https://www.bhphotovideo.com/c/product/1812335-REG/sony_fe_24_50mm_f_2_8_g.html/specs

 

440g, 67mm filter size, 18cm minimum focus distance (0.33x magnification), US$1098 list price - possible higher quality alternative to 28-60/28-70mm behind WACP-C/WACP-1/FCP? Doubt it will work behind WWL-C/WWL-1 with this large front element.

Extends by what looks like an inch or so as you zoom in - see Sony video. MFD increase to ? 29 cm at tele end (18 cm at wide end). So needs a large radius dome to make use of full range (or just use it at wider end with smaller dome).

Actually, it extends at 24mm, and retracts at 50mm according to this youtube video. So it should be possible to use behind a WACP-1 at least without vignetting. The same video claims the image quality is quite stellar

 

Regarding the 67mm filter thread size, the Canon RF 14-35mm F4 has a 77mm filter size, and that lens works with both the WACP-1 (personally tested) and the FCP according to the port charts. So it's promising. It should work with at least the WACP-1 and FCP, and perhaps also with the WACP-C.

 

If it does.. well, it would be quite a goldilocks lens for Nauticam's smaller water contact optics. Exciting times in Sony land. 

It will be interesting to see if it works with the WWL as well, or will it just have significant vignetting? 

2 hours ago, DreiFish said:

Actually, it extends at 24mm, and retracts at 50mm according to this youtube video.

Correct. My mistake watching the Sony video and not seeing the scale. Internal zooming is preferable for U/W, if you have a choice.

7 hours ago, RVBldr said:

It will be interesting to see if it works with the WWL as well, or will it just have significant vignetting? 

I think the front element is too big for that.

Although the 28-60mm is a kit lens (and therefore is regarded by some to be inferior) it is quite a sharp lens, much better than the older Sony 28-70mm  (see e.g. https://dustinabbott.net/2020/11/sony-fe-28-60mm-f4-5-6-review/ or https://www.the-digital-picture.com/Reviews/Sony-FE-28-60mm-f-4-5.6-Lens.aspx)...

 

Therefore I think that an alternative lens for WACP/WWL-1 is not really required (only 28mm and up are useable with these optics and 50mm is not so much). It would be great if WWL-C, that requires 24mm and up, would be working with this lens (but maybe the lens is too big)...

 

Wolfgang

I think the filter size is perhaps a proxy for front element and entrance pupil size.   What has to happen is that the light bundle that corresponds to a 130° field has to fit through the entrance pupil.  The entrance pupil is generally much smaller than the front element, so the front elemnt needs to capture the light bundle and as it passes through the elements in front of the entrance pupil it needs end up at a size that fits through without vignetting. 

 

The 14-35 is mentioned and that is on the FCP port chart and it was mentioned it works with the WACP-1 - presumably this is at 28mm focal length.  The combination of front element and entrance pupil size and location would be allowing the light bundle through.  The point of all this is that the lens in question 24-50 would potentially work with the FCP but the WACP-1 is probably less likely as it seems to favour 28mm f3.5 or f4 optics.  We won't really know until someone tests it.

On 2/23/2024 at 4:12 AM, Chris Ross said:

I think the filter size is perhaps a proxy for front element and entrance pupil size.   What has to happen is that the light bundle that corresponds to a 130° field has to fit through the entrance pupil.  The entrance pupil is generally much smaller than the front element, so the front elemnt needs to capture the light bundle and as it passes through the elements in front of the entrance pupil it needs end up at a size that fits through without vignetting. 

 

The 14-35 is mentioned and that is on the FCP port chart and it was mentioned it works with the WACP-1 - presumably this is at 28mm focal length.  The combination of front element and entrance pupil size and location would be allowing the light bundle through.  The point of all this is that the lens in question 24-50 would potentially work with the FCP but the WACP-1 is probably less likely as it seems to favour 28mm f3.5 or f4 optics.  We won't really know until someone tests it.

 

Hi Chris,

 

As said, based on my experience with the Canon 14-35 F4, which works great with the WACP-1 between 28-35mm (even though not listed on Nauticam's official port chart), I'd expect this 24-50 to also work with both the WACP-1 and the FCP.

 

This is the Canon 14-35 F4 with the WACP-1 at 24mm F4.0 (yes, wider than the advertised minimum -- and the lower and upper lens hood show a little bit as a result. But they go away at 26mm. 

 

Andrei 

 

 

Anyone thinking of putting this to the test?

