Calibrating Refractometer

[btkrausen]

I was checking my calibration of my refractometer, and wondered how the solution can be 35 ppt refractive index and 1.3394. When I look into my refractometer, these two are on different levels.

Should I calibrate to the 35 on the right side of the refractometer, which is represented by a o/oo or the right side, which is D 20/20.

Mine was right on 35 on the right side, so I hope thats correct.

 

[BeakerBob]

When you say they are on different levels, do you mean straight across from each other?? If so, the 1.3394 is the Refractive Index, not the Specific Gravity. Use the 35 ppt marking.

In a salinity refractometer, 35 ppt = 1.0264 SG

 

[btkrausen]

When you say they are on different levels, do you mean straight across from each other?? If so, the 1.3394 is the Refractive Index, not the Specific Gravity. Use the 35 ppt marking.

In a salinity refractometer, 35 ppt = 1.0264 SG

Correct, I meant straight across from each other.

I assumed the left side was salinity, and have been going by that forever.