Saturday, 8 October 2011

The Shrine


Day one in Osaka. To find interesting places to photograph I usually scour all the literature you can pick up in hotels, or tourist offices. One Osaka map I grabbed had a photo of an interesting crimson half-moon bridge in a park so we headed off to find it. It turned out to be easy to find: five stops on the local train line towards Kansai airport on the Nankai line and we were there: walk out of the station and turn right to go into the shrine. In fact the station is in the middle of a large park so it almost felt like being in the countryside. Quite a surprise so close to the centre of Japan's second largest city.
HDR image, Canon EOS 60D
HDR image, Canon EOS 60D
HDR image, Canon EOS 60D
HDR image, Canon EOS 60D
HDR image, Canon EOS 60D
The following shots were all taken by Saima Morel (aka The Image Doctor from Australian Photography magazine) using the new Panasonic Lumix GF3 - she had never used this camera before. The results were pretty good. Images were post-processed in Photoshop with minimal tonal changes.
The exposure on a bright sunny day was hard to get right as the contrast level was beyond the reach of the camera sensor. The only alternatives were to shoot triple exposures and put them together using HDR software like Photomatix Pro or, as with the majority of the mages seen here, simply to underexpose dramatically to retain highlight details - at the expense of the deep shadows. At any rate this really did not matter because doing this produced a good impression of what it was really like on the day. 


How to Shoot HDR
Any scene has a certain dynamic range - the number of tones between black and white. Cameras can record only a limited dynamic range, usually seven to nine f-stops of exposure. A typical sunny day has a wider dynamic range than a sensor so a DSLR fails to record highlight and/or shadow details. But, if you record several different exposures of the same scene (on a tripod) you can cover all of the extended scene dynamic range. The trick then is to 'squeeze' them into the more limited gamut, or range, provided by our viewing and printing devices (i.e. the monitor and desktop or commercial print press). HDR software helps us do this by literally discarding the under and over-exposed parts of the bracketed images to leave a range of tones that no DSLR can capture in one shot alone.
Interestingly many HDR shots do look a little odd. This is because we know that we often can't see all the tones at once as the human eye only focuses on one point in the scene at a time. So when all the tones are presented in a two -dimensional print as a 'fait accompli', it looks slightly surreal. HDR software can be used to make this effect more realistic or, in some cases, to exaggerate the surreal nature of the visuals to produce an image that's more illustration than photograph.
The technique is to shoot in the camera's AEB (auto exposure bracketing) mode to get three or more different exposures that cover the dynamic range of the scene. Typically one to two f-stops apart from each other (i.e. '+ two', 'normal' and '- two'). High-end Nikons can capture three, five, seven and in some models, nine images in one long bracket. The closer each bracketed frame is in terms of exposure, the more accurate the result and the better its quality. Canon cameras only create three frame brackets. If you want best quality (by 'best' I mean less noise) then it's better to make the exposure adjustments one f-stop apart in manual metering mode.
Note that RAW files produce better, 'cleaner' results than JPEGs, although I always shoot both at the same time. The humble JPEG is much faster to process, especially on a laptop. If I get a good result from the JPEG version, then I repeat the process on the RAW files.

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