John E

Thanks for a great article and raising this topic. Also, Tim please do your article on neutral spaces. I took the attached photo this week which I personally really like because it did involve a some effort to try try to create a certain feeling and memory of the moment.

If you are willing to use APS-C mode when you need faster sync speed it is possible to get faster sync with the Sony A7R5 as that means the dark band at the top of the frame is not in frame. I haven't tested it thoroughly but tried it when I first got the camera and, from memory, I think 1/400s is fine. This is bearing in mind that the APS-C mode is 26MP and that the pixel size is the same as the Sony A6700 and larger than the OM System OM1.

Hi Chris, Are you now using your OM1-1 underwater? I know you previously had the OM-D EM 1 ii underwater and the Om-1 above. If so I am interested in your thoughts, maybe on a different thread. Thanks John

Thanks Chris and Phil. By the way Phil, in case anyone else looks for it, I found the review in issue #132. I'll try the Sony 20-70mm.

Thanks Chris, The Tamron 35mm has a close focus of 15cm. I can't see a slightly longer prime for Sony from them. I have wondered about the 20-70 and am tempted. I wonder how is does in an 8 inch dome? I see 9 inch is recommended. I am fussed about centre sharpness but not overly fussed about the extreme corners as this is mainly for photos with a central subject.

I am thinking more of close up coral colony and medium sized fish pictures that suit this focal length rather than pure macro. Just wondering what the conclusion is between the Sony 50mm macro and the adapted Canon 60mm macro on a late model Sony like A7Rv? Maybe a different prime is better like a close-focusing Tamron?

Obviously camera systems suit different people's use requirement so the title of this thread is silly. But the point that crop sensor lenses and suitability for reasonable size domes often work better for a particular person or underwater use is correct. That is not news, and all the advice I've seen given on this forum when people ask questions about new gear reflect that. Pooley hit it spot on when saying the photography is not about test graphs. Striving for technical perfection in a picture but not putting the same attention into creativity easily ends up with photos that are fairly boring other than a personal connection for the actual photographer. This is more true now than ever with the development of AI.

It doesn't look like you can assume you are getting the colour the diffuser claims when you take a picture underwater... Re Inon diffusers... From Driefish "The S-220 for example measure as 6650k without diffusers and 5400k with the Inon '4600k' filter." I am intrigued why the manufacturers may be off. Is there a reason or is it, say, the way the measurement is taken in water? I don't see any marketing logic for a manufacturer to incorrectly state a diffuser colour. The may not want their strobe to appear to customers as too high Kelvin, and that may be a trade-off for power, but if they make a range of diffusers why not be accurate?

Love the photos, thanks for sharing.

Thanks for the comparison photos, and for shining some light on this topic. Some replies have been illuminating. They do show the importance of smooth light fall off especially when using dual strobes angled slightly outwards to get even light across the picture Personally, I think the very colour-saturated coral reef photos, whilst beautiful, are quite unoriginal now and get too much exposure, whilst ambient light pictures that more closely reflect what we really see under water (and preferably capture some of the magic of it) are mostly left in the dark. Before I warm too much to making bad puns I will cool off and go and recharge.

Like Interceptor121 says, the TG-6 is hard to beat for snorkelling (but definitely use a housing as without one the camera will eventually leak at one of the little door seals). The 130 degree wet lenses are better than the 90 degree wet lenses which Mark said he didn't like. But if you are a very experienced photographer and you already have the cameras, and you are snorkelling, your situation is different to most. I suggest an important criteria is what field of view you want. The TG-6 with a 130 degrees wet lens that can come off to do great macro is unique. I also have the Ikelite TG-6 housing with small dome and the Olympus fisheye converter lens for the TG-6, which gives fisheye to macro in a tiny system. But if you want better image quality, and you have the cameras already, that similar zoom range comes with a weight and size penalty that potentially impacts snorkelling fun. If fisheye alone is ok the Olympus is better due to the lens options as it is compact, but you will possibly find that too limiting. Then if you want a narrower field of view you are looking at 8 inch dome ports or a wet lens. If you want zoomable fisheye then both cameras need adapted lenses and you are looking at similar sizes and quite expensive systems with adapters, zoom gears, extensions and housing manufacturers that support that option. Likewise, either system would be a similar size with a 130 degree wet lens. If the choice was Sony in Seafrogs versus Olympus in AOI, (or either in Ikelite) it really comes down to the lenses and how much bulk you want to swim with. And if that works out too much then it brings you back down a notch to the better compact systems with a wet lens, which is what I would be learning towards, pretty much just like the system Fruehaufsteher2 showed.

Have you thought about an AOI housing for the OM1? Maybe you would get more help from Backscatter.

One of the advantages of the Sony A7RV is versatility due to the sensor pixel density being like the A6700. With combined port extensions where 20mm can be removed, this means the rig can be used with the Kenko and a larger port for best full frame picture quality, but also handily can be used without the Kenko and with a small fisheye port and shorter port when minimum housing size is needed, such as when freediving. Then it can be used in full frame mode or the 26Mp APS-C frame size with zoom range. I am not sure if it better to use the APS-C mode on the camera or stay with full frame and just crop. Maybe someone can confirm? I don't think it makes any difference in picture quality but having the APS-C mode on the function button menu makes it very quick to switch to help framing composition.

So what is the real world interpretation? If one has the choice between Sony 26-60mm + WWL-1, the Canon 8-15mm, Sony 14mm or Sony 16-35mm at it's widest, and is taking the same type of shot such as a reef scene, which would be the better option for overall sharpness? Assuming the correct extensions are used and the appropriate dome size, is the fisheye the worst option unless the specific style is needed, or does the close working distance reducing the amount of water in front of the camera offset any drawbacks and mean it is the best option?

