EMWL Critical Sharpness

Yes of course, a proper test is in order. I had a moment to do a pool test under controlled conditions. It's my fisheye at 130 compared to the EMWL with 130 lens. Same subject, almost the same exposure (f/11 vs f/16), 1/200 second, chose the sharpest of a set of 12).

Focus point is on the number 12 on the checklist, more or less the center of the printed checklist page. You can see that focus is correct on both, and there is text both in front and behind the focus point. There's also writing on the reg hose to compare.

Fullsize 48mpx images, uncropped, unedited, no sharpening applied.

Any ideas?

One more post for those who can't download the full-size jpegs above- two 100% crops, fisheye and EMWL.

18 hours ago, kiliii said:

Fullsize 48mpx images, uncropped, unedited, no sharpening applied.

Unfortunately, you cannot simply add full resolution photos to posts on this forum. The forum software has a size limit and downsizes them. You have to link to them via an external source or use a service like Dropbox.

As it is the full shots are too low resolution to say anything about, and the cropped versions don't provide the ability to inspect other areas of the frame and check for focus error.

Gotcha, thanks Isaac! Here's the dropbox link to the full-size files then.

https://www.dropbox.com/sh/dwi6b3tr3bajkzh/AABvtkxt0taJfx_AAP87Ck8ba?dl=0

Thanks @kiliii. From the full resolution shots it is clear that the EMWL shot has backfocus error. The image is sharpest around/behind the regulator. I'll also note that while shooting at f/16 will increase depth of field, it will decrease the sharpness of fine details a little bit compared to shooting around f/8-f/11. 

It would seem that the EMWL causes a backfocus error with your camera just like it does with my A7R II. The problem is that the image quality with the EMWL at f/2.8 is so poor that the camera's autofocus system fails to determine the correct plane of focus. The solution is to focus with the aperture stopped down some so the image quality improves enough for the autofocus system to work properly. The lenses I have tested needed to be stopped down to around f/5.6-f/6.3 to focus accurately.

So your next step is to try all the different autofocus modes/settings on your camera and see if there are any that will perform the autofocus operation with the aperture stopped down. It can be helpful to watch the aperture through the front of the lens with a headlamp while you try out different focus modes. I would recommend doing this with both the native and adapted lenses since they may behave differently. With my Sony I discovered that in AF-C mode after the initial focus acquisition it will stop down the aperture and continue to refine focus with the the aperture stopped down, providing me with a way to get accurate focus with the EMWL. I don't have much experience with Nikon mirrorless cameras and have no idea if there's a mode/setting that will accomplish this.

If you cannot find a way to autofocus with the aperture stopped down but still want to use the EMWL, then you could try focusing in front of subjects. With some practice you might be able to get a feel for how much in front of subjects to focus, but obviously this will never be an ideal solution.

Hi Isaac, thanks for looking at this and reminding me about all the original issues.

I had put out of my mind (aka repressed) all of this stuff for the last year as I have been on assignment and unable to use the EMWL, plus had to bite the bullet to buy a new lens, new port adapter and new focusing unit. Now I have double the lenses, double the focusing units, and double the port adapters and am no closer to a working EMWL.

As I have gone through all the original posts here, I am reminded that there is no real workaround that involves autofocus on Nikon. I am going to be knocking on Nauticam's door and seeing what they are going to do about their non-functional product now that an upset photographer from National Geographic is unable to use their used-car-lemon of a lens system.

What puzzles me the most is how it is that the focus shift aperture issue doesn't bother some of the shooters here. It obviously is messing with you and me, but everyone else seems to have it working on some level and that's very curious.

That's it for now! Cheers, Kiliii

No problem @kiliii. I looked back and refreshed my memory as well and realized I repeated a few things.

Please note that a lot of the earlier information is based on the false assumption that the issue is caused by focus shift, and among other things that explains why you switching to the 105mm F did not fix the issue. I'm not sure why Nauticam got that wrong, but it cost me quite a bit of time/money too since I bought lots of lenses trying to find one without focus shift only to discover that it wasn't even the issue. 

