Just brewed up an AG batch and had a weird experience.
At the end of the boil I grabbed a little sample for an OG test with the itty-bitty turkey baster/pipette thing that came with my refractometer. I set the sample aside for a while until the wort was cool and on its way into the fermentor. I then checked the sample, and it was low. Shockingly low - 1.062 when I was going for 1.081. At this point, the wort is almost completely into the fermenter, so it's a little late for a hydrometer reading.
So I clean off the refractometer and put in some water to see if it was properly calibrated. It reads 1.000.
I then pull off a bit of whatever wort is leftover in the kettle. Let it sit in a glass and separate (it's the full of break and hops, of course). When it does, it now reads 1.072.
That's better, but still off. Mostly, I'm confused as to why the refractometer would give different readings on different samples. This particular model is supposed to account for temp...but maybe not.
Maybe it's time to just go back to the trusty hydrometer...