Chris Ross

yes, but apart from sunbursts, dynamic range I don't think is that useful under water, most shots I take I'm increasing contrast. Don't disagree there are certain situations where it will help. If you look at noise it seems to me the performance is closer than most people think. Here is one example comparing an EM-1 MkII with a Sony A7RV from DXO mark : You'll see the noise when the EM-1 is set to ISO200 is about the same as when the Sony is set ISO400. Effectively one stop better and shooting wide you may well want to have the Sony at 400 due to stopping down to f11-13, while the Olympus is happy at ISO200 at f8, but either way it's not a huge advantage. of course if you compare true ISO it's about a stop and half difference. The point is m43 can claw back quality by shooting at wider apertures and due to the smaller sensor they are less constrained by dome size. Here's a link to have a play with if you like: DXOMARKOlympus OM-D E-M1 Mark II vs Canon EOS R8 vs Sony A7R V |... The dynamic range curve is similar. In fact if you throw the Nikon Z8 or the Canon R8 into the pot they all very closely mimic the Sony curve. In fact DXO's most recent test results are from a camera released in 2023, it's like the curves are all so close there is little separate them and other shooting factors come into play like computational photography, AF, high frames/second etc. etc. to differentiate cameras today, making this sort of testing somewhat obsolete. Now I'm the first to admit these curves don't tell the whole story and certainly you shoot a bit higher ISO without noticeable penalty with full frame and there are other advantages for specific cases, but for general reef shooting and macro where you are shooting within a stop of base ISO it's close to a wash. I've linked in the past a shot taken on an OM-1 at ISO10,000 - it is surprisingly good. on the topic of large prints it seems to me we are talking A2 and above. If you look at physical prints in the big photo comps, I haven't looked lately but it seems they are mostly in A3 size range or the old 16x20.

Pure manual triggers I believe rely upon the X-sync contacts within the shutter closing the circuit between the centre pin and the common edge contact, so to work they need the shutter to operate. E-Shutter needs the trigger to talk to the flash and establish communications so the sensor can trigger the flash. So a pure manual trigger doesn't tell the camera flash is even connected - this for example is how the Nauticam manual trigger can sync at 1/400 with the OM-1, the camera doesn't lock out the higher shutter speeds and the flash still fires regardless. Electronic shutter needs to co-ordinate with the sensor reading to fire the flash at the right time to fully illuminate the frame - on most camaeras unless they have very fast readout this means the sync speed for electronic shutter is lower. Out of interest why do you want to use e-shutter? Seems like it would be simpler to take advantage of the high mechanical sync speed in most circumstances?

Digi direct, DCW, Camera Pro among others have bricks and mortar stores, Digi has 4 in greater Sydney. What town are you in? If you come to the Go diving show ingreater Sydney there's quite a few stores still that you can visit. Apparently OM system is an exhibitor at Go Diving.

You have to remember that while some of these testing and review websites might be useful, and well tell you various things about noise measurements and which combination has the best noise characteristics. They are however run by people who measure photographs rather than make photographs in many cases. the differences are often only visible when viewing the image at 100% on Photoshop and even then you need to look at them sideways multiple times to pick the differences. If you look at the images as a whole image it can be hard to pick the difference between well exposed images taken on m43 and full frame unless you are talking about extremely large images or very high ISO, but even then m43 can produce some amazing images in low light. You have to go down to a compact like a TG-7 with a tiny sensor and not expose it that well to produce an image that is obviously not as nice. Back in the day when digital first started there were big differences, these days things are much closer and gains are very much incremental. It's not that FF doesn't have it lace but for me and many others the gains aren't enough to offset the downsides of ownership.

Digi Direct used to be a go to, these days they sometimes don't have stuff in stock and don't always tell you till after you order. They used to be cheapest but not always these days. Avoid grey market importers - you often won't get warranty service locally as the warranty is through the retailer not the official importer. Digital camera warehouse is another to checkout, they have been around a long time. Another is Camera Pro. I've bought from Camera pro, digital camera warehouse and digi direct, sometimes Ted's George's or diamond have the model you are after at a good price. Best bet is to go to google and type in the model you want, then "price australia" and a bunch of options will pop up. you can look at online reviews but looking recently they all seem similar. Best to physically call them to check for stock prior to ordering.

Poked around on their site and the 10mm fisheye link is still up in Chinese. Change the site to English and it vanishes but I did find this: https://en.7artisans.com/shop.aspx?nid=2&typeid=68 Looks like they are offering a 7.5mm f3.5 APS-C MF fisheye to influencers to review. Reported to have a 205° field of view.

