dentrock

I use Sony C-AF (with tracking) all the time underwater, and mostly BBF. I could be mistaken, but I sense that BBF makes it quicker to acquire focus in tricky situations. On land I rarely use BBF, because the Sony ergs are not so good for that. In the end, it's whatever maximises your keepers.

I used to be a half press guy, but now I've joined the dark side with BBF, since Nauticam ergs are very good for BBF. But I haven't disabled AF with shutter, so it's there if I need it.

Well it does. But depends a bit on the skill of the photographer I suppose. But don't take my word - check out Alex Mustard's clip on "Curved Ports". He is quite a fan of the Sony 50 macro - especially behind a dome - as am I.

Sorry, I meant a shorter ext of course, to position the lens further into the dome... Compromise reached was 45mm total inc adapter (no shade). At 35mm, shade vignetted, but not the dome. At 55mm, dome vignetted badly (no shade) - not water tested. It is possible that in addition to fixed aperture, you might get away with fixed focus (at f11), provided you aren't trying to do CFWA... I also tested this lens with the 8.5" dome, but vignetting is worse, as expected, since the OC is approx 25mm behind the port flange. I won't be buying the AF version until / unless others can show it works well without vignetting, on FF. The Laowa 8-15 AF is still on the cards, so hopefully it won't be quite as wide FOV as this 7 Artisans. Over to you, Phil, if you are getting one!

I bought the manual version of this lens for E mount recently for under AUD 400. It arrived with very faint distance and aperture markings on the lens, and without the advertised glow in the dark ability. I would have returned it except optically it seems quite good. However after experimenting with it underwater, I'm not convinced manual is worth the trouble (for underwater), partly because the zoom gear I cobbled up was a Nauticam N120 size, which meant the lens has to be removed first, to remove the camera from the housing. You also have to recalibrate the focus scale, which requires a bit of careful maths, and the result is hard to read underwater. So an AF version is welcome... except for one potential problem: The manual version is 185 degrees diagonal. I could not exactly align the lens' EP with the optical centre for the Nauticam 140 dome, without vignetting caused by the dome itself, and that's with the shade removed. So I couldn't improve on an approx 30mm diameter circle centre sharpness at f11, and that's with a small amount of the vignetting. A longer extension to remove the vignetting reduced the sharp centre circle to just under 24mm, which is not great. So be prepared to crop if the AF version is also 185 degrees...

Since its been covered extensively in the links above and various threads, no need to repeat the process description. Probably quickest to spell out the particular lens / camera / housing / dome combo you are interested in, and ask if anyone is using / can advise on how it goes. There are many possible 'off piste' (off port chart) rigs, some of which work very well... and some which don't!

It is not a full hemisphere. The optical centre for the 140 is approx 7mm behind the mounting flange. I understand the only full hemisphere ports you can buy are custom jobs.

Not sure if your interest in the (presumably Nauticam) 230 dome was for the 16-25, but I found that lens works well even with the small 140 dome (radius 70mm), and not much further improvement with the 180 dome (radius 110mm). I used 25 adapter + 35 ext with the 140. Central area of sharpness when viewed at 100% was between 24 and 36mm diameter at f11. So if you are OK with f11 and this FOV range, it's a good compact rig. The Nauticam zoom ring for the 24-50 fits this lens, since they are made as a complementary pair. I'm not aware of a version "II" for this lens, so if it exists, disregard this post.

I reckon it's worth your trying to pick up a used old-style 20mm N120 extension. There are now at least 2 different styles for the N120 extensions, with the latest one super expensive as Chris says. But you should be able to buy the older one for $100-150 used. Look in the classifieds or place a WTB ad. Also, be warned: you are about to go down the rabbit hole of Nauticam accessories! I have acquired a massive collection over the years and can now at least test almost any lens combo. Re the compact port base stuff: yes it's old school flat port combos (I have some). I used to use it for different macro lenses, before I changed to domes for those. I don't think they ever made a screw thread dome to suit. Most likely they discontinued the screw thread experiment because threads can get very difficult to dismantle unless you carefully maintain them. Pre-digital Aquatica ports had the same issue - you needed a pair of strap wrenches in your kit!

I only happened on this topic out of boredom! I had a Nikon F90X and Subal housing, in prehistoric times. Both long gone, BUT.... I kept the viewfinder as pictured above! It screws into the camera eyepiece. I think I kept it because I got such a lousy price for the housing. Perhaps it's even my housing you have. Can't be many of them about in Oz. So, given that you seem to be in Australia I could probably be persuaded to sell it, so message me with an offer by all means. Btw, the housing performed quite well. The main problem was forgetting to nip up the locking screws with the supplied wrench, as I used to store it with the screws slackened off. I suffered one flood as a result, plus a couple of near misses.

Then I suggest you also go for it underwater. I'm the opposite - I prefer A7CR over A7RV for topside and underwater. I ran them side by side in Nauticam housings for a couple of years, and ended up selling the housing for the A7RV. Body + housing is 1.1kg heavier.

OK, thanks. Look forward to your AF update on the Tamron in due course. Regarding sharpness right across the frame with the Sony 100, I can't give you a clear answer, even though I went back to the original uncropped raws just now. My priority was the AF, and I assumed the sharpness question would fall into place. But because the AF target jumped away from what I intended, my sharpness reference point (always an eye, if there is one) is no longer accurate. So I have to look for what appears to be the sharpest point in the image and compare that with the far corners. And even then, perhaps the AF had not been properly acquired, so there may be no useful comparison. Best I can say at the moment is 'OK' into the corners (i.e. better than a flat port), but overall sharpness doesn't jump out like it does with the Sony 50 and 140 dome. I hope that changes if I get the AF sorted! At least I got some keepers, which is more than I can say I got with the 90 macro and MFO-1. I have just acquired a Nauticam 37122 4" WA port (as per Alex Mustard 'curved port' video quoted on another thread). I struggled a bit developing specs for it (Nauticam didn't bother to answer my query about the radius), but have firmed up on an estimate of 110mm outside dome radius, which makes sense as it would be the same as the 180 dome and possibly the 8.5" dome. But applying this radius to the port length suggests that Alex using a 16mm extension with that port and 50 macro means it is still quite a long way mis-aligned (my estimates suggest 45mm extension for the 50 macro with this port). Although he also said a longer extension was better for optimal sharpness, without saying how long! Anyway I have ordered 30 and 40 extensions which I think should cover the 50, 100 and also part of the 20-70 range (from about 40-70), using the 37122. OK, the 20-70 isn't macro, but it does a remarkable job with AF and close-up, so is good for moving fish. I will test everything AF with the 100 before giving up, as the combo would suit me perfectly if I can get it to perform.

Isaac, Just to confirm your thoughts on the Tamron 90 macro with your dome: have you noticed any negative results with AF, in particular AFC? And is it the latest version with VXD focus motor? I'm determined to keep testing the Sony 100 with a dome and AFC, but if I can't get it to perform as well (or better) than the Sony 50 macro with dome, passing the Sony 100 to my wife for spiders and getting a Tamron for underwater might be an option. Thanks

Small point which probably no-one will agree with: The PZ 10-20 is a great lens. If you move from Sony APS-C to FF as I did, there's nothing as compact as the 10-20 available in FF. I'm regretting selling my 10-20 instead of keeping it for use in crop mode with my A7CR (or even disable crop and get a bit more FOV out of it; e.g. square format). I found the button zooming a bit clunky though, and would probably go for the zoom gear instead.

Well, best to try it and see what you think. My estimates suggest using the 35.5mm adapter with 140 dome and 50 macro would put the dome approx 11mm too far forward. You will likely lose a little close-up range. I have both adapters. I never tested this combo with the 35.5mm. The 25mm one was hideously expensive when i bought it, but seems to have come down significantly in price (unique for Nauticam!)