I don't know about others, but I'd enjoy hearing how you took the shot and what post processing you did.

It's shot on the reef in about 4m of water, just by the "blue-water" mangrove in Misool.
I told the audience last week that I found the widest lens that I could, and looked for a circular subject; as you can imagine, it's a bit harder than that when you get down to the details:
Nikon D200. Sigma 4.5mm fisheye, aimed straight up at Snell's window, two Inon strobes on sTTL, but -1 stop, pulled back about 10cm behind the base of a 120mm radius dome port with the shade removed. Manual exposure, set for the surface illumination. Photoshop CS4 RAW converter to tweak exposure and colour balance; saved dng file reprocessed in CS4 using "Noise Ninja" plug-in to sharpen just the lionfish on a new layer*, and then adjusted in curves and colour balance. A few bubbles removed with the patch tool. Output as psd and jpeg.
* selected by painting a white mask over the fish on the sharpened layer; I use a WACOM tablet and pen quite a lot when working with layers and selections
The hardest part? Waiting for the fish to swim right over the dome (about 10cm above it, in the best image), and holding your breath so as not to disturb Snell's window...
... and being asked if it was a composite image!
Two other attempts:


I cloned out an image of my regulator from one image.
I wanted to shoot Snell's window through the mangroves (see my Raja Ampat "Ultimate Indonesia" posts for examples), but that didn't have the impact of the lionfish. Maybe the image works because it's a different take on a familiar subject? I would have liked the lionfish to look at its reflection in the dome, but that didn't happen.
Tim
