Thanks. Still struggling with the Macro extension tubes. Focus is HARD and I'm usually too lazy to bother with a tripod...although the mushroom one was with tripod. Using a tripod is great, as I can use Live View which does help a lot with focus because I can zoom right in and focus quite precisely.

Exposure is also tough. Shots seem to swing from under exposed to overexposed on a whim. I have to admit I haven't messed around with metering modes, maybe that would help.

The glow on the mushroom was achieved by just bumping the highlights to the max.
The yellow flower was almost posted SOOC, but I couldn't help myself.

Neither of these shots have been cropped very much at all, so that means I could print them quite large, which is something which directed me towards the Macro Tubes. Otherwise these shots are achievable without the tubes, but only at small resolutions.