223 replies to this topic

[loftus]

I think the 8" dome is too small for this lens, 9" like the Zen 230 is significantly better with FF and rectilinear wide angle lenses.

[Rene Zuch]

One inch less should make it so bad? I can't believe that.

[loftus]

I have both; it makes a difference with rectilinear wide angle, especially on FX. Of course your port extensions may be at issue as well - but you will find it difficult to get sharp corners with an 8" dome on FX with this lens. My own personal opinion is that the 7D is a better all around underwater camera as a cropped sensor camera. There are some specific areas where the D800 will excel, but overall will be more difficult to use. If I had to choose only one underwater camera for all purposes, it would be my D7000.

Edited by loftus, 07 August 2012 - 02:35 PM.

[Rene Zuch]

What exactly do you mean with "I have both"?

Can you tell a bit more or post som pics that I can judge?

Thanks René

[loftus]

I will qualify that - I had both as I just sold my Subal 8" with my D700 housing. However I did own both for about a year, and pretty much switched exclusively to using the Zen 230 from the Subal 8" with the 16-35. I found the corner quality significantly better - judged mostly from my pool photography work with models, finding less distortion of feet and hands which tended to be towards the corners of the frame. During this time I also changed from the 17-35 to 16-35 which I found worked better underwater (as Alex has found) and also does not require a diopter. I will search back in some of my images to see if I can demonstrate what I mean. I think there is some general consensus that wide angle rectilinear lenses need larger domes on FX particularly, hence the superdomes from Seacam and Aquatica as well as Zen. This is even more the case with the 14-24. Of course this is not peculiar to Nikon, the same applies with Canon cropped vs full frame sensor cameras.

Edited by loftus, 08 August 2012 - 06:00 AM.

[Kogia]

Jeff -
I'm very interested by your comment that you would choose the D7000 over the D800. In theory for shooting wide angle with the D800, there could be a number of advantages (such as improved frame rate) to putting a 10-17mm on the D800 and shooting it in DX mode, which would still give you about 18MP. Are you able to compare the results of D800 wide-angle DX mode with D7000 wide-angle? If those results are similar, the D800 might seem a better choice since you could use it in FX mode for macro with strobes and get more resolution and more cropping options, but switch to DX for wide-angle, and avoid the drawbacks that Alex has mentioned of shooting wide on full-frame, such as having to use only big domes and needing to use the Sigma 15mm instead of the 10-17mm.

[Alex_Mustard]

In theory for shooting wide angle with the D800, there could be a number of advantages (such as improved frame rate) to putting a 10-17mm on the D800 and shooting it in DX mode, which would still give you about 18MP. Are you able to compare the results of D800 wide-angle DX mode with D7000 wide-angle? If those results are similar, the D800 might seem a better choice since you could use it in FX mode for macro with strobes and get more resolution and more cropping options, but switch to DX for wide-angle, and avoid the drawbacks that Alex has mentioned of shooting wide on full-frame, such as having to use only big domes and needing to use the Sigma 15mm instead of the 10-17mm.

I can add some thoughts on these. I think the main disadvantage of using the D800 in DX mode is that you end up with a small viewfinder. The D800 gives 15MP compared with the D7000's 16MP - which can be assumed to be pretty much consistent. The D800 has faster synch speed with electronic flash (in DX mode) and better AF system. In theory the D800 has better dynamic range at a pixel level - but in the field people are not seeing a big difference over the D7000.
But both are noticeably noisy at higher ISOs compared with FX cameras (the D800 on FX included) - remember the D800 is quite noisy at a pixel level - this is irrelevant in FX mode because you have so many pixels - but is relevant in DX mode (where you are not using more than 20MP).

The other advantages in running the D800 in DX mode are for smaller file sizes and for specific uses (many UW photo competitions) where cropping in post is not allowed.

But for most users the best option is to shoot it in FX - and crop when needed. An FX file cropped back to a DX file gives you the same equivalent angle of coverage range as the 10-17mm does on DX. And if you only shoot fisheye on FX you can get away with a smaller dome. This was shot on FX with 6" acrylic dome with Sigma 15mm.



I don't think using fisheye + teleconverter is worth it on the D800 if you want to maximise image quality.

Alex

[Rene Zuch]

I can add some thoughts on these. I think the main disadvantage of using the D800 in DX mode is that you end up with a small viewfinder. The D800 gives 15MP compared with the D7000's 16MP - which can be assumed to be pretty much consistent.
Alex

Hi Alex,

as you can read in that post I realized that DOF is much smaller with the D800 compared to my former Canon 7D Crop camera and I had some problems doing Macro (Supermacro). I guess that´s not changing when I switch to DX mode? As holidays are gone for this year I won´t be able to try.

