Chris Ross

I would at least send them pictures and see if they still try to deny it.

I looked at the the two pics from the corners in that post I linked above and didn't see anything that set the world on fire. Please show us the images so that we can see the improvements. Otherwise we can agree to disagree.

Probably the coolest point of the lens, the vapor re-distributed once it could condense somehere colder, likely the alumnium which would possibly cool faster than the glass. I think it shows there is a trace of water in there- which would be salt water and has perhaps left a light water mark. In any case likely unusable?? If that's the case, little to lose from attempting a repair I think. You would probably need to pull apart to measure o-rings to replace. The current specs say it's 3 group 4 element lens, which means one of the lenses is a cemented doublet quite likely so an additional possibility is breakdown of the cement, possibly caused by water entry. If you do pull it apart be sure to properly label everything so it goes back in the right order and right way up. You will need something like this to remove the retaining ring: lens tool I'm not sure how the seals work in these types of lenses, they might have o-ring on top pressed in by the retaining ring or is it might be like the way front elements of flat ports are sealed. Only way to find out is to remove the retaining ring.

You would need to warm it to maybe 40° to see if it disappears, it is sealed inside and the outside humidity should have no influence. It could also for example be components in the o-rings which have leached into the air space, not too different to the way cars used to develop a film inside the windscreen due to plasticisers evaporating from the dashboard. To be clear also, the point of the dewpoint calculation is to seal inside air that is dry enough it won't condense when diving. If the dewpoint is 7°C then you need to take it into water at least that cold to cause condensation and that should disappear when it warms up to room temperature.

Warming up won't cure it, just prove that it is condensed water. On the topic of avoiding fogging you can refer to a dew point calculator. For example at 15°C and 60% humidity the dew point is 7°C. so working in conditions like that should have a good chance of avoiding fogging unless you dive in the cold waters. You could probably achieve this in an air conditioned room with the AC maxxed out and you could also place the components in a small tub purged with air from a scuba tank (very low humidity) for assembly. Here is a link to a calculator: Omni CalculatorDew Point CalculatorCheck out the dew point calculator to calculate the highest temperature at which water vapor condenses.

Yes this is the one, the removable shade is needed if you want to use circular fisheye. BTW, I disagree with the premise that millimeter precision is required in positioning domes to the lens entrance pupil, for one thing it's difficult to measure it to this accuracy and while the photons to photos page is sometimes referred to, the optical diagrams there are extracted from patents and the actual lens might be different. Also fisheyes work differently to rectilinear lenses in that the line of sharpest focus is an arc rather than a straight line which more closely matches the virtual image shape. By all means get as close as you can in positioning the dome but it is a case of diminishing returns. see for example this post: On the topic of using TC to achieve a fisheye zoom, it's marvelously flexible tool, I use an 8-15 with a m43 camera and it gives me full 180° diagonal fisheye through to a 28mm equivalent rectilinear. Great for switching from for example shooting a large sea fan to turning around to shoot a passing shark then getting in close to some clown fish in their anemone. On the topic of WACP-C I think the images are not what you would call bad, just not as good as the 8-15. To me the main issue is I wouldn't have the 180° diagonal fisheye with the bold perspective it offers, which is why I went with the 8-15 and not a WWL. the issue with the WACP is mainly that its design requires a limitation on entrance pupil of the lens which means it requires smaller kit lenses. Thus, the statement that many premium WA zooms surpass it in centre sharpness - but they suffer in the corners. The newer generations of rectilinear WA zooms particularly from Sony are much improved though as they focus much closer.

All of these diopters would be sealed using o-rings I would guess, so it's possible a minute amount of water has entered - probably just a trace amount. If it's water vapor condensing then it should go away if you warm up the diopter a little. Of course it will come back when it cools off but it proves it is likely to be water vapour. Regardless I think taking it apart and replacing o-rings would be required. You would need a tool to remove the retaining ring and be able to source replacement o-rings to fix it.

