Chris Ross

To start with you'll need the 34.7mm N85-N120 adapter that's now discontinued I believe, then a lot of extension. Being 20mm equivalent, the 180mm dome is probably fine. It's heavier (690gr) than my Canon 8-15 which requires about 1800 gr of buoyancy to get near neutral with my setup. I think stick to the 8-18 or the OM 8-25mm 😂.

If that is its lure, it looks very odd, the lure is one key ID feature to compare. You could try posting on inaturalist and also have a look at fishbase and browse through the images there. https://fishbase.se/identification/SpeciesList.php?class=&order=&famcode=192&genus=&areacode=&c_code=360&depth=&spines=&fins=&TL=&BD=&resultPage=1&sortby=species or try posting in this Facebook group: https://www.facebook.com/groups/frogfishlovers

Yes that's the idea, but don't assume your USB plug will pass through, you would need to test it! Originally developed for electric sync cables. I know Nauticam needed to make a new adapter to get the the right-angle USB plug to pass through their M24-M16 adapter.

Welcome to the forum, hope you enjoy it and find it useful.

Thanks for the clarification Phil, I recall people saying the FCP had noticeably small depth of field.

Hi Phil, one thing to note is that in reality the WWL is not equivalent to a 10mm rectilinear. They both have a 130° Diagonal field of view, but the horizontal field with WWL/WACP is about that of a 14mm rectilinear lens which has a 104° horizontal field while the 10 mm Laowa has a 121° horizontal field. This is due to the barrel distortion stretching the corners. So the correct lens to compare it to is a 14mm rectilinear behind a dome. The 14mm has more magnification and so less DOF. Would you say that the WWL still has less DOF than a 14mm rectilinear behind a dome?

Have a look at the table they are comparing 4 different lenses to the 28-60 and saying the 28-70 is not as good as the 28-60. Copyright © 2025 WaterPixels. All Rights Reserved Powered by Invision Community

The post I linked discusses the 28-70 briefly here and in the table above it:

It's not going to be first vs second curtain sync, that just moves the timing of the pulse from the beginning to the end of the exposure. I don't know of any explanation apart from shooting at higher than the maximum sync speed. Shooting macro you would notice any other issues like dark background water as the exposure is entirely from the strobe. Look at the EXIF data in your original files, what ever you use to process the images will report the shutter speed used. More than likely you could review the images in camera and get it to report the aperture/shutter/ISO used.

This is clearly something else, on minimum power they should allow for rapid firing, something is preventing this. The suggestions I posted above are test for potential issues. My first inclination is a problem with the trigger, online I see various issues reported with the Z8 and trying to sync with manual flashes.

It's been discussed here and also I think on old Wetpixel forum, here's one link I found: There are probably other posts as well.

It seems like you might be reaching the natural limit for your batteries if this is the case, potentially it's not so much the exposures taken but the time the camera is on, presumably it doesn't go off to sleep at any point in the 4-6 hours. I also see Canon has a new battery out the LP-E6P, this video claims greater run time for a cinema camera using it: Totally Awesome - Canon - What Have You Done - LP-E6P vs...I just watched a great video on youtube by Josh Sattin. In it he compares video runtime performance between the new LP-E6P and the now older LP-E6NH. Since I shoot in 4K 24p most often, this was hug Might be worthwhile getting one of these to try it out and see if you get an improvement?

There's something going on there, at minimum power it should fire off a few bursts before needing to recharge, regardless of aperture you are using. The aperture is a separate problem as it won't burst on min power . A couple of things to try: Try progressively reducing frames/sec See if the camera will allow setting second curtain sync, then do a test shot in a darkened room with the shutter speed around 1 second. This is a handy way to check if a pre-flash is firing, the pre-flash fires first and the main flash at the end of the exposure. It just allows you to see both pulses. I know it "shouldn't" but worth checking. What batteries are you using - eneloop or eneloop pro is generally recommended. How old is your flash trigger - it may have some issues with the Z8 as it has no mechanical shutter?? Try triggering you strobes with a Nikon speedlight as trigger if you have one, test shooting into a mirror so you can see if the strobe fired easily If you still have your OM-1 see if burst shooting works there

Need more details of what you are doing, what trigger, manual or TTL, are you using the booster, how many frames/sec you are trying etc?

Thanks for the update on the strobes, I also upgraded recently, however I got a set of Retra Pures before they were discontinued, which were lower powered but significantly cheaper. The biggest change I noticed was significantly less backscatter when using them with reduction rings for macro shots. By no means backscatter proof but immediately noticable compared to my old INON Z240s. Haven't done much wide angle with them as yet, but been pleased with light quality on what I've done so far.

So is this only when you started using it in very cold water or is it was working for a while in the very cold water but suddenly started dying? This may indicate a new battery could do better? Other than that you could try keeping the housing in a cooler with a hot water bottle until you hop in the river perhaps?

Your best bet is probably the newer battery, it could be you've lost a bit of capacity of your existing battery as well if it's a few years old. The USB bulkhead only helps if the camera allows battery charging in the camera, the 5D MkIV does have this option it seems?

I found a reference that states that a dome port gives increased depth of field in water compared to what you would get from the same lens in air. This is due to the object being compressed into a virtual image close to the dome. Whether the Ivanoff optics work from a virtual image I don't know, but I expect that it quite possibly could. They give an example of a 24mm lens at f8 imaging an object at 1m distance having 563mm DOF UW and 424mm in air. Here is the reference, scroll down to section 4. https://pmc.ncbi.nlm.nih.gov/articles/PMC4732081/ Without doing a detailed analysis, it's basically guesswork as to what is going on as the Ivanoff optic is neither a dome or a flat port. A flat port is limited to a field of 96° by Snell's law, but a 16mm lens has a field of view of about 106°. Odd things can happen with some optics UW, the Nauticam FCP for example seems to suffer from reduced depth of field based upon posts from users when it was first introduced.

Welcome aboard, I recall we have a few free diving photographers on the site. Type freediving into the search box and it brings up a lot of posts.

Not on a APS-C camera but I reported on using it with the Olympus 60mm macro (2x crop) recently: If it works well on m43 and full frame it stands to reason that it will work fine on APS-C. The 100 mm macro is 160 mm equivalent on the R7 while the 60mm macro on m43 is 120mm equivalent, so I would suggest even more of a case to use it on APS-C. The specs for the field of view and working distance /magnification on Canon APS-C is on the MFO-3 port chart: Google DocsMFO-3 2025-08-27.pdf

Great images captured must have been quite the experience.

I have no doubt it would work well in a dome, I would say though using it as macro lens is different to use in a dome where you are out in the 0.3x magnification and less with a working distance up near 70mm due to the dome where the AF of macro lenses generally picks up. I know what you mean about focusing on skinny things - transparent things give similar problems, seems like there are some things that the AF gets confused with. I encounter occasional things the AF doesn't play well with on my m43 setup.

I have the original Nauticam 45° which I used with the EM-1 MkII before moving it to my OM-1. The attachment is different between the MIL and DSLR versions, but the mounting can be swapped over to suit either a mirrorless or DSLR housing. As I recall the corners of the viewfinder were a little soft in the EM-1 MkII, while in the OM-1 they are softer still. The centre of the image is fine but reading to info in the corners is a little harder. The new versions are reported to be better in the corners. this approximates the view through the 45° on the OM-1 , ignore the vignetting as that's due to alignment issues with the lens and viewfinders. The blur in the corners is halfway between the far left and right side of the info bar at the bottom of the viewfinder image. It's difficult to get everything lined up using a camera lens compared to just placing your at the viewfinder. The EM-1 MkII viewfinder view is a bit better than this but the corners are still a little blurry.

The acrylic dome would probably be easier for splits as it is floaty compared to the glass, but using UW, it will want to try to twist up. Of course it is more prone to scratches.

Yes macro is easier without a wet lens. The system only focuses in quite a narrow range with the diopter. The 50mm has a different issue in that it 1:1 magnification where it covers 36 x 24mm is achieved at about 10-15mm from the port making it difficult to use and lighting is difficult, in practice it probably only easily achieves the sort of magnification you currently get with your current setup. What I was trying to say with ikelite is they will allow you use your lenses UW and will work, but there are various compromises. They have limited flat ports available for example they offer the same port for the 3 different macro lenses in m43 which are different lengths which means the shorter lenses are set back behind the port. What this means is that closest focus for those lenses is inside the port meaning it restricts the magnification you can achieve. They don't tell you this though. you also need to look at the fine print for each lens in the port chart to see if there are any restrictions. In particular for the DLM system there are many port options that won't allow zoom, they rely upon a 6" port with a zoom knob as there is no zoom control on the housing. They also don't have a 4" dome for a fisheye lens. Don't get me wrong amny people use their housings, but there are more compromises. On wet lenses, they rely on having a well fitted flat port and if the front element is too far back in the port you get vignetting. the lens in question might work behind the port by itself just fine but will vignette in combination with the wet lens. The other consideration with Ikelite is that it is only setup for wired triggering, which means maintaining the o-rings on trigger cables. Something I'd prefer not to do, The website only mentions using a manual flash bulkhead. You might be able to use the UWT external flash trigger to trigger with fibre optics. If you are determined to go with the A7CII maybe consider the new AOI housing, has built in vacuum and flash trigger with Sony TTL support or manual. based 100% around the Sony 28-60 it seems. You would use it like the RX-100 and rely on wet macro and wide lenses. You could use the +10 diopter you have and possibly buy one of the AOI wet wide lenses.