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Alex_Mustard

Member Since 16 Jan 2003
Offline Last Active Jun 23 2017 07:06 AM
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Posts I've Made

In Topic: Nikon 8-15mm in the house!

23 June 2017 - 01:45 AM

Really enjoying this conversation and wanted to be involved even though I haven’t seen the lens yet. 

 

I am really keen to try this lens. For some reason availability has been very limited in the UK, but I am grateful to Adam for lending me his to shoot in the Red Sea.

 

However, away from the glitter of new gear, I don’t find this lens that enticing on paper. As we already know from the Canon 8-15mm, the zoom range is not that useful on a full frame camera. Nikon market it as two lenses in one, rather than a zoom, and I think that this is a good way to think of it. That said, I am not a fan of circular fisheye shots (despite using one as the opening image inside my recent Secrets Of The Seas book!), and I don’t want to dive routinely without protective dome shades (even though they easily unbolt on my Zen domes). 

 

So for me, on full frame, it comes down to whether a Nikon f/4.5 15mm is better than a Sigma f/2.8 15mm. And I don’t think it will be by enough to get really excited about. (I will still buy one because, like Adam, I have both FX and DX underwater systems.

 

Like many I would have been much more excited if Nikon had made an updated replacement for the Nikon 16mm f/2.8, one that focused close and had image stabilisation. In my experience the Nikon 16mm has always been better at handling the sun than the Sigma.

 

However, the big difference between the Nikon and Canon Full frame 8-15mm fisheyes is that the Canon 8-15mm is clearly the best fisheye for underwater use a full frame Canon user can buy, even if they only shoot it at 15mm. This is not the case for Nikon users. Not only might this lens offer little compared to Sigma 15mm, Nikon users have the option of the Nikonos 13mm. 

 

The Nikonos 13mm offers little advantage over a Sigma 15mm and 230mm/9” dome at apertures of f/13 or above. Except that its small size (lack of dome) makes it much easier to light subjects very close to the camera. The strength of the Nikonos 13mm’s water contact optics is with subjects shot in the range f/11 down, where is out performs any lens behind a dome very noticeably. This is especially exciting for full frame users, because rather than giving away aperture to DX users to achieve comparable corner sharpness, you actually gain aperture! Of course the Nikonos 13mm cannot shoot split levels, which is a significant limitation, especially as these are amongst the most commercial type of wide angle underwater images. 

 

For me the final piece to puzzle might be the new Wide Angle, water contact fisheye system that Nauticam are developing. This is not a 180˚ lens, but has a tighter angle of view with a FOV range of about 60˚ to 130˚, but with the advantage of being able to shoot at more open apertures and still giving excellent corner sharpness, because of being designed solely for in water use (can’t do splits either).

 

The downside of both the Nauticam lens system and the Nikonos are that both are expensive solutions. The Nauticam port is also heavy because it involves a lot of glass!

 

Alex


In Topic: DX to FX and back again

05 June 2017 - 04:44 AM

I’ve continued to use both, since the D3 came out. But increasingly I use the FX option (in my case D5) for more and more of my photography.

 

I think a major reason in this (apart from the D5 being an amazing camera - if you like the D500, you’ll love the D5, it is even more of the same) is the FX wide angle solutions I am using. Three of which are water contact optics (I use 3 - RS-13mm, Zeiss Ivanoff with 20mm, and Nauticam’s forthcoming lens). These at the very, very least negates any advantage that a DX system has regarding corner sharpness, therefore allowing me to shoot at more open apertures and restoring the ISO advantage of an FX body. 

 

ISO flexibility is a huge part of how I shoot underwater and FX does this best. This is something that I value even in bright, topical destinations, because it is not bright everywhere! Below are a couple of examples - the first from my first 2000 shots in Cayman Dec 2016 to show the spread of ISO values I used (all set manually, no Auto-ISO):

 

Attached File  15203293_10158058969615713_8451019032236091881_n.jpg   20.35KB   12 downloads

 

This example is from the Wetpixel workshop in Lembeh Oct 2016 - also with Nikon D5 (although I think it includes some shots taken with D500 and some with my Olympus):

 

Attached File  15192744_10158060005940713_4919480646191499121_n.jpg   20.39KB   12 downloads

 

Alex

 

 

 


In Topic: How to get sharper corners when using E-mount 12mm Zeiss in Ikelite housing a...

02 May 2017 - 11:20 PM

Thank you! The resolution here is perfect for the talk. 

 

Do you want me to credit you when I show it, or not? It is a great examples of the classic problems that many people find. 

 

Alex


In Topic: How to get sharper corners when using E-mount 12mm Zeiss in Ikelite housing a...

02 May 2017 - 02:01 AM

First of all - your shot is a great example of the classic problems of wide angle underwater. Solving these problems is something many have to go through. Please can I use your photo as an example in my presentation on this topic?

 

The cheapest fix you have to improve the situation is to close the aperture. You should try and be at least f/11 on an APS-C camera. On full frame that needs to be f/13-f/14. Take a series of shots at f/8, f/11 and f/16 on your next dive - and you will see how the corners get better. 

 

Next up it is important that the dome is correctly positioned. Just because the lens fits behind the dome - does not mean it is correctly placed. This means using the correct port extension. Manufacturers should know this and give you the correct advise at purchase - but we so many many new lenses appearing - their advice is not always right. A poorly positioned dome port will ruin your image quality.

 

(A dome should be positioned so that the centre of the sphere that would be made by the dome is in the same place as the lens's nodal point (the point in the lens where the light rays converge) - however, in practice it is not always easy to find out the exact position of either! So we tend to learn by testing and then sharing what port extension works best).

 

A larger (more expensive) dome port will help too. But only if it is correctly positioned. A larger dome in the wrong position will be worse than a smaller dome in the correct position. 

 

Alex


In Topic: Nikon Comparison D500 vs D7200

02 March 2017 - 11:42 PM

The extra money in the whole system price is quite small, so worth it.

 

But if you can find a secondhand D7200 system, then that would be very attractive. 

 

Alex