This was in answer to your questions regarding the Sony 2x with 8-15. That is possible as the Sony-EF metabones acts as a 26mm spacer to allow you to add the 2x or 1.4x and the 8-15 still focuses. Remember in a dome you are focusing on a virtual image so are focusing very close. You would think that having a spacer between the 1.4x or 2x and the 8-15 would not focus, but testing on Sony systems using a Sony 1.4x or 2x on the camera then a metabones adapter then the Canon 8-15 shows it works perfectly well and the image quality with the Sony 1.4x is better than using the Kenko. If you could replicate the same spacer as the Sony setup with Metabones and the 8-15 you might be able to do something similar with the Canon setup. It was discussed previously on the forum- if an RF 1.4x would work with the Canon RF-EF converter but unfortunately people tried and it doesn't work, apparently an extra tab on the RF 1.4x prevents mounting the Canon RF-EF adapter and the ID is too small for the 1.4x nose. If you were interested to experiment it might be possible to do something similar to the Sony setup with a Canon RF system, this link has some discussion, scroll to second last post and look at the video: So this setup would be RF 1.4x on camera then the modified third party RF-EF adapter then the Canon 8-15 Unfortunately this method requires taking a file to a third party RF-EF adapter but if you did that it might work with the RF 1.4x. Of course it is a gamble as you would not be able to return the adapter after filing if it doesn't work, so you would need to be prepared to take that risk, plus you are hoping the image is better to justify trying it out. I had a thought that maybe using a Canon EF 1.4x and an extension tube mounted to an RF-EF adpter might work, however I tried this on a CANON DSLR I have and a 25mm extension tube and it won't focus. It might work with a 12mm after market extension but it would be a gamble. In both the Canon and the Sony case the total spacing of the Metabones or RF-EF adapter plus the camera flange distance is equal to the Canon EF flange distance of 44mm which is likely why it can focus correctly. which makes me think the EF 1.4x option probably would not work. On the WACP-C vs WWL-1 vs WWL-C I seem to recall posts from people on SONY systems expressing the view that the WWL-1 and WACP were nearly equivalent with the same lens and depending on the lens the long end was not as good as the wide end. You could try reading through such posts. Here is an example discussion, where there is a discussion where the Sony 2x plus 8-15 and WACP-C are compared: If you take a pragmatic viewpoint the advantage of the WACP-C lies in flexibility perhaps more so than absolute image quality. The Canon 8-15 with SONY 2x is equivalent in quality to the WACP combo and with the SONY 1.4x is better in image quality than with the kenko 1.4x and also better than the WACP combination - at least on Sony with the 28-60 according to posts in the linked topic. The 8-15 is of course very sharp and bare will have the very best image quality, but lacks reach. Whether the lack of reach is an issue depends on what you are shooting and the reach may allow you to get better images if you needed to crop an 8-15 image.

For those wanting to see the news page including a video with Alex and Matthew discussing the strobe here is a link: https://www.retra-uwt.com/products/retra-maxi?srsltid=AfmBOorr_9G-QMUsgogETlI04k5pbBl880_aCycwoIofkEd05Yeksar6

Yes, but they can corrode and they lose tension over time, I would still try and source them if possible.

If you are going to the trouble, definitely replace the circlip as Dave suggests and also replace the springs. You need to lubricate everything as well, the o-rings need a little more grease than your main o-ring as I understand it as it is never replaced until the next service. There's not much in the way of guides on how to do this out there, though Ikelite has a video for their housings.

There have been various posts talking about the pros and cons of the various combinations of lenses and Nauticam wet optics as well as comparing performance of rectilinear lenses behind various domes. Few points you might consider: The recommended dome for the Canon 8-15 in Nauticam is the 140mm dome. Fisheyes are much less sensitive to dome size compared to rectilinear lenses and smaller dome sizes help with getting closer to take CFWA shots. You can even use the 100mm Zen dome with the 8-15, though corner quality might take a small hit. There is an extensive set of tests of various Canon optics in this post: It tests the Canon 24-50 behind the WWL and doesn't have good things to say about it. The Nikon 24-50/WWL-C combination is generally rated quite well, however the Canon 24-50 kit lens seems to be significantly poorer in optical quality. Now this is with the WWL-C, however I recall other posts stating there is not much to pick between the WWL and WACP-C with other lenses. Bear in mind too that the 24-50 needs to zoom into 28mm to remove vignetting with the WWL-1 - the WWL-C is designed for 24mm lenses. Rectilinear lenses generally require big domes, though some of the newer lenses that focus much closer work well with the 180mm dome. They lack the barrel distortion which enlarges the subject in the centre making fisheye images pop. On the subject of teleconverters with the Canon 8-15 you mention the Sony 1.4x/2x with the Canon 8-15, these work because they place the Metabones adapter between the teleconverter and the 8-15. Optical quality is better than using the Kenko 1.4x. It needs this order of assembly as the nose of the 1.4x fits inside the the empty spacer of the Metabones adapter. In this case the metabones acts like a 22mm spacer. In theory you could use the a RF 1.4x- Canon RF-EF -Canon 8-15, but the RF-EF won't work with an RF 1.4x. In theory again a Canon RF-EF-Canon EF 1.4x- aftermarket EF 12mm or 20mm extension tube- Canon 8-15 might work, but you'd need to test it. In general I would say the Canon 8-15 is an exceptionally sharp lens and very hard to beat behind a dome as fisheyes naturally work well behind domes and is a great solution if you don't need extra reach. The last point is that comparing diagonal field of view is a little misleading - you normally don't place subjects on the diagonal and fisheye lenses have the most stretching of the field in the corners. The WACP/WWL is like a zoomed in fisheye lens in terms of barrel distortion present. The horizontal field of a 180° (nominal) diagonal fisheye is about 144° while a WWL with 130° diagonal field has about a 106° horizontal field. The 8-15 is reported to achieve 175° diagonal field. This table compares horizontal and diagonal fields: Horizontal Diagonal Rect Equiv 15mm fisheye 141 175 4.5 15mm x 1.4 97 118 16 WACP at 28mm 106 130 13.5 WACP at 80mm 44.7 54 42 The Rectilinear equivalent is the focal length of a rectilinear lens with the same horizontal field. You can compare the field you would get from a Canon 8-15 with 14mm FF equivalent rectilinear here, it's on m43 sensor so the comparison is the 8-15 at 8mm and the 7-14 at 7mm. This is equivalent to the 8-15 at 15mm and 14mm rectilinear on full frame.

