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tamas970

Member Since 27 Dec 2012
Offline Last Active Jan 14 2016 04:51 AM
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Posts I've Made

In Topic: WTB: Subtronic Nova/pro270

04 January 2016 - 01:19 AM

I know where to get it new, just wondering if someone has a unit he/she doesn't use.
I know where to get it new, just wondering if someone has a unit he/she doesn't use + possibly save some .

In Topic: WANTED: Nauticam NA-SHOGUN Housing & Atomos Shogun

04 January 2016 - 12:44 AM

That is a ninja housing, the shogun is bigger.:(

In Topic: Upgrading from compact to 4/3 or dslr - advice needed pls

03 January 2016 - 01:36 PM

Once you put a good lens the full frame cameras kill any other set up in all possible combinations otherwise why do you think Dr Mustard shoots one?



He also shoots that FF setup with a zeiss wet corrector lens, designed for medium format cameras, rainbow unicorn category in the used market. Also seen some extralarge domes in his publications. My other favorite "advanced FF shooter" (although not photo but video with RED cameras) is Pawel Achtel: he is comitted to nikonos optics - for good reason.

Yes you can be unhappy with dome optics but flat ports at long focal length its anther story. The nikkor 105 at f/14 will resolve more than 3000 lines the Olympus doesn't resolve 3000 even at the best aperture and at f/8 resolves less than 2500 around 20% less. At f/22 the resolution of the 105 on a d810 is still better than the Olympus at f/8 and even at f/32 still resolves around 1700 lines. There simply is no comparison. However the magnification of a mft camera is always superior without add on lens. When I look at sample images taken with nikkor 105 and nauticam smc and compare those to the best mft i know which one is better for sure

Thanks for the values, saved me quite a bit of research. Thumbnail size images (especially on wetpixel...) don't help much here, one has to find 100% crops or resolution tests at e.g DXO. 20% advantage in resolution doesn't sound too much, it means you get 20% larger prints from the better camera. Game changer might be the new MP monster a7rII with the very-very good sony FE 90mm macro (however it might ask for a diopter, influencing quality).

Anyway I think we got a bit carried away from the op, the question is, what is the goal (shooting targets, print/publication sizes) and what gear complexity/weight/cost does the photographer feels confortable with.

In Topic: Upgrading from compact to 4/3 or dslr - advice needed pls

03 January 2016 - 06:17 AM

Pixel size of the 36MP D810 is 4.9 micron which requires around f8 to fulfill the Rayleigh criteria ( https://en.wikipedia...leigh_criterion, calculated with 500nm light), f32 was considered diffraction limited even in the film days. Here comes the question: in reality, which macro contains more details (same magnification provided): olympus 60mm, f8 or the DOF equivalent f14 nikon/sony 105mm? The nikon seems 2stops beyond Rayleigh's limit, the olympus less than 1 stop.

Right, a sony a7s (8.4micron pixel size) stays fine until f16. In comparison, the 16MP m43 sensor uses 3.75micron pixels, requiring around f6, make it f5.6, just a single stop over most FF cameras.
Speaking of domes, here are some discussions: http://wetpixel.com/...ic=54681&page=5 and a thorough test: http://www.borutfurl...es/dxfx-en.html . Obviously, high quality correcting optics and nikonos type lenses are exceptions, unfortunately both are rarely used by the uw photo community (corrector lenses -other than the wwl-1 - are difficult to find, nikonos is cumbersome+risky to use). To me the only real advantage of FF remained is the high dynamic range/more room in post.

A full frame camera is always superior to smaller sensors because diffraction doesn't kick in so soon. With the Olympus 60mm you start loosing quality after f/8 with a Nikon d7100 at f/16 but with a Nikon D810 the same 105mm lens can be used all the way to f/32 and it's very sharp. The story of sharp corners and depth of field only applies at comparable apertures you can push a full frame much further. At wide angle a mft has the sweet spot around f/4 but really you shoot at least f/5.6 behind a dome a full frame does require f/8 and more but there are more than two stops dynamic range of difference so that's not really an issue either. For macro though I believe the a7 series lenses stop at f/22 and that may be too little. I would look at a canon or Nikon full frame that usually have more stops


In Topic: Upgrading from compact to 4/3 or dslr - advice needed pls

03 January 2016 - 12:37 AM

Fully agreed on the strobes part, especially if WA has any importance. For pure macro though, 2xs2000's are perfectly fine for the job - here you will miss those sea fan, large anchor etc shots. 2xz240's or something even stronger would be ideal.

Larger sensors are also battling with corner sharpness issues. Even using the largest superdomes, a FF camera has to be stopped down to ~f11-f16 which takes away all the advantage (noise, even resolution because of the Rayleigh limit) the large sensor offers.

Or you can buy a second hand Panasonic GX7 (am selling it with Nauticam housing) or a second hand OM-D EM-5 or even EM-10 the difference in image quality is minimal although the newer camera have better handling and features you get camera and housing for £1,000 and can invest in strobes that by they way if you do macro are not necessarily too much cost
 
In terms of image quality nothing beats a full frame DSLR however the micro four third offer more magnification so if you shoot really small things an MFT with the Olympus 60mm is hard to beat