Chris Ross

The min focus distance for this lens is 170mm, given its dimensions and the size 0f the 140mm dome at 0.5x it will be focusing right on the dome, so I expect that the maximum practical magnification might be around 0.3x , so filling the frame with a 120mm long subject on the horizontal axis of the sensor. You could also consider a 1.4x to add to your 8-15 which would give you 21mm focal length, about the same field of view on the horizontal field as a 16mm rectilnear lens

You get vignetting at 8mm The 8-15 has a limit switch for APS_C so that it restricts you to 10-15mm. That way you don't end up with vignetting in the corners if you zoom past 10mm. It will have about the same angle of view as the Tokina 10-17 - something around 175° on the diagonal. For fields as you zoom, this table has calculated horizontal, vertical and diagonal fields of view along with the approximate equivalent rectilnear lens based upon the horizontal field. Horizontal APS-C horizontal vertical diagonal rectilinear Equiv Fisheye – 10mm 144 92 180 Fisheye – 11 mm 129 84 160 Fisheye – 12mm 117 76 144 11mm Fisheye 13mm 107 70 132 13.5mm Fisheye – 15mm 92 61 112 17.5mm Fisheye – 17mm 81 53 98 22mm

I found an online video where they explained about the bushing, sounds like it's hardened stainless steel, it can be replaced but needs to be drilled out., but it seems it only needs that is it's worn. I'd definitely try re-installing the knob and twisting and pulling if you haven't tried already. I would only tap it lightly trying to remove it, if you can rotate it it doesn't seem like it is seized. You might for example need to rotate it to a certain position before you can remove it.

I'm using the Nauticam N120 140mm port with the recommended 34.7mm N85-N120 and the 35mm extension ring.

I don't have direct experience, I don't recall many Seacam users among the forum members. It looks like they use an insert in the alloy of the housing for the shaft. It is possible that has a lip on it to prevent it pushing inwards? First thing I would try is replacing the outer knob and rotating while trying to pull it out. If that doesn't work I would try using a pin punch and gently tapping it to push it out from the inside. It may help to have the handle on the shaft on the outside so that you can rotate the handle a little in between taps or have someone rotate as you tap gently. If that doesn't work, try someone like Backscatter to see if they can assist.

The 10-17's main benefit is flexibility, sure you can get a bit better image quality, but the 8-15 is a much bigger lens. I suspect being a Canon mount lens it will work better on the EF-RF adapter compared to Sony-Canon metabones adapter. If you go with this setup you can always upgrade to Canon 8-15 with just an extension tube and zoom gear. It has a limit switch so that it zooms from 10-15 mm only for APS-C. As for the WWL, it is certainly versatile but it's not a fisheye, you would still want a fisheye of some sort if you are a wide angle person. You don't get the extreme central barrel distortion so much on the WWL compared to what you get with a fisheye. If you were using the Sigma 50mm previously. look at the Canon EF-S 60mm lens you would need to get one second hand, but it was extremely popular and should focus OK on an RF-EF adapter. When I upgraded recently I went with the OM-1 Very happy with that and I have the Canon 8-15 with Metabones adapter and it makes a very versatile wide angle solution it covers an 8mm fisheye plus the full range of a 7-14 lens so has more reach than the 10-17 does on APS-C. From what I have seen from test sites it's very close in image quality to the APS-C sensors.

Are you talking about more working distance or are you thinking a different shape to let light get on the subject more easily?

I haven't tried in such a small dome I have used the 7-14 a little in the 170mm Zen dome and it does OK at 7mm but corners are a little soft. I think though that using a 14mm full frame equivalent lens in a 100mm dome would be stretching the friendship quite a bit particularly as the 7-14mm doesn't focus ultra close. I recall seeing people complaining about the image quality in the Nauticam 6"dome back in the past on Wetpixel. I would be cautious about relying on written advice that lens xyz is fine behind dome abc unless there are sample pics to go with the post, people's definition of fine varies from "sharp at 100% in the far corner" to "I shot a shark and I can tell it's a shark and got lots of likes on my post"

Yes definitely, it will depend on what you are shooting, If you are in clear water in the tropics then a fisheye is definitely worth looking into.

It's still not a full fisheye, I seem to recall Alex Mustard saying a WWL/WACP wasn't a substitute for a fisheye. A 130 degree diagonal field sounds a lot but it's basically a very close focusing 14mm rectilinear lens with stretched corners as far as field coverage goes and doesn't have the extreme barrel distortion of the fisheye which brings the subject forward in the centre - the fisheye effect. For someone who does 80% wide angle as quoted by the OP. I'd suggest a fisheye lens would be important.

I think you are running into a problem with the basic physics. Diopters work by allowing the lens to focus closer, so if you want more magnification you lose working distance, yes there is some leeway to design lenses so that they achieve the same magnification with increased working distance, but I think in most cases this is a small improvement. Diopters are more powerful on long focal length lenses so another approach might be to use a different base lens or add a 1.4x to your RF 100mm. This would give you 2.3 x 1.4 = 3.2 x at the same working distance as your SMC-3. Another possibility might be to use the 180mm EF macro lens with the SMC-3. ON the port chart with the SMC-1 it achieves 3.6x and 63mm working distance. To use the RF-100 with a 1.4x you just need an extension tube the same dimension as the Canon 1.4x. You would of course have to research what impact this has on autofocus which will probably slow down a bit.

The SMC-3 has less power than both the CMC-1 and CMC-2, the data is in the port chart. I would consider the CMC-2 before the SMC-3 if you want something with a little less power as the CMC has slightly longer working distance.

