Some results from Red Sea, primarily Nikon 14-30 + S&S correction lens

Hi! I recall some of you being interested in images taken with the Nikon Z 14-30/4 used with the Sea & Sea 82 mm correction lens. I just came back from a trip to the Red Sea where I just this combination behind a 230 mm Zen dome. At least to start with, here are two images. Both are uncropped at 14 mm, ie as wide as it goes.

The first one is at f/8:

And the second at f/5.6:

I'm aware these are very wide apertures but OTOH that makes it more interesting. Given the apertures and the short focal length - notably wider than the common 16 mm - I'm happy with the results.

Thanks! I hope the trip was fun.

With the S&S correction lens and a 230 dome, I guess the set up is about as good as it could be. Are the corners of the images sharp at the apertures you used?  You can't really tell from these image sizes.

12 minutes ago, TimG said:

Thanks! I hope the trip was fun.

With the S&S correction lens and a 230 dome, I guess the set up is about as good as it could be. Are the corners of the images sharp at the apertures you used?  You can't really tell from these image sizes.

 

I know, I tried to upload larger images but ran into size limitations. Of course I could upload crops of the corners, but not right now.

At these apertures - no, the corners are not sharp. There is visible smearing. But, IMHO, not that bad smearing and it stops a quire small way into the image. A crop corresponding to, say, 16 mm shouldn't show much smearing even at these apertures.

I can see, also later, if I can find some pictures taken at slightly longer focal length.

2 minutes ago, horvendile said:

At these apertures - no, the corners are not sharp. There is visible smearing.

Thanks! Yeah, I thought there was a little smearing in the corners.

If you have time later to upload a few more crops, I'm sure folks would be interested.

Longer pause here than I expected, but here goes. First, a zoomed crop of the first image. From a pretty central region out to corner. You can match it with the original image above. My take: yes there is noticeable degradation, but still not bad. I mean, consider full frame, focal length and aperture.

Next up is this picture at 16 mm and f/11, a more common setting. This crop shows the entire short side and upper corners of the sensor in portrait orientation. Focus is - I would assume - on the diver at the bottom of the crop. If you think it's too hard to see I can do some more crops of this picture.

On another note, to my surprise I used the Nikon 8-15 fisheye very little on the trip. But my limited findings on using it with Sea&Sea housing are:

[NOTE: I got things backwards in my head when writing about extensions in the following paragraph. ChrisRoss points it out further down in the thread and I stand corrected.]

The lens chart recommends using no extension at all with the S&S 230 mm dome port. I tried this for the Zen 230 mm dome port; this configuration worked fine with the Sigma 15 mm fisheye. However, at 15 mm the Nikon shows the dome shade in the extreme corners. While the shade can be removed I don't want to do that, I just know I'll scrape the glass on some rocks. The only extension I had was 40 mm and using that the front of the lens ends up quite close to the glass in the dome port. I didn't like the look of that but never actually tried it in the water.

My idea is to get a 20 mm extension ring. Should be ok. Of course, cropping the images slightly is a cheaper option. With the Z7 I have a lot of pixels but yes I will lose field of view if I crop.

Edit: adding non-cropped image.

Thanks for those. Good to see and to know the Z 14-30 works pretty well.

On the Nikkor 8-15mm, I use a 20mm EFR with an 8" dome. Works a treat.

3 hours ago, TimG said:

On the Nikkor 8-15mm, I use a 20mm EFR with an 8" dome. Works a treat.

Good intel, thanks!

9 hours ago, horvendile said:

On another note, to my surprise I used the Nikon 8-15 fisheye very little on the trip. But my limited findings on using it with Sea&Sea housing are:

The lens chart recommends using no extension at all with the S&S 230 mm dome port. I tried this for the Zen 230 mm dome port; this configuration worked fine with the Sigma 15 mm fisheye. However, at 15 mm the Nikon shows the dome shade in the extreme corners. While the shade can be removed I don't want to do that, I just know I'll scrape the glass on some rocks. The only extension I had was 40 mm and using that the front of the lens ends up quite close to the glass in the dome port. I didn't like the look of that but never actually tried it in the water.

My idea is to get a 20 mm extension ring. Should be ok. Of course, cropping the images slightly is a cheaper option. With the Z7 I have a lot of pixels but yes I will lose field of view if I crop.

Edit: adding non-cropped image.
 

If you can see the corners of the dome that generally means that you have too much extension.  From what i read you are using the Zen 230mm dome with no extension or are you using 40mm extension?  You say adding a 40mm  extension resulted in the lens being very close to the port glass is this with the same 230mm dome?   Something doesn't add up right to me.  If the 40mm is too close to the glass, the 20mm will be 20mm closer to the glass than the 40mm.  Or do you mean the lens looked like it was buried in the extension? 

To solve the vignetting you need the front element a little closer to the dome and you do that by removing extension. adding extension buried it deeper in the dome and increases vignetting.

If you look at the port charts the Nauticam charts says a 50mm extension for the 14-30 with their dome, while S&S says 40mm extension on their dome.  This indicates  they re quite close in their extension requirements.   What is unkown is the difference in how deep the camera flange is in the housing.

4 hours ago, ChrisRoss said:

If you can see the corners of the dome that generally means that you have too much extension.  From what i read you are using the Zen 230mm dome with no extension or are you using 40mm extension?  You say adding a 40mm  extension resulted in the lens being very close to the port glass is this with the same 230mm dome?   Something doesn't add up right to me. 

You're right of course, I totally mixed things up in my head when writing that post. Funny thing is I started writing it in the correct way, then changed it to the mess it became.

So, with NO extension I got close the the glass and that looked wrong. Then I added 40 mm of extension (the only one available to me) and then the front lens was almost flush with the lens opening of the dome. This resulted in the shade being visible in the corners.

Thanks for pointing it out. Using 20 mm extension still seems reasonable though.

Note that this is for the 8-15 fisheye, not the 14-30.

6 hours ago, horvendile said:

You're right of course, I totally mixed things up in my head when writing that post. Funny thing is I started writing it in the correct way, then changed it to the mess it became.

So, with NO extension I got close the the glass and that looked wrong. Then I added 40 mm of extension (the only one available to me) and then the front lens was almost flush with the lens opening of the dome. This resulted in the shade being visible in the corners.

Thanks for pointing it out. Using 20 mm extension still seems reasonable though.

Note that this is for the 8-15 fisheye, not the 14-30.

Yes I'm talking 8-15.  Based on the port charts listings for the 14-30 on S&S and Nauticam, you need 10mm more extension on the Nauticam dome, compared to the S&S dome.  I assume you are using Zen 230mm with a S&S bayonet ring on it which is generally regarded as identical to the Nauticam dome?  To me it looks like the correct extension would be 10mm in this situation.  If you look at the Zen S&S port chart they list a 20mm extension for the S&S version of their 230mm dome.  I would expect that you would be OK with either extension as long as the 10mm did not vignette.