I am not necessarily convinced that there is no workaround for your camera. Have you fully explored the possible workarounds mentioned previously including using the setting that focuses at f/5.6 or using an AF fine tune correction?

The backfocus issue affects some camera bodies but not others, which is why the EMWL is unusable for some people but perfectly fine for others. So if you can't find a workaround for your Z7 then perhaps switching to a different camera body in the future is your best option if you want to continue using the EMWL?

2 hours ago, Isaac Szabo said:

Thanks @kiliii. From the full resolution shots it is clear that the EMWL shot has backfocus error. The image is sharpest around/behind the regulator. I'll also note that while shooting at f/16 will increase depth of field, it will decrease the sharpness of fine details a little bit compared to shooting around f/8-f/11. 

It would seem that the EMWL causes a backfocus error with your camera just like it does with my A7R II. The problem is that the image quality with the EMWL at f/2.8 is so poor that the camera's autofocus system fails to determine the correct plane of focus. The solution is to focus with the aperture stopped down some so the image quality improves enough for the autofocus system to work properly. The lenses I have tested needed to be stopped down to around f/5.6-f/6.3 to focus accurately.

So your next step is to try all the different autofocus modes/settings on your camera and see if there are any that will perform the autofocus operation with the aperture stopped down. It can be helpful to watch the aperture through the front of the lens with a headlamp while you try out different focus modes. I would recommend doing this with both the native and adapted lenses since they may behave differently. With my Sony I discovered that in AF-C mode after the initial focus acquisition it will stop down the aperture and continue to refine focus with the the aperture stopped down, providing me with a way to get accurate focus with the EMWL. I don't have much experience with Nikon mirrorless cameras and have no idea if there's a mode/setting that will accomplish this.

If you cannot find a way to autofocus with the aperture stopped down but still want to use the EMWL, then you could try focusing in front of subjects. With some practice you might be able to get a feel for how much in front of subjects to focus, but obviously this will never be an ideal solution.

If the problem is that the lens is unsharp at f2.8, then perhaps there is a different solution if the camera firmware gives you problems using AF when stopped down.  I'm wondering if placing a mask in front of the lens might help , effectively a filter ring with a 20-40 mm diameter hole.  It won't be as good as stopping down at the Iris and it may cause issues with vignetting that you would not get with the iris stopped down, but it should be fairly simple to try out?

22 hours ago, ChrisRoss said:

If the problem is that the lens is unsharp at f2.8, then perhaps there is a different solution if the camera firmware gives you problems using AF when stopped down.  I'm wondering if placing a mask in front of the lens might help , effectively a filter ring with a 20-40 mm diameter hole.  It won't be as good as stopping down at the Iris and it may cause issues with vignetting that you would not get with the iris stopped down, but it should be fairly simple to try out?

I like your thinking here, Chris. I've done lots of testing and did try this very thing. I 3D printed smaller diameter aperture holes and tried placing them at the front, middle, and rear of the EMWL and front and rear of the macro lens. Unfortunately, all they did was cause vignetting. They didn't improve image quality like stopping down the macro lens does.

However, the workaround I've currently settled on is very similar. I disassembled my macro lens and inserted a fixed aperture hole of around f/5.6 directly next to the stock aperture. in other words, I effectively reduced the max aperture of the lens from f/2.8 to f/5.6, and afterwards it focuses accurately with the EMWL. It's not without a few downsides since focusing in low light will suffer and I lose the option to shoot at large apertures, but it's the best solution I've come up with for my current system.

Ahhh, yes Isaac, I just went back and read the second page of posts as well- and it all makes sense. I still don't understand the problem on my end though- my Nikon Z7II and all the Nikon mirrorless cameras actually focus at the aperture they are set, until smaller than f/5.6, at which point the camera will focus at f/5.6. It just might be that Nikon custom function setting, 'show settings in live view', I will do a test tomorrow to see if that fixes anything.  

