[yso191]

I recently purchased a set of 3 narrow-range, laboratory-grade hydrometers from Northern Brewer for ~$60.  I love the idea of greater accuracy, and easier to read Hydrometers.

I brewed yesterday.  I checked the OG three ways.  My refractometer said 1.085; the old standard hydrometer said the same.  The new 'lab grade' hydrometer read 1.080.

So I got some distilled water and the low range 'lab grade' hydrometer.  It read 0.999.  The old regular hydrometer read 1.000, as did the refractometer.

I'll do a test on the other two Hydrometers with some sugar water of a known gravity, but so far I am unimpressed.

[hopfenundmalz]

It is like having 2 clocks, whichis right.

Read up on making your known solution of sugar water. You can dilute to make it half the %, then half again easily.

The lab grade was off .01 with water, so the 0 is off a know amount. The difference with the old hydrometer and the refractometer was bigger, so there is a gain difference somewhere.

Keep us posted on what you find. I need to do the same someday soom.

[yso191]

Here's what I came up with:

In a 1.085 solution:
The refractometer showed 1.085
The high range hydrometer showed 1.083  (I suspect yesterday's reading below was incorrect)
The full range hydrometer showed 1.082

In a 1.040 solution:
The refractometer showed 1.041
The mid-range hydrometer showed 1.041
The full range hydrometer showed 1.041

In RO water:
The refractometer showed 0.000
The low range hydrometer showed 0.999
The full range hydrometer showed 0.000

The bottom line for me is that when measuring OG I am going to stick with the refractometer.  When measuring FG I'll go with the low range hydrometer just because it is easier to read, and adjust up 0.001.
I love being exact, but it is homebrew so no big deal either way I'm sure.

[hopfenundmalz]

Here's what I came up with:

In a 1.085 solution:
The refractometer showed 1.085
The high range hydrometer showed 1.083  (I suspect yesterday's reading below was incorrect)
The full range hydrometer showed 1.082

In a 1.040 solution:
The refractometer showed 1.041
The mid-range hydrometer showed 1.041
The full range hydrometer showed 1.041

In RO water:
The refractometer showed 0.000
The low range hydrometer showed 0.999
The full range hydrometer showed 0.000

The bottom line for me is that when measuring OG I am going to stick with the refractometer.  When measuring FG I'll go with the low range hydrometer just because it is easier to read, and adjust up 0.001.
I love being exact, but it is homebrew so no big deal either way I'm sure.

Thanks. Have to do that someday.

Also for a scale I suspect at low mass, and a TDS meter just to check it.

[S. cerevisiae]

At what temperature did you take your readings? Density varies with temperature.  Hydrometers are calibrated to read 1.0 with distilled water at a specified temperature. Your hydrometers should have shipped with slips of paper that give you a list of temperature corrections.