The CMC-1 is more powerful compared to the SMC-1, the CMC-2 is similar in power to the SMC-1 with slightly more working distance. The Port chart for the RF-100 has magnifications and working distances for all the Nauticam diopters, the CMC-1 sits between the SMC-1 and SMC-2 in power: https://drive.google.com/file/d/1iTINzEby0S-7GndOhEjQZRP-CgyumZx3/view You can see that the CMC-2 has very similar magnification to the SMC-3 with very slightly more working distance. UNless you feel you need a little more power than the SMC-3 It doesn't seem like any of the Nauticam diopters offer anything in the way of improvement. The CMC-1 offers a little more power but almost in the same boat as the SMC-2 for working distance. What are you looking for? a bit more power than the SMC-1 or a bit less with more working distance? It does get hard to compare lenses from different manufacturers as they all use different methods to rate them and there are very few comparison tests between brands out there.

Sounds like you would really benefit from an accessory viewfinder on your housing, the new Nauticam viewfinders are designed for the bigger viewfinders on new mirrorless cameras and make a bigger difference UW than a newer viewfinders makes on land.

It's very hard to beat or match the Tokina 10-17, unfortunately the only way to truly match it on full frame is with the very expensive and heavy FCP. The WWL goes close but it's not a full fisheye with the effect that brings. You can adapt a Canon mount 10-17 to an R7 or Sony A6700. Nothing else goes close to this with the small dome size in full frame or APS-C. If you like small you could look at the OM-1 it's very close to the D500 in sensor performance, the lenses are tiny in comparison to full frame, the 60mm macro and the olympus fisheye are both excellent lenses, If you want flexibility you could use the Adapted Canon 8-15 which gives you the equivalent field of view of a full 180° fisheye through to a 28mm full frame equivalent rectilinear lens in one setup and it can be used behind a 4"dome.

Welcome, good to have you back!

I leave mine assembled. I did though remove all the screws and coat them with grease though, I figure that will help with making sure they don't seize.

Looks like a giant moray, if it is it should have a dark patch on the gill opening which seems to be behind the coral in this shot. DO you have other pics? There doesn't seem to be too many species which look similar to the giant moray you could point to as a maybe.

Some info here on PAL vs NTSC mostly seems to revolve around flicker under mains powered artificial light: https://www.reddit.com/r/videography/comments/s6j8cb/pal_vs_ntsc_for_internet_videos/ As for WB as I understand things colour grading has limited scope to correct colour casts and works best if you are close, unless you are shooting RAW video. In any case getting it right out of camera is probably a lot less work in processing and less likely to cause issues in the final clips.

Seems to be roughly double the energy input calculating the Ws for each full power flash the same way compared to the Retra flash ProMax. I seem to recall Retra used to quote a 130° coverage for the circular tube models, the maxi has 160° so won't be double the light on the subject. Changing the field covered from 130 to 160° decreases illuminance in lux( that is light intesity on the subject) by about 70%.

The logical suggestion is a WWL 1/1B however using a bayonet system with these lenses needs the nauticam bayonet-M67 adapter to fit on the AOI port - it doesn't fit on all ports if the rim is too thick. Seems like it would be better to use this with a 14-42 if mounting arrangements suited you. The WWL-C doesn't give full 130 deg with the 12-50 but you could use it with a Panasonic 12-32, but only way to mount this one is if the Nauticam bayonet adapter fits the AOI port. The AOI is an option as well you and have the choice of a PC or glass front dome and they sell a quick release setup as well as a buoyancy collar - it says the collar makes the PC dome +ve UW.

probably a good idea as long as they provide a decent area to charge everything.

It is established that the Nauticam manual flash trigger will sync at higher shutter speeds than the published sync speed. The key is that the strobe or trigger is triggered by the x-sync contacts which are basically an electro-mechanical switch incorporated into the shutter. There are no electronics that tell the camera that a flash is attached so the camera doesn't lock out the higher shutter speeds, it just flashes when the X-sync contacts close momentarily when the shutter is released. Whether the AOI trigger also allows higher shutter speeds depends upon the triggering circuit used - if the camera recognises it as a flash it will limit the camera to 1/250. It seems the EM-10 MkIV is a special case among Olympus cameras as it has a built in pop up flash and only that will sync at 1/250. Even hot shoe Olympus flash units that happily sync at 1/250 on other models like the EM-5 and EM-1 series will be limited to 1/200 on this model. It's only when you get to the higher end models that 1/250 sync is universal.

Interesting - it seems that the AOI trigger does properly support the RC mode based on what you have said. It would be so much easier if you could use the pop-up flash for triggering as it could do all 3 modes reasonably seamlessly at the cost of a little battery life - in manual setting the flash to 1/64 power triggers things reliably in my experience and uses very little battery power.

The thing with macro lenses behind flat ports is that the aberration increases continuously from center to edges as the angle the light rays are coming in gets progressively greater as the angle of view increases, so it's a progression, only in the very center of the port are the light rays perpendicular. However out at the rule of thirds points where you might place something important to your composition, the rays are at an angle and you are about half way out to the edge. If you photograph a test chart on land you will see something similar a slight degradation in quality that gets progressively worse towards the corners, but it is going to be hard to spot that in a regular photograph - It's only when the aberrations reach a certain level that they are obvious. UW the port and lens aberrations add together. The other thing that is claimed is reduced hunting - apparently due to compressed focal range. I would also think that removing flat port aberrations can only help focus is easier to find on a sharp lens. It sounds interesting for sure, But I think we might need to wait for some high resolution test shots to see if any improvements are enough to convince you that you need one! 😂