I recall you said that you had a steady red light which is the battery. If you lose the vacuum it's a blinking red light and it should go through yellow first . You can test this by pulling a vacuum and then immediately releasing it and observing what the lights do. It's always possible the valve has had it, if it uses a soft seat for example, that will eventually wear out. But to be sure about this see if the circuit does as described when releasing the vacuum as you would do if you wanted to open the housing. Another way to test if to see if you can fit your friends valve to see if it comes good with that. BTW the tool you showed is for the new model vacuum valve, you model without the press button uses a wrench with a little pin that fits in one of the holes on the valve. scroll down to the bottom of this link, above the pic of the pump: NauticamNauticam Vacuum Check and Leak Detection SystemNauticam is pleased to announce an exceptionally comprehensive vacuum system that allows the underwater photographer to confirm watertight integrity before entering the water. This system provides add If it doesn't do this as described, you have a different problem. A fresh battery not fixing it does not necessarily it's not a battery issue either, You might have bad battery contacts or the wire or switch has some issues with extra resistance or it could be a problem with the pressure sensor. A new valve/alarm system should certainly get you back in working order if that's the case.

apparently the vacuvin pumps for resealing wine work??

I notice that unhelpfully the SMC-1 is no longer in the port chart so you can't compare working distances any longer. Depth of field increase I'm not sure hoe they would increase this - it's generally proportional to magnification.

First suggestion is fresh battery. Though it should blink red/blue when switched if low. If you lose vacuum it signals this by flashing red not solid red. I found another reference online which indicates that solid red is dead battery. That's you best bet I think.

the port chart provides this information. My understanding was that the 1 and the 3 were very close in performance.

Depth of field is a function of magnification, if you reduce the magnification on the sensor you get more depth of field at constant f-stop. There are special cases with wet lenses but shouldn't apply to a simple diopter. Bearing in mind of course that the depth of field is already razor thin at less than 1mm with the bare lens at 1:1 magnification.

Yes, though it's surprising how little info there is on many species!

Welcome aboard Kip, good to have you here.

Same here, I have not had a housing serviced as yet, my Em-1 MkII was 6 years old and not serviced in that time, My local dealer said it was needed unless you had issues.

The MFO3 turns a 90 into a 50 and a 105 into a 60mm They report the Olympus lens becomes the equivalent of about a 35-37mm range of lens, which matches my experience.

This is my shot of a Rhinopias frondosa: https://www.aus-natural.com/Underwater/Diver%20Lodge%20Lembeh%20-Sulawesi/Lembeh%20Selects/slides/Weedy-Rhinopia.html The dorsal fin looks quite different to yours, though it is fading into shadow in teh shot, it looks like a regular dorsal fin rather tahn a series of flag like spines. It is showing the start of the spotty pattern they have though. Inaturalist thinks it might be an ambon scorpionfish, but I'm not sure,

Really nice Ben, fascinating creatures to watch

I have a copy of this book, I have been told there are some inaccuracies in it, I think from one of the Nudibranch ID facebok groups and also that a lot of species have changed names like all the Chromodoris sp. that are now Goniobranchis for example. I still use to get a starting point and cross check by googling the species name.