On the question APS-C and FF I would say that m43 is very close in performance to APS-C and for most people it's enough. The lenses offered in m43 are comprehensive between what OM and Panasonic offer, 3 macro focal lengths, native fisheyes a wide range of rectilinears, 4 or 5 lenses that work with WWL optics plus they readily take adapted lenses via Metabones. The ability to use the Canon 8-15 means you have a fisheye and at least in field coverage a rectilinear 14-28 equivalent in one lens, looking another way it's a Fisheye plus about 2/3 of the focal range of a WWL. The 8-15 gets to 28mm equivalent in reach while a WWL gets to 30-35mm depending on the lens used with it. You can't do this with FF Canon or Nikon, with Sony you can combine a Sony 2x with the 8-15 but it takes a slight quality hit which many find acceptable. Canon you can do it but involves taking a file to an after market RF-EF adapter. Other than that you are looking at very heavy and pricey fisheye conversion port.

N100 ports would be big enough to solve that problem and Isotta have solved it as they use 102mm ports for m43. Seriously though the N85 is a little limiting - it would be nice to load the Canon 8-15 from the back but not worth changing systems over completely. It seems to me that Nauticam could consolidate their port offerings by scratching the n85 ports and just offer N100 and N120, for one thing they could have every port in native size and not need adapters. For example the 140mm port and 4.33" comes in N120 and N85 but not N100.

I'm wondering if it worked better because you were shooting through more water and closer to shooting through the same amount of water as you were filming the guests. slates and fins unless someone else is holding them are at a relatively close fixed distance.

Is this tested in air or in water? As I understand it the diopter power increases in air compared to water, so the focus point comes in closer. That combined with increased spacing may be enough that it focuses inside the lens. If you have not tried it in water perhaps do that first? If it is still an issue are there any alternative ports you could try? For example the 5502 port for 60mm macro in combination with a 1"extension. Looking online it seems FL ports are discontinued so you would be looking for second hand ports.

I also get the standard option for uploading an image both for a new post and as a reply like this - Win 11 with Firefox: You could always try downloading Firefox to see if a different browser helps. Did you try just clicking the page where you want to paste and just using Ctrl- V?

You probably don't want to do that unless the reduction ring is shaped correctly to concentrate the rays. Reduction rings tighten the beam, but if light is reflected off a white surface it tends to diffuse it a bit which spreads the beam. The reflector looks like it tightens the beam significantly and is relatively tall, the taller it is the tighter the beam. You might not want it that tight for wide angle work. I know I left my reduction rings on shooting grey nurse sharks with a fisheye and it seemed to help quite a bit with backscatter. Also you are trying to recover light from the edge of the beam, looking at some data for the retra strobe at 120°beam angle the light falloff in this region is 5 f stops. Doing some measurements on my Strobe it looks like the reduction rings restrict you to about a 90-100° beam angle. At 90 degrees the the light fall off is about 2 stops compared to the center and at 100° it 3 fstops. What does that mean there is not that much light in the outer portion of the beam to recover with a reflective inside surface to the reduction ring. - but that light is enough still to illuminate very closeby backscatter, which the reduction rings block so stop it being illuminated. so the short version of that is it seems to me there's not enough light in this part of the beam to be worth trying to recover at least on my Retras.

Agree, just because using the wrong lube gives you a problem doesn't mean that silicone is bad for o-rings. A great many housings use Silicone o-rings including Nauticam, Marelux, Sea and Sea, INON strobes - any coloured o-ring is going to be silicone. On the topic of dynamic seals, this is not insert and twist or piston style o-rings where you screw a cap on it refers to parts that are always in motion or regularly in motion, one example might be the shutter lever on Nauticam housing where the shaft rotates to activate, but even that is not really that dynamic, dynamic o-rings examples of dynamic o-rings where silicone might be a problem include hydraulic and pneumatic actuators, pump shaft seals and even scuba regulators that use a piston. On INON o-rings the secret is sufficient lube. Housings it's a mere breath of lube just to get it shiny. On INON o-rings where you are screwing on the lid, I'm a bit more generous, you can feedl the difference once you apply enough.

Wondering how you conclude Silicone o-rings are one of the worst? The only downside you might consider is the low tear strength which they mention, but that is only an issue for dynamic seals - this might include anything that has a rotating shaft on a housing, but if it's lubricated prperly this won't cause an issue. EPDM is probably a better choice than Buna-N as it is more resistant to sunlight. Both EPDM and silicone seem like reasonable choices for o-rings in UW photo gear to me.

I've never seen the need at least with macro, at night you can use max sysnc speed as you are not trying to include any ambient light. For wide angle, if there's some ambient light, a low powered light helps, you usually don't need a bright focus light, mine is 700 lumens and I've used a 350 lumen light quite successfully, that low it's quite unlikely to show up unless your ISO is very high or very long shutter speed.