rugged enough for my use in Alaska. The third version screws into a Retra starting with the gen 3 models so does away with having to use fiber optics. This is what I am using now. One thing you should know is these adapters are for manual use, no TTL. I suggest that you use a strobe that takes N5 cables. This is the only way you are likely to get TTL flash which was more useful with film than with digital as there is no chimping with film. There are loads on the used market for not very much. The last new model was the Nikon SB105 that was introduced to replace the recalled SB103 so are likely to be not too used. Make sure to have back up synch cords on hand as they do eventually fail.

Looks like it may be an Acropora. Really need a close-up shot showing the ends of an arm. As well it looks like a fairly young colony (small size - few polyps) so may not have developed much of the 3-dimenional aspects of one that is more developed.

Shorting out the triggering contacts should trigger the strobe. This trick can also be used on topside strobes. Some (mostly older and studio) models will generate a significant arc. Make sure to have the strobe power,on for a while to reform the capacitors - 30 minutes should work.

Nice report! A basic tenet of underwater photography is that one needs to minimize the water distance between the camera and the subject. Therefore the angle of view of one’s optics needs to be proportional to the subject size and therefore the focal length inversely proportional. A 200mm focal length macro lens will be great for shooting butterflies topside but mainly useful for tiny subjects under water. Aiming and focusing a 200mm will also be a bit more challenging than shorter focal lengths.

I think it is now more important that ever to sign one's works to "humanify" them. Hence a watermark. This can be forged as well but if there is an authorship question the author can be contacted to verify. It is only a matter of time before AI starts adding imperfections - a speck of backscatter here and there for example. Easy to ID species will be less problematic for AI compared to others. I invite people to look at dichotomous keys to see the types of minutia that may be needed for others. Some require looking inside as well as I recall a fish key I used in a class that showed up during an examination that required knowing the peritoneum color.

Tariffs strike again!

I wrote it live so to speak but I did have to scroll up and down quite a bit to see the prev mssgs super keyboard challenged

somehow I screwed up and the text goes beyond the page!

Another data point: I have the book titled Free Diving by Rebikoff translated by Mervin Savill. Published in London 1955, first published in 1952 in French as Exploration Sous-Marine Ch. VII (the last one) is titled Underwater Photography and Filming. He writes a lot about his underwater flash units but not a peep about corrective optics Interesting that Ivanoff lived so long but what did he do from the 1960s onward? Searching his name I came up with a living artist. Another data point; See: https://www.spiedigitallibrary.org/conference-proceedings-of-spie/9192/91920P/Afocal-viewport-optics-for-underwater-imaging/10.1117/12.2061445.short Read the abstract!!! He calls them "the Ivanoff corrector lens" Lens is a bit vague since it can be one piece of glass or a whole unit like a camera lens, but for lack of a better English word lens has to be used (Abstracts often have a word limit (based on a lot of experience)). This is from 2014 so relatively recent. At Chris: the Nikonos opinion is from a current web page so would seem to be not too out of date but maybe limted to the experience of the author(s). I remember when the blue housings were released! It was during the 2 years my family lived in the US (Germany before and Japan after) when I bought the Hasselblad issue (house magazine) on it at a local camera store. This was between Sept 1970 and August 1972. So it is about 2 decades post Ivanoff earliest dates from the patent. BTW the first Hasselblad to use the 38mm lens was called the Supreme Wide Angle or SWA. The SLR was the 1000F. I have seen a SWA in person - it had a more primitive shutter. From the early 1950s. The SWC, the later camera, has to be used in the blue housing that takes the corrector lens. SWC/M and newer, no, because the tripod mounting shoe was moved to allow fitting of Polaroid backs.

Happy Thanksgiving! Thank you Alex. Not surprised that Zeiss may have made some improvements, but a doublet (2 elements glued together) for the port would also need to consider pressure resistance. How would hydrostatic pressure affect the glass at the contact surface between the elements? Lens element separation is bad enough in air (have seen Z optics with this problem - both camera and microscope). Thank you Adventurer. The 2003 article is interesting but may be misleading. It would be good to know how the author obtained the quoted material. It seems unlikely that it is from his memory if from 1968!! Rebikoff may have worked with JYC but it is Edgerton that JYC called Papa Flash. JYC is known to have had custom built underwater housings for his motion picture work. If Rebikoff worked with Ivanoff to invent the I-K lens per this article why is Rebikoff not in listed in the patent (other names (Grand and Cuvier) are)? Rebikoff may have outlived Ivanoff so had more of a chance to blow his horn (as well as being the book author). Also note the differences in the figure captions I previously posted. System Ivanoff in 1955 then called Rebikoff correction lenses in 1965! For the same items. R does show the smaller lens (actually two of them) on his stereocam. R may have built the cam but I more likely (his company or his associates) the lenses that are part of the housing. Thank you Davide. The Fathom unit seems to work more like the recent Sea&Sea correction lens as it is designed to work with a dome port but with 3 lenses elements so may be even more expensive. The S&S lens is aspherical and maybe it is doing the same job as 3 that are spherical. Thank you Chris. These lens were first developed by 1955 as that is the date of the earlier book and there are more examples in it. The patent was submitted in 1951 (in France apparently), received by USPO in 1952. Suggests a bit earlier than the 1960s.