Photograph Works

My diary in photographs

  • Richard Serra sculpture in the garden at MOMA in New York

    Woman appearing to be praying before the Richard Serra sculpture in the garden at MOMA. Or she could be – in fact is – looking at the shot she had just taken with her camera. The surface of the huge iron sculpture is pitted with rust.

    There are more of his sculptures in the building and some are so big I had to ask how they got them in there. The answer is that the wall rolls back and a crane hoists them in.

    MOMA, the Museum of Modern Art in New York, is a beautiful building and it that grabs the light streaming in and diffuses it wonderfully.

    Serra at MOMA

  • Depth of field (with gecko)

    My wife found this little guy in a pail in our third floor apartment in Jerusalem. He is an Mediterranean Gecko. Geckos (I have to ask myself whether I am completely sure of the plural of Gecko) have the ability to climb surfaces without the use of any adhesive secretions or liquids on their feet. Rather they use the elecromagnetic attraction that exists between molecules.

    I took this at 1/50second at f5.6 at ISO 800 with a Nikon D40 with the 18-55mm kit lens, held with my free hand while the gecko showed me his better side. The make-up artist was away, so we had to shoot without makeup.

    Technically, it illustrates that at very short subject-to-camera distances, the depth of field is very small. The gecko’s face is probably in focus. It is hard to tell because he was moving and any lack of sharpness may be doing to subject movement, but he is not far off being as sharp as my knuckle. But everything back from that is falling rapidly out of focus.

    If I has shot him with a long lens at a greater distance but with the same focal length, more of him/her would be in focus.

    gekko

    No geckos were harmed in the making of this shot.

    _______________

    And here is a thumnail of a larger version of the shot, Click it to see the larger view.

    gekkobig

  • How sharp are digital images?

    The level of detail in the camera held in the woman’s hand is amazing. This is especially so considering the shot was taken hand-held in poor lighting.

    D200 with 12-24mm lens 1/20 second at f4. 800 ISO.

    museum

    Crop showing the camera in the woman’s hands.

    museum phone

  • Vibration reduction with Nikon lenses

    Nikon builds vibration reduction into some of its lenses, as does Canon. Not all Nikon’s lenses have vibration reduction and for very short focal length lenses it is not necessary. Vibration reduction, or image stabilization as some other manufacturers call it, stabilizes the camera. It does not stop the subject moving so it is no advantage in sports photography where very fast speeds are required. But it is useful in low light.

    In the Nikon Imaging site, a Mr Kazutoshi talks about the development in vibration reduction technology in Nikon lenses. He says that VRII, the second generation incarnation of this technology means that:

    The detection of the low frequency band in camera shaking has been greatly expanded, so the VR effect has become available even if the shutter speed is quite slow. I believe that a VR effectiveness equivalent to about four stops in shutter speed covers most shooting conditions. When we were test shooting during development, we couldn’t assess the effectiveness of four stops in shutter speed until well after the sunset, so we had to shoot through the night for some time.

    For those not familiar with what four stops in shutter speed means, cameras are designed so that there is a constant relationship between the aperature and shutter speed. Each stop opening up the aperture, doubles the light that gets into the camera during the shot. And shutter speeds double in the same way, so that it is meaningful to measure an increase in one stop of light by saying it is equivalent to a doubling of the time the shutter remains open.

    So translating this into what we can acheive with Vibration Reduction on a Nikon lens, let’s suppose I am shooting a lens with a focal length of 135mm and that I using a camera with a crop factor of 1.5, (which means all of Nikons DSLRs with the exception of the new D3, which is full frame).

    So the 135mm lens has a field of view equivalent to a 200mm lens (more or less) in a full frame 35mm film camera, which is the standard that focal lengths for lenses are described against.

    Now it is generally accepted that to be pretty sure of getting a sharp shot hand-held, the slowest shutter speed should be no slower than the reciprocal of the focal length, in other words for a 135mm lens on a digital SLR with a 1.5 crop factor, the slowest shutter speed I should use is 1/200th second. (more…)