2 hours ago, kiliii said:

Ahhh, yes Isaac, I just went back and read the second page of posts as well- and it all makes sense. I still don't understand the problem on my end though- my Nikon Z7II and all the Nikon mirrorless cameras actually focus at the aperture they are set, until smaller than f/5.6, at which point the camera will focus at f/5.6. It just might be that Nikon custom function setting, 'show settings in live view', I will do a test tomorrow to see if that fixes anything.  

Well some of the lenses I tested wouldn't focus accurately at f/5.6 and needed to be stopped down a tad more for accurate focus (it was f/6.3 for several including the Sony 90mm). But are you sure your camera has been focusing stopped down? Have you watched the behavior of the aperture by looking into the front of the lens? If it is in fact focusing with the aperture stopped down to f/5.6 but still backfocusing then I would recommend trying an AF fine tune correction. 

6 hours ago, Isaac Szabo said:

I like your thinking here, Chris. I've done lots of testing and did try this very thing. I 3D printed smaller diameter aperture holes and tried placing them at the front, middle, and end of the EMWL and front of the macro lens. Unfortunately, all they did was cause vignetting. They didn't improve image quality like stopping down the macro lens does.

However, the workaround I've currently settled on is very similar. I disassembled my macro lens and inserted a fixed aperture hole of around f/5.6 directly next to the stock aperture. in other words, I effectively reduced the max aperture of the lens from f/2.8 to f/5.6, and afterward it focuses accurately with the EMWL. It's not without a few downsides since focusing in low light will suffer and I lose the option to shoot at large apertures, but it's the best solution I've come up with for my current system.

I was wondering if the vignetting would be a problem. Your solution certainly sounds good, though not everyone would be keen to perform such surgery on their lens.  It might be something Nauticam could explore if it was possible to add a stop somewhere within the lens system.

15 hours ago, ChrisRoss said:

I was wondering if the vignetting would be a problem. Your solution certainly sounds good, though not everyone would be keen to perform such surgery on their lens.  It might be something Nauticam could explore if it was possible to add a stop somewhere within the lens system.

Yes I realize most people aren’t comfortable disassembling lenses, which is why I haven’t recommended it as a solution for others. But with the Nikon 105mm F that kiliii is using it might be possible to simply stick something in the aperture lever slot to prevent it from being able to open all the way. However I’m not sure if this would cause any issues as I don’t have a Nikon body with me at the moment to try it out.

I agree, perhaps if Nauticam placed a smaller aperture in the correct optical position within one of the EMWL components it might fix the issue, though obviously at the expense of less light making it through.

Another possible solution that I haven’t mentioned yet is to use a different lens with a smaller max aperture. I tested the Sony 28-60mm and 28-70mm lenses for this reason. Both have a max aperture of f/5.6 at the long end, and both did focus accurately with the EMWL. There was too much vignetting with the 28-60mm, but the 28-70mm was quite good with only a little vignetting. I think they both required a thin extension tube to get them to focus close enough though.

Hello all,

I did a ton more testing in the pool here today and was both surprised and frustrated.

For my setup the macro lens does autofocus at 5.6 when set between 5.6 and 32. And indeed the quality at 5.6 is pretty bad so I can certainly see why AF could have a problem.

Nonetheless with the EMWL the focus is consistently behind the focus point, at all apertures and using all focus zone types on my Nikon Z7II. If I use AF-fine tune at -20, I can get the focus to be correct, but unfortunately this is distance dependent. What fine tune setting works up close doesn't work once the focus is on a subject further away. So that is not a viable solution either.

I could possibly restrict the movement of the aperture lever on the macro lens to force it to focus at f/8 perhaps, but given that the focus is consistent (and thus behind) in my high-contrast focus testing, I don't think that it would help. 

It's weird that my EMWL doesn't work on my buddy's Canon R5 with 100mm in Nauticam housing either. He is having the exact same issue (different focusing unit). His shots appear heavily back focused as well.

I'm really sorry to hear that nothing you've tried has fixed the issue. I know it's very frustrating.

With my Sony most of the lenses I tested still had the backfocus issue when focusing at f/5.6 and needed to be stopped down a tad more for accurate focus. So it's not too surprising to me that your setup is backfocusing at f/5.6.