Regards
René

[Rene Zuch]

By the way for Ikelite users. I think the port recommendation for the 16-35mm is completely wrong.

I calculated by myself based on the nodal point and port radius and found out the port should be arround 2,5 cm further away from the camera. I will try to go to a pool on sunday and proof that.

As I said, I think one inch less cannot make it so bad.

/René

[Rene Zuch]

Hi,

I made my tests with the dome positioning and found out it works much better with my calculated Dome positioning.

Every Ikelite user with the Nikon 16-35mm and the 8" Dome should not use the #5510.28, but the #5510.22 + #5510.58. With that combination the port is further away from the camera. The angle of view is wider, the corners are much sharper and there is no vignetting anymore. Especially at f4 you can clearly see the difference.

It´s still not perfect, but much better and at least usable. On the last pic I made an exmaple with f14 and there it looks pretty good.

Here you can find all the pics at f4 and f9 and judge by yourself:

http://uw-digi.de/dometest/

Regards René

Attached Images

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[ToddB]

Just got back from taking a D800 to guadalupe. I brought my D7000 along as well, in case the D800 didn't work out, but never wound up getting it wet. I only received the camera two days before departing and have never shot FX before, but I was pleased with how things went. It was a challenge, I did miss the extra FPS, and I definitely got fewer keepers than I'd like, but the detail in some of my shots where focus was spot on is just awesome imo. I'm sure the camera can do better as I get more familiar with it, and I think I'm set on selling my D7000. Below are a couple of the first shots I've gone through, all uncropped except the first slighty (its 34 MP). The b&w was @ 105mm. I brought 16-35 and 15mm, zen 230. About 75% of my shots were with the 16-35, but in hindsight after scrutinizing my shots more closely now on a big screen, I would have kept the 15mm on close to 100% of the time and just cropped in post if needed. I'm finding the 15mm images to be sharper and more pleasing overall.

[Alex_Tattersall]

Very impressive, I do like the black and white!

[Alex_Mustard]

Every Ikelite user with the Nikon 16-35mm and the 8" Dome should not use the #5510.28, but the #5510.22 + #5510.58. With that combination the port is further away from the camera. The angle of view is wider, the corners are much sharper and there is no vignetting anymore. Especially at f4 you can clearly see the difference.

Very interesting, Rene. What are the the approximate total lengths of the port extensions in the two examples?

Alex

[loftus]

Thanks for that Rene. Where does the front lens element sit in relation to the dome port?

[Rene Zuch]

Very interesting, Rene. What are the the approximate total lengths of the port extensions in the two examples?

Alex

With the #5510.28 (recommended by Ikelite) it´s 70mm (2,75") and with the #5510.22 + #5510.58 it´s 90mm(3,54").

@Alex
Can you answer the question I passed to you earlier in this thread over the DOF in DX mode compared to FX mode?

Thanks for that Rene. Where does the front lens element sit in relation to the dome port?

I´m not sure if I understand your question correctly. I based my calculations on the entrance pupil (nodal point). The distance between that nodal point and the dome is equal to the radius of the dome (in my case 4").

You can look also at the attached pictures:

Before:


After:


René

[Alex_Mustard]

as you can read in that post I realized that DOF is much smaller with the D800 compared to my former Canon 7D Crop camera and I had some problems doing Macro (Supermacro). I guess that´s not changing when I switch to DX mode? As holidays are gone for this year I won´t be able to try.

No difference to DOF if you shoot the D800 in DX mode. But you end up with a v. small viewfinder image if you do.

Alex

[loftus]

OK; that's what I thought. I think another way to get in the ballpark, rather than calculating nodal point etc is to place the front element more or less flush with the entrance to the dome. At least with Nikon most 8"domes are designed for the 16mm with the front element flush. In the before pic your lens sits quite far into the dome. Probably not as accurate as calculating nodal point, but probably a good starting point when choosing lens extension.

Edited by loftus, 21 August 2012 - 05:28 AM.

[SiuBing]

hi,

i have a question for those who has used the nauticam housing for d800. is there a button for you to change between af-s and af-c foucs mode?

[loftus]

hi,

i have a question for those who has used the nauticam housing for d800. is there a button for you to change between af-s and af-c foucs mode?

Yes

[SiuBing]

Yes

thanks for your quick reply, loftus.
good to know that nauticam has that botton. my nexus d800 housing only has the switch for AF/M but not the button for changing between AF-S and AF-C.
seems nikon do not provide the switch from the menu. do you know any way to do that? 8-(