This common frog (Rana temporaria) was photographed in the Rivelin Valley, Sheffield.
I wasn't 100% happy with the frog shot that I uploaded to Flickr yesterday: the angle of view was a little steep and depth of focus was way too shallow. This morning I went back to the pond and had another go.
I used a 50-200mm zoom lens fitted with an extension tube, which allowed me to get a bit closer to the subject. The main problem with using an extension tube is that the depth of focus becomes extremely shallow, so you have to use a very small aperture (high f number) to get decent results.
After taking numerous experimental shots, I eventually focussed on a frog that was hanging motionless in the water. The only sign of life was the occasional twitch of its nostrils.
Thankfully the frog stayed still long enough for me to take this shot. The camera was mounted on a low tripod, enabling me to get away with an exposure of 1/3 second.
The other essential equipment for taking this shot was a waterproof jacket and trousers - I ended up lying down in the mud at the edge of the pond!