Reading A Refrac.

[TidalPete]

A slightly larger sample in a container will evaporate less than a smear on the prism since it has a higher ratio of volume to surface area. Plus, I drop my sample into a cup which I've just taken out of the freezer, so it chills to room temperature almost instantly.

Maybe if you're quick enough to close the cover you won't get significant evaporation, but I found I was getting artificially high readings by by dropping hot wort on the prism.

And +1 for pointing the end at the light, it really makes a big difference.

Thanks Malty,
I'll give it a go when I do my next brew & compare with my normal method.

TP :beer: