Commons:Featured picture candidates/Image:Japanese Stewartia Stewartia pseudocamellia Bud 2000px.jpg

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Image:Japanese Stewartia Stewartia pseudocamellia Bud 2000px.jpg, not featured[edit]

Stuartia pseudocamellia

  •  Comment This is an extremely close macro, at close to 1:1 reproduction. The depth of field at that distance is only a few millimeters deep. This image is shot at f/11. Any higher would start to degrade sharpness due to light diffraction. I didn't see a good reason to degrade bud sharpness to increase the depth of field by perhaps a millimeter or two at the stalk. The point of this image is to show the two buds in high resolution detail. Everything is natural, this was not a posed shot. Just because it isn't a flower or a cone doesn't mean it isn't beautiful or useful. -- Ram-Man 18:04, 7 May 2007 (UTC)[reply]
  •  Info I don't know the exact conditions this picture was taken under and I'm pretty much sure you know about that, but there are other ways to increase DOF than using smaller apertures. You could have got closer and use a shorter focal length for instance. Framing would have been the same but with a greater DOF. And this picture is good, but not much above average and if I support this one, then I'd support plenty of others... Benh 06:27, 8 May 2007 (UTC)[reply]
  • No, I couldn't have gotten closer. At 1:1 magnification, I was already at the limit of the lens. You'd need a micro lens (as in microscope, not Nikon) to get closer. Ignoring pupil magnification effects, if the image in the frame is held constant, the DoF is basically constant as well (see here), regardless of the focal length used. Shorter focal lengths wouldn't work here, even if you include pupil magnfication which gives additional advantage (if anything) to telephoto lenses. Increasing the depth of field further would have required work outside of pure photography, such as image stacking of different exposures in software or some other trick. -- Ram-Man 12:13, 8 May 2007 (UTC)[reply]
  • This is getting far :) (and the DOF issue wasn't really my reason for opposing :)) but that's an interesting thing you tell me here. If I take the exemple described in the page you linked (paragraph focal length and depth of field), for a given framing DOF is, as you said, virtually constant but it seems the shorter focal length still have a few extra cm in DOF (up to 8cm which could have been enough for your subject). Wouldn't have this been sufficient (of course, this is given you have a (macro?) lens which can focuse at short distances) ? Benh 21:06, 9 May 2007 (UTC)[reply]
  • As far as I know, there is no such thing as a 1:1 magnification 10mm-20mm macro lens in the SLR format, although some point and shoots can do macro at that focal range, but most point and shoots suffer from severe lack of edge sharpness when that close and they suffer more quickly from diffraction degradation. Plus the table provided wasn't for macro. Apparently at macro settings the slight DoF advantage of wide angle lenses is lost anyway due to pupil magnfication. I realize that the reason this FP nom failed was not because of DoF but because of the other issues given. I've just noticed that in a number of situations there is a misunderstanding on how DoF works. Take this orange slug FP nom taken at 5mm with a small point-and-shoot. Even at only f/2.8 that image has almost the ideal depth of field/sharpness possible, due to the focal length of 5mm. -- Ram-Man 21:18, 9 May 2007 (UTC)[reply]
  • The only potential way to make this picture sharper would be to take the picture at a different angle so that more of the stick lies in a single plane perpendicular to the camera lens, that is, put more of the subject in the DoF range. However, the twig was blowing mightily in the wind and this was the best of a whole bunch of pictures. -- Ram-Man 21:34, 9 May 2007 (UTC)[reply]
result: Nomination withdrawn => not featured. Simonizer 07:04, 9 May 2007 (UTC)[reply]
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