Maybe it is worth a test in a pool and have the same composition i.e backed off on the non-fisheye - this would better reflect real world use - as Chris H points out about the shooting distance for a given subject. For the Canon 8-15mm fisheye, if you are talking about an APS-C crop wouldn't it also be relevant to try it wider than 15mm? (noting the Sony A7Rv has the same pixel density as the A6700). i.e. I wonder what is the fisheye pictures edge difference between the APS-C crop at around 10mm (or whatever is the exact equivalent) to full frame at 15mm? Then there is the question of the view at the fisheye edge being so oblique anyway.

This is an example of using the Canon 8-15mm fisheye plus 1.4 Kenko with a Sony A7Rv but doing some partial de-fishing in Lightroom just because of the straight lines on the coral nursery. This happens to be with an 8 inch dome as that is what I had.

Olympus 7-14mm now sold Olympus 60mm now sold

I haven't used Weefine but have used AOI wet lenses. I have found the quality absolutely fine - but I now would avoid lower cost wet lenses that have a polycarbonate front element. Whereas it is possible to polish a dome port, to my knowledge the coatings on the polycarbonate front elements on wet lenses mean they can't really be polished, say if they get a scratch from a slight misjudgement when doing CFWA Getting a front element replaced then costs quite close to a replacement wet lens.

Housing now sold, camera and lenses still available.

I have for sale an Isotta housing + Olympus OM-D E-M1 Mark ii camera + some lenses. Other than the 12-40 mm lens, all items were bought new in 2022. Everything is in very good condition and fully functional. Comes with original boxes except for Olympus 12-40mm lens. Camera and lenses stored in a dehumidified cabinet. Camera only used in the housing. Items are in Queensland, Australia. Parcel post can be arranged. Isotta housing for Olympus OM-D E-M1 Mark II + Vivid Sentinel V5 plus manual pump (Asking AUD $1200) Olympus OM-D E-M1 Mark II body + Olympus FL-LM3 compact flash + 2 genuine batteries + Olympus charger (18,256 shutter count) (Asking AUD $700) Olympus 7-14mm f2.8 PRO lens (Asking AUD $850) Olympus 8mm f1.8 PRO Fisheye lens (Asking AUD $790) Olympus 12-40 f 2.8 PRO lens (Asking AUD $480) Isotta Olympus 7-14 zoom gear (Asking AUD $70)

I am a huge fan of the fish identification photographs of Gerald Allen, Roger Steen, Paul Humann and Ned DeLoach in books like Reef Fish Identification Tropical Pacific. I wonder if anyone knows what focal lengths they used. It strikes me that if you want longer reach MFT or APS-C is much more manageable and the amount of water you are shooting through is going to have a big impact on image quality and lighting anyway. (OM 90mm sounds appealing here) Another question is don't the 20-70 and 70-200 lenses extend a lot? Doesn't that effect image quality due to finding the best port extension length... eg difficult to get the right dome position on the 20-70 or vignetting at 70mm on the 70-200?

And you have to love the fish that need a fisheye lens. This reticulated whipray photo was taken on an EM 1ii with the Olympus 8mm.

I had (have) an EM1 ii i and now a Sony A7Rv. I just intended to sell the Olympus but have been hesitating. Both are really good but it is easy to underappreciate the Olympus. I have an Isotta housing and last year there was not a confirmation from them that they would make a housing for the OM1. (They do now.) I also wanted as high a resolution as possible as I am trying to take survey pictures of substrate and count coral recruitment. Hence my change to Sony. I can't see much benefit in the Sony in your circumstances except for the ability to crop, which could be significant. I am not sure about Nauticam but with the 102mm diameter port system on Olympus in Isotta I never have to remove a port to get the camera out of the housing even if using larger diameter lenses. I have found the 12-40 pro (thanks Chris Ross for the prompt) really good to use for medium size fish. I was using it with a flat port and extension that I had anyway and just the range from 40mm down to about 25 to 30mm. I assume it is considerably sharper than the 12-50. I was also using the 60mm macro. For me I really like versatility of the A7Rv (in APSC mode it has the same pixel pitch and resolution as the A6700). The autofocus is better but I didn't find it an issue on the EM 1ii. I tend to use back button and spot focus a lot as I am worried the focus will jump off my target. I've not found the AI on the Sony useful for fish so far. I have the 90mm and Canon 8-15mm fisheye and the Sony 28-60 which is probably not great for fish on its own (I have only tried it once - am waiting for a WWL-1 to arrive). I have not looked at the spec but assume the 28-60 has too long a minimum focus distance to be fun to use on its own. The viewfinder is very good. I have a 45 degree viewfinder on the EM 1 ii housing but haven't bothered using it yet on the Sony housing ( I very rarely use the LCD due to bright sunlight) The smaller and lighter lenses are something I miss when handling the camera on a boat. When I look back through my fish photos I can't tell by looking which ones are taken with the Olympus and which ones with the Sony. One thing about the Sony A7Rv is that, if I take a photo and it is not as sharp or detailed as I want, I now know it is is my fault and not the camera!

Thanks Whiskeyjack, I have the EM-1 ii. Interesting to know what Isotta recommended for you although the EM1 series and EM5 have different port charts (EM1 extensions being shorter) and the EM1 has the zoom cog is on the housing.

Hi Whiskeyjack, would you be able to provide the port extension length you use with the Canon fisheye lens Thanks. John