Hi - well, nobody did any tests so far? Even on land?

https://www.digitalkamera.de/Zubehör-Test/Sony_FE_24-50_mm_F2_8_G_im_Test/14107.aspx

 

I'd like to add the review above that sounds quite promising and in the pictures you can see also the extension at certain zoom-levels. But as @Architeuthis Wolfgang said, it would probalbly not improve image quality under water in relation to the 28-60 but reduce zoom range. Maybe that's why no one used it so far under water.

1 hour ago, fruehaufsteher2 said:

https://www.digitalkamera.de/Zubehör-Test/Sony_FE_24-50_mm_F2_8_G_im_Test/14107.aspx

 

I'd like to add the review above that sounds quite promising and in the pictures you can see also the extension at certain zoom-levels. But as @Architeuthis Wolfgang said, it would probalbly not improve image quality under water in relation to the 28-60 but reduce zoom range. Maybe that's why no one used it so far under water.

 

When one compares test photos between the 28-60mm and the 24-50mm at comparable focal lengths and apertures, one can see that the 24-50mm performs pretty similar, the 28-60mm is maybe even a small bit sharper:

https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1525&Camera=1175&Sample=0&FLI=0&API=0&LensComp=1687&CameraComp=1538&SampleComp=0&FLIComp=1&APIComp=2

 

=> Since the wider f/2.8 aperture and 24mm are not needed UW (in connection with WWL/WACP), I am not tempted to buy and test the 25-50mm for UW use...

 

 

Wolfgang

Edited January 8Jan 8 by Architeuthis

I am beginning to think that the Nauticams wet optics are just not good. And so no lens behind these wet optics WWL WACP etc will make a difference on the quality of picture. In fact I am beginning to think that these optics are wrong way to go. During my quest to check how fisheye lens would work for me I made series of picture in my home pool and the results of WWL1 with 28-60 were not favorable compared to such basic lens like 16-35 F4 PZ behind just a 180mm glass dome. Judge for yourself, all details are 300% and white box in left corner thumbnail  shows the positions of enlargements. 16-35 performs much better even when its at F8 while WWL lens is stopped down to 13. I have disabled profile correction for 16-35 so it shows kinda barrel distortion like you might prefer for shooting in water to make the subject pop. With profile enabled it would be strictly rectilinear.

 

 

 

Edited January 13Jan 13 by RomiK

Thanks for the test. The bottom RH corner shots seem sharper than the others (3rd and 2nd last pics). Any chance there are some focus issues eg. small target / camera close to target and not square on?

Hi Romik, 

 

I think (but might be wrong) you are comparing fisheye (WWL1) with rectilinear (16-35 PZ). That makes necessarily a huge difference in the corners. 

 

The advantage of the wetlenses is the wide coverage of angles of view (70-130°) with reasonable sharpness and (-C) relatively small size at the cost of a higher weight. No size fits all. 

 

 

11 hours ago, dentrock said:

Thanks for the test. The bottom RH corner shots seem sharper than the others (3rd and 2nd last pics). Any chance there are some focus issues eg. small target / camera close to target and not square on?

These are center frame images if we talk about same images (2nd and 3rd from the bottom).  They seem to be sharp but sharpness falls more dramatically for WWL1 than for 16-35 comparing center and sides.

 

I was laying on side of the pool and held the camera in the water looking down. The distance to mat was around 1m, the size of mat was 90x120cm. Light was provided by a 10000 lumen video light on my rig and light position changed with each lens exchange. hence the difference in scene lightning between lenses.

 

11 hours ago, fruehaufsteher2 said:

Hi Romik, 

 

I think (but might be wrong) you are comparing fisheye (WWL1) with rectilinear (16-35 PZ). That makes necessarily a huge difference in the corners. 

 

Yes, these were two lenses although technically WWL1 is paired with 28-60 and is classified as wide angle with kinda fisheye effect, the FCP is their fisheye. So yes the corners would be different and if anything I would expect - as Nauticam claims - the corners of WWL1 being sharper than 16-35. Which is the opposite even when WWL1 has more then 1 stop advantage. 

 

11 hours ago, fruehaufsteher2 said:

The advantage of the wetlenses is the wide coverage of angles of view (70-130°) with reasonable sharpness and (-C) relatively small size at the cost of a higher weight. No size fits all. 

 

 

 

That`s another thing that struck me - no clear advantage in FOV. Perhaps few percent if that and achieved by bending corners if anything else. Of course this is for WA, I will have to make another test for CFWA and see how the depth of field and minimum focus distance would play into this. But as far as WA goes it seems the lens and dome have advantage with sharpness and micro contrast. And that was 180mm dome while 230mm would bring even more superior corner performance (but who would want to travel with that 🙂 ).