Need help using the refractometer
I bought a refractometer off amazon last year to help me judge when the syrup is done. One issue I have so far is that the blue/white line seems to climb the longer you leave it up to your eye. I'm thinking that I might be putting too much liquid onto the prism and that it is flowing down the slope as I hold it up to my eye and maybe that is shifting the refraction a bit. Occasionally I get a sharp blue/white line but more often its a litte blurry and shows a gradient. Do any of you have tips or tricks for using this tool?
2017 - 45 taps on buckets 260gal sap 6gal syrup
2018 - 92 taps on bags
All boiled on a homemade 2x5 fuel oil evaporator using 6 steam pans