That's too bad that the proper amount of AF fine tune correction is distance dependent. That would seem to disqualify that as a solution. 

I'm not sure I'm following why you are discounting restricting the aperture lever without trying it? Finding a way to restrict the aperture fixes the issue on my setup.

It's unfortunate but good to know that the Canon R5 also has the backfocus issue. If that's the case then mirrorless cameras from Canon, Nikon, and Sony can all be affected by it, while Nikon DSLRs and newer Sony mirrorless in AF-C mode seemingly aren't. I haven't heard reports one way or the other about some of the other brands.

I find it honestly unacceptable that this apparently wasn't properly tested before it went into any port chart. People are paying serious money on this setup (and others) and having to guess and pray whether your particular setup will work, while having pretty much no way to return gear after testing and finding out it doesn't work as advertised is really bad.

On 3/7/2023 at 6:35 PM, kiliii said:

Hello all,

I did a ton more testing in the pool here today and was both surprised and frustrated.

For my setup the macro lens does autofocus at 5.6 when set between 5.6 and 32. And indeed the quality at 5.6 is pretty bad so I can certainly see why AF could have a problem.

Nonetheless with the EMWL the focus is consistently behind the focus point, at all apertures and using all focus zone types on my Nikon Z7II. If I use AF-fine tune at -20, I can get the focus to be correct, but unfortunately this is distance dependent. What fine tune setting works up close doesn't work once the focus is on a subject further away. So that is not a viable solution either.

I could possibly restrict the movement of the aperture lever on the macro lens to force it to focus at f/8 perhaps, but given that the focus is consistent (and thus behind) in my high-contrast focus testing, I don't think that it would help. 

It's weird that my EMWL doesn't work on my buddy's Canon R5 with 100mm in Nauticam housing either. He is having the exact same issue (different focusing unit). His shots appear heavily back focused as well.

Hello, I had been searching for someone using an R5 to comment on results, actually have R5 with EF100.  After reading the thread, is is scary expensive for less than excellent or good results, not the usual for Nauticam, I have been eager to purchase EMWL, however, seems should put the breaks on.

On 3/9/2023 at 12:17 AM, hyp said:

I find it honestly unacceptable that this apparently wasn't properly tested before it went into any port chart. People are paying serious money on this setup (and others) and having to guess and pray whether your particular setup will work, while having pretty much no way to return gear after testing and finding out it doesn't work as advertised is really bad.

Is concerning to be sure...

It is really unfortunate, because the system really has so much promise and can do a lot if it does work. Alas for now I don't see any good ways around the focus issues with Nikon or Canon mirrorless at the moment, as the problem seems to be strange quirks of how mirrorless cameras autofocus. I can't say I have any idea why Sony mirrorless seems to work, but the latest generation of them does appear to be just fine. 

I finally just threw in the towel and talked to Backscatter- they took the entire system back for store credit, (a gigantic impressive statement about their customer service). They have had other customers also having the same difficulties, and I'm sure their input will guide Nauticam. Nauticam should at the very least properly list technical specifications of cameras that do and do not work- because right now all the new cameras other than Sony are non-autofocus with the EMWL. 

On 3/22/2023 at 4:38 PM, kiliii said:

I can't say I have any idea why Sony mirrorless seems to work, but the latest generation of them does appear to be just fine. 

I finally just threw in the towel and talked to Backscatter- they took the entire system back for store credit, (a gigantic impressive statement about their customer service).  

The newer Sony I tested (A7R IV) still had the backfocus issue in AF-S mode but worked great it AF-C mode. That's because it focuses wide open in AF-S mode but focuses with the aperture stopped down to f/8 in AF-C mode. I presume even newer bodies behave similarly since Alex has reported accurate focus with the EMWL with the A7R V in AF-C mode.

I'm glad they at least took it back for store credit. 

I just returned from a two week trip on which I shot the EMWL extensively, and now that I finally got my setup working well I really enjoy shooting with it.