Post by Joe Botting on Jan 25, 2007 10:26:47 GMT -5
Hi All,
Just wanted to show the spectacular differences that result from using different settings, based on one of Ormrod's fossil fish, from the Permian of County Durham. They were taken in a somewhat gloomy room, with daylight coming in from the left, and a standard lamp on the upper right.
Firstly, with flash:
The specimen is varnished, which gives the horrible reflectivity and glare, but the scales would be pretty reflective on their own. Note also there is very little relief, because the light is from head-on. Very short exposure time, of course, which can be an advantage.
Then, with simple long exposure:
The tone is very strange because of the warm incandescent lighting (i.e. a light bulb), and details are difficult to make out. Colours are nowhere near true, and this can make shapes and textures difficult to see.
Finally, we can use the 'incandescent' colour balance tool on our camera:
This is actually clearer than the original specimen. It's not perfect; in particular, the daylight is from too sharp an angle, giving deep shadows on even slight relief. For some specimens, that's ideal, but with this one, perhaps a 45-degree rotation towards the window would have been perfect.
All these are with a relatively large aperture, which reduces the depth of field but allows better resolution and shorter exposure times. Where we didn't use flash, though, the exposure was still around 15 seconds, so a tripod and cable trigger are essential!
Will post more experiments in future.
Joe
Just wanted to show the spectacular differences that result from using different settings, based on one of Ormrod's fossil fish, from the Permian of County Durham. They were taken in a somewhat gloomy room, with daylight coming in from the left, and a standard lamp on the upper right.
Firstly, with flash:
The specimen is varnished, which gives the horrible reflectivity and glare, but the scales would be pretty reflective on their own. Note also there is very little relief, because the light is from head-on. Very short exposure time, of course, which can be an advantage.
Then, with simple long exposure:
The tone is very strange because of the warm incandescent lighting (i.e. a light bulb), and details are difficult to make out. Colours are nowhere near true, and this can make shapes and textures difficult to see.
Finally, we can use the 'incandescent' colour balance tool on our camera:
This is actually clearer than the original specimen. It's not perfect; in particular, the daylight is from too sharp an angle, giving deep shadows on even slight relief. For some specimens, that's ideal, but with this one, perhaps a 45-degree rotation towards the window would have been perfect.
All these are with a relatively large aperture, which reduces the depth of field but allows better resolution and shorter exposure times. Where we didn't use flash, though, the exposure was still around 15 seconds, so a tripod and cable trigger are essential!
Will post more experiments in future.
Joe