Correct Sg Temperature

[Darren]

My hydrometer's correction chart is approximately 0.001 for every 5 degrees, which seems to correlate with the values in the wikipedia entry. The chart I posted only covers up to 15, and my hydro's table only covers down to 15, and judging from the curve I think it's reasonable to assume the slope grows stronger.

Since I'm supposed to be writing rather than posting here, I charted the wikipedia data. It's more illuminating than the other chart I found:

View attachment 5386

[post="101022"][/post]​

Funny. I though it was more than that but you are right. Hardly seems worrying about considering the angle of paralax and the meniscus could easily count for for than that anyhow.

cheers
Darren

 

[Kai]

Yes, I rarely worry about it. Equipment and measuring error would more than override it in most cases, I think.

 

[Gulf Brewery]

Does anyone using a refractometer lower their sample temperature a bit before adding your drop to the refractometer?

<snip>
Cheers, Justin

[post="100956"][/post]​

Justin

It definitely does occur even in microbreweries. Brad and I have proved it several times that the readings are out, especially when the wort is nearly boiling. From memory I thought the readings were lower when the wort was very hot.

We cool a sample and then read and I am using the same model refractometer as Darren

Cheers
Pedro

 

[Kai]

Just curiosity, because I don't think it matters; does darren have one with automatic temp-correction?