All Activity

Thanks Tom, the point I'm trying to make is the earlier lenses, be they from the 50's or 60's are likely not as good as the Carl Zeiss version which it seems was designed in the 1970s when computer aided design and new optical glasses were appearing. This would possibly explain the remark the Inavnoff-Rebikoff correctors were not as good as the Nikonos lenses in the books. Regarding doublet lenses perhaps yes if they are cemented doublets - they could have been air spaced doublets perhaps? Air spaced doublets provide an extra degree of freedom in the design due to the air space. If the front element were strong enough to resist flexing due to static pressure, as long as the join was inside the housing it would work as well as any cemented doublet I think? I understand cemented doublets become problematic in larger sizes and they were used as the polish and coatings required on the cemented surfaces were not as demanding as the cement filled defects and also avoided reflection from the two cemented surfaces.

Are you asking about an image taken with it? There would be no reason to use the speedbooster with the 8-15 as you lose zoom range and you would need to zoom in to about 11mm or so on the lens to get a full diagonal fisheye equivalent to an 8mm fisheye. Between 8 and 11 mm you would have a partly cropped circular fisheye image which is really not usable. The smart adapter gives you a full frame fisheeye through to about the same filed as a full frame 28mm rectilinear lens, so a m43 system gives you the 8mm fisheye and the 7-14 reach in one lens. The speed booster is useful though to mate with the tokina 10-17 it will produce frame filling images from about 11 to 17mm. Without the speed booster (using the smart adapter with no glass) it would not give you a full fisheye field at miniumum zoom , the view would be noticably narrower.

Thank you @Davide DB , it was on multiple gorgonias, so I'd suspect the gamete release to be more likely.

I'm rather interested in the 8-15 on my EM1-II, despite having a WWL-1. Does anyone have an example image of it without the speedbooster and with?

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.

Thank you so much for this!!! Looks like I can avoid getting new ports! I already have the 30mm N100 extension from when I used WACP-C, and have adapted over to use w my new canon 8-15 setup. So I can reuse all my ports and only need to buy the new lens itself it sounds like. Great to hear this setup can work w all the Nauticam wet lenses (of which I have all).

Metabones currently offer a type 2 adapter which will fit the OM-1 this is the m43 to Canon EF lens adapter. The Nauticam N85-N120 adapter for Nauticam ports was designed to use any Canon EF lens with any m43 camera, but they chose to design the adapter for the speedbooster, which was not needed for the 8-15 and adapting other EF lenses to m43 was probably not required as the m43 manufacturers have a very complete range of lenses. There's no shortage of second hand 8-15s though and they are not that hard to find for sale. I think it's more likely that Nauticam decided that WWL/WACP etc were the future for them so trimmed the range of offered ports and adapters. It's a pity as the 8-15 on m43 is an excellent option.

I suspect there are many versions of this lens floating around and design capability for optics has expanded quite significantly since these were originally developed. The statement above quite likely refers to what was available in the 1960s. By the 1970s the possibility of computer aided lens design appeared and was likely used with the Carl Zeiss lens Alex has and likely they were able to improve it significantly with additional elements or other changes like newly available optical glasses. So the newer Inanoff-Rebihoff correctors are likely to better optivally than the simpler ones designed in the 1960s.

Unfortunately I don't have blackwater experience. The 30mm Panasonic seems snappier than the 60mm but I haven't used it for a while. I do know that the 60mm AF is better on the OM-1 and even the Em-1 mkii than the earlier bodies. I think the main reason for the shorter macros in blackwater is the wider field making finding your critter easier. From what I can see the 30 and 60 mm use the same port and you just add an extension tube for the 60mm so it's just the lens cost to add the 30mm.

I have the special port and zoom gear plus 12-50 lens, it really is a generalist. I mostly use it I'm the macro port with a diopter however. I haven't tried it behind a dome. However I'd be looking at the 60mm macro and MFO-3 for everything except wide angle. The WWL-1 works really well with the 12-50 other than needing a little zoom in plus it's a heavy lens. If you have the 30mm macro then the Weefine/Kraken KRL-09S is a lighter wide angle option.

being completely different from the Zeiss design of Alex, could you share some photos taken with this lens? Is it this one? Fathom ImagingCorrector Optics - Fathom ImagingCORRECTOR OPTICS Field curvature generated by a concentric dome port can be eliminated by inserting a precision lens assembly, “Corrector Group”, near the dome port concave surface. The “Corrector Gr Their patent: https://fathomimaging.com/wp-content/uploads/2020/10/Concentric_Dome_Port_Correctors.pdf

Yes, very rectilinear Davide. My optical glas may be a slight variant, though. As @Tom Kline asked for more historical quotations, I have found the following interesting recent writing from 2023, confirming the two-step process this optical system has gone through and what Alexandre Ivanoff's later role played in the 2-step invention. It's in fact the complex chromatic aberration correction lens element, that @Alex_Mustard had get measured and failed to reproduce with normal diopters. Have a read below... source: Photonics Focus Magazine: Article on Page 14 by By William G. Schulz

Thank you Sevag, I will contact you directly as soon as I am back at home. Also the second HF-1 died finally after few dives. Currently I have a single MF-2 strobe with snoot and can make macro (still 2 diving days left and on Sunday, November 30th I will fly back home) ...

