Hi Everyone. I'm reasonably new to home brewing and am gradually increasing my knowledge and trying to upgrade my techniques. I would like to have a far quicker way of measuring pre-boil SG and I bought a refractometer and have now calculated the 'Wort Corrective Factor' as 1.0229 from measuring 5 different worts 5 times with it and my hydrometer (as per instructions on various sites). However, I'm not quite sure what I do with the 'Correction Factor'! I assume that I read the BRIX on the refractometer then divide (or multiply?) it by the 'Correction Factor' to give me a corrected Brix reading then convert Brix to SG? Can anyone help? Many thanks. Mark

Sounds like you have it figured out. Read the Brix, multiply by the wort correction factor, then convert to SG.

You can also add it into the equipment profile here so that if you're using the brew sessions feature it will apply the correction factor for you (haven't tried that myself).

To the best of my knowledge, my refractometer gives me a straight up gravity reading... I haven't been doing any corrections to the readings.

I use it throughout fermentation - far lower samples, I can keep track of how things are going and with the correction, it's as accurate as my hydrometer. Far easier to read, too.

Thanks for this. So I multiply rather than divide the BRIX reading by the correction factor yes? Much appreciated

Yes, for a super quick estimate on the fly, just multiply by four. If the refractometer has 14.8, the estimated brix is 59 (1.0592). Then, when you have a moment, use the calculator with the correction factor in it: https://www.brewersfriend.com/refractometer-calculator/ For info: https://www.brewersfriend.com/2013/...rrectly-for-maximum-accuracy-in-home-brewing/

my refractometer has an SG scale on it, do I need to make any corrections? Maybe next brew Iwill do both and confirm the readings

You won't need to correct if your refractometer already has an SG scale. If it is in Brix, it's a wine refractometer and you need the corrections. If it's in SG, it's made for beer and the scale is already corrected. I use the correction factor in the equations to convert from SG to Plato when I'm correcting the beer for alcohol as well.

There are equations you can use to correct it. This site has a calculator that employs one: You enter the original gravity and the refractometer reading, as well as your refractometer correction factor, and it converts the reading to SG, You're right that the actual reading is inaccurate but it can be corrected. The correction equations used here and in a past issue of Zymurgy are accurate on FG to the point where I can't tell the difference at 3 decimal points between my finishing hydrometer and my refractometer.

I gotcha now. I thought it was like a calibration to ensure overall accuracy. Thanks for the clarification.