Considering the current/old adapter does not fit on the OM-1, and there is no longer production of the EM-1, perhaps the adapter is discontinued pending release of a new version that does fit? I have no idea if there is sufficient demand. On the other hand, the Canon 8-15 is also discontinued, so perhaps the whole concept is pretty much at a dead end from nauticam's perspective.

The Zeiss one is definitely more complicated. The front (main) part is not simply plano-concave. But it two elements sandwiched together, with the outer element being slightly convex. Also the internal lens is not a simple positive lens - but matched to the outer lens. Worried about loosing this lens, we measured its strength and made a simple replacement matched to the same strength, which didn't work anywhere near as well (showing there is something more in the design). I know that I shared a lot of stuff about it on Wetpixel at the time. That Tom also contributed to. Search Ivanoff on Wetpixel forums - e.g. https://wetpixel.com/forums/index.php?/topic/54681-full-frame-slr-wide-angle-corrector-port-tests/&tab=comments#comment-356001

That photo shows my camera before a blackwater dive, but the strobes are not in their shooting position - they are in their carry to the boat position! I generally shoot BW with the strobes pushed out wider than this, just in front of the port (as shown) and aimed in at around 45 degrees (again pretty much as shown). Ideally translucent subjects show up best with the light coming through them from behind, whereas more solid subjects show up better with more front lighting. This position is a good compromise for both (as a starting point). When shooting the MFO-3 as a main lens on BW, yes, I would have the strobes a little further forward still. Hope this helps,

Hi Alex, I believe now you are always using MFO-3 in the blackwater, considering the focal area change, will you also change the strobe position a little bit or still keep the same as what you showed in this pic?

If you want a simple, do kinda everything solution, I'm a big proponent of the Olympus 12-45 in a mini-dome. The domes for the 14-42 / 9-18 or 8mm (with an extension ring) both work. Other than ultra wide or true macro, this combo is a do everything generalist. If you want ultra wide, bring the 8mm. If near-macro isn't enough, AOI macro ports are cheap and so are used copies of the 30 or 60. Used copies of the 12-45 can be found all day long for less than $400, and you get Oly Pro build quality, autofocus, etc. Can you tell I'm a huge fan? I currently shoot the 12-45 in an AOI OM-1 mkI/mkII housing with an Inon fisheye dome, and I could be perfectly happy with nothing else.

Hi Chris, fully agree with MFO-3's advantages, I used in my last dive trip together with new Sony 100mm macro, really incredible result, even it was my first "real" blackwater dive. But considering to have two MFO-3 is a really "Crazy" idea😊 I know you have very rich experience on various macro lens for M43, just want to know the overall impression between 30mm and 60mm+MFO-3 for the blackwater? Focusing speed, focal length, FOV, etc. Big thanks in advance~

Based on what he told me it sounds like that's probably what he means as he mentions physical interference between the adapter and the viewfinder: The MB_EF-m43-BT2 does not fit to the OM System OM-1 due to the physical interference between the adapter and camera body(viewfinder). I already had to grind my adapter a bit as well for it to work with the Isotta housing so that's not an issue if I need to grind more.

I I really not sure what version I have, it's not a Mark II, I recall I downgraded the firmware to an older version as I initially had some issue running a big Canon tele lens. But it works perfectly well now. I ground down the adapter a bit, you can see it on the first photo in my post linked above to allow it mount on the OM-1, the viewfinder section on the OM-1 projects forward preventing it from mounting. Maybe that's what they man by being not compatible. I bought the adapter second hand. I do see they have the latest version on sale on their website for $US399 today. The STL file is linked in that post to print the gear.

They both take the same Nauticam port. If you want to minimise things and are into mostly macro the 60mm plus and MFO-3 would be the preferred solution I would think - it comes in handy when you find a larger subject when using the 60mm, think Anemone fish and even larger nudis and scorpion fish - like a Rhinopias. You have to back off too far with bigger subjects. I used it today for a 90-100mm long nudi, much less water between me and it, likewise a 130mm long seahorse. And you can put it on for blackwater. Then you don't need the 30mm.

price lowered another 3%

I have no experience of M43 UWP, but theoretically it must be more powerful than TG series in most cases. Consider over 85-90% of our diving is only for macro, we rarely need to shoot macro and wide angle just in one dive even for the dives at the same day. Which means, I don't have to consider to use one lens fits for all, and if the existing wet lens can be used to enpower the entire setup, that's great, but if not, I'm also fine with that😀 Since the marco setup is much more important, I'd like to know: Does 60mm is enough for both normal macro and blackwater, or 30mm is recommended for the blackwater? As what Chris mentioned, panasonic 30 might be a better choice, but anyone has chance to check whether it could fie the same port as OM 30mm? It is 63.5mm in length, 3.5mm longer than OM 30mm.

Oh wow I just realized your custom zoom gear uses the housing knob and so eliminates the need for the knob on the adapter at all. That is much better as it lets me use whatever is the closest in length to the original setup.