13

As far as I know, you can determine the final gravity solely with a refractometer only if you know the original gravity (either with a hydrometer or the refractometer). I am a small-batch brewer, and exclusively use a refractometer for gravity measurements. A few tips: You have to calibrate your refractometer to read zero when using distilled water as your ...


8

They are different but only in the scale the refraction is interpreted. You can get refractometers with various scales. Specific Gravity, brix, plato, ppm/ppt (saline). This is a very good question because refractometers don't just read sugar. Anything that affects light refraction will affect the reading. This includes water chemistry adjucts! This is ...


6

They are both very accurate when used correctly. It's really best to use both Refractometer is only accurate for OG readings. Benefit is a few drops for sample instead of 100-200ml. This is very useful when doing several samples trying to hit an OG in the mash/boil process. You still need your hydrometer for fermentation gravity readings and FG. Though ...


6

The July/August 2013 edition (vol 36/no 4) of Zymurgy magazine has the answer. Sean Terrill's article, "Using a Refractometer" pp. 49-53 details pretty much everything you want to know about refractometers in brewing. A two-point calibration is recommended: Water at 0.0°Bx A reference sucrose solution, for example 20.0°Bx (20.0g table sugar in 80.0g water) ...


6

IMHO answer to this question is that the fluid under test is "opaque"and so the reading line is "diffuse". The opaque nature is usually due to yeast being present and it is better to test a clear(er) solution. Sometimes this is down to bubbles but they can usually be cleared by pressing on the sample cover plate.


5

I have found that the refractometer line comes out fuzzy if the transparent lip is not flush with the prism. This can be due to particulates which introduce a distance, CO2 in the solution which creates bubbles or small air pockets. Usually lifting the lip and letting it drop into the sample a couple of times does the trick. Measuring cold fermenting wort at ...


4

Well a refractometer is very accurate for measuring OG. you do have to calibrate it using a wort of known gravity, but once that's done You are good to go with the refractometer. I am equally confident in my refractometer and hydrometer readings. The refractometer is less useful for FG, due to the alcohol present in the solution. There are conversion ...


4

I haven't used a hydrometer in years. I think they are worthless and you waste a fair amount of beer using one. You can do a very close estimate of your alcohol content by just using only a refractometer. I used a similar formula when making wine and remembered it for using it with beer too. I won't post the formula here (it's at this website). I never ...


3

Which of these two tools is more accurate/precise in taking gravity measurements? Hydrometer. In my experiance. It could be my cheap refractometer but i've noticed some inaccurate readings and I therefore don't trust it completely. I use the refractometer during the boil and fermentation just to get a general idea, but always a final reading with a ...


3

The first thing to note is that your refractometer and your hydrometer are measuring different physical attributes of your wort. You need to account for these differences, and additional errors. Refractometers The refractometer is primarily measuring sugar content, through the difference in refraction relative to pure water. This is where calibration comes ...


2

Refractometers are best used for pre-fermentation readings. I use mine to get pre and post boil gravities and then use a hydrometer to check on fermentation. The nice thing about using them on brew day is you only need a few drops which cools much faster than a full hydrometer sample. Many refractometers have automatic temperature correction, and ...


2

As far as I know that's the best way to calibrate it. I keep two pipettes handy on brew day, one for samples and one for calibrating. I re-calibrate before each reading and it usually needs little or no adjustment. Once in a while it will be off quite a bit but I haven't figured out what knocks it out.


2

No. The scales are different. The refractometer works on the principle that when a ray of light crosses a boundary (in this case into a fluid), the material refracts the ray under a certain angle. This is expressed as a number called the refractive index. This index changes depending upon the material. The refractive index of salt water is different from ...


2

Conversion from Brix to SG doesn't require temp adjustment. Only the reading you measure needs to be adjusted for temp. Or better yet zero out your refractometer with distilled water that's the same temp as your wort. Do this easily by letting both the wort and distilled water sit at room temp until even, then calibrate, then take reading. Edit: SG scale ...


2

Both Brix and specific gravity are temperature sensitive but the conversion seems to be independent of that fact. That is, if you start with the correct value in Brix, your converted SG value will be correct. So you will want to make sure that your Brix value is temperature adjusted before you do the conversion. From what I've heard, refractometers ...


2

I recently switched too. One problem I noticed with the smaller sample is that if you pull from the top of the vessle you may get some oils or other less dense particles collected at the top. This layer of particles doesn't effect the hydrometer much reading since the sample size is much larger. Precision - as long as temp is about 70f the hydrometer will ...


2

Refractometers become less accurate once the yeast has started fermenting the sugars into alcohol. It fails to take into account that there is sugar, alcohol, and water in solution, and only measures the sugar and water. That is why you got a different reading. Ending at 1.000 isn't uncommon if you ferment to tolerance, but from what you've said, it sounds ...


1

Simple. The SG scale is wrong. Only use Brix. A refractometer is incapable of measuring SG. It's an approximation, and in this case especially, it's pretty far off. Instead of using that SG scale, use a conversion tool like this, which is way more accurate when done properly, both for OG and FG: https://www.brewersfriend.com/refractometer-calculator/ ...


1

I have used the same wort calculators on ciders with some success. True the ingredients are different, but the correction curves should be similar. Personally for beer-wort I use a correction factor of 0.99 for my refractometer, and 1.04 for cider... but your mileage may vary. You might even find the opposite is true for your refractometer. Each gauge ...


1

If you're measuring FG with a refrac, you need to compensate for alcohol. Alcohol in solution will increase the apparent gravity in a refrac. For this exact reason, I never measure gravity with a refrac after I've pitched yeast.


1

I believe the answers from @Evil Zymurgist and @thesquaregroot have missed the point. Nowadays, for brewers at least, the SG of a sample is conventionally reported as its density relative to water at 20 degrees Centigrade. If the standard was defined at a different temperature then the specific gravity value would most likely be different since the thermal ...


1

It's probably fuzzy because the CO², you may try to transfer the beer from a cup to another, about 20 times, to make it go away, then try to read again. Don't forget to do alcohol correction, using this (or other) calculator (based on OG): https://www.brewersfriend.com/refractometer-calculator/


1

Refractometer are commonly used to measure sugar in grapes before picking them up to make wine, you need less liquid to get a measurement. Less common in homebrewing, but also used, just make sure it has the right scale, but you can convert the value from Plato or Brix scale to SG as well. Other scales? Maybe not... https://en.wikipedia.org/wiki/...


1

Yes, but you have to factor in the alcohol so you'll need a refractometer adjustment calculator. Northern Brewer has one on their website and there are other online calculators as well. But no two calculators seem to agree perfectly. Personally, if I'm in the ballpark I'm happy. But if you want to be certain of getting the most accurate measurement possible ...


1

First, refractometers vary, their quality is different from model to model. Temperature range they can work properly is pretty wide, but it's there. Make sure you are not outside it. Second, with your refractometer you should get manual and calibrating solution. Be sure to use these, without proper calibration readings will be off. Third, of course pre-...


1

I use a small hydrometer (17cm in length) and a 50ml test tube. I rarely need more than 40ml to take a reading, so four readings would require, in total, less than 5% of you wort.


1

I find a refractometer works great for OG, and a finishing hydrometer works best for final gravity (with presence of alcohol). I typically drink the sample, as I am mostly curious as to how the flavor is shaping up, especially once FG has settled (to gauge bulk-aging or conditioning impact on flavor). However, I have some sours that I sometimes return the ...


1

Perhaps, but I have tried this with a couple of online calculators and with brewtarget and each time, the calculated final gravity is significantly lower than my actual hydrometer reading. I finally gave up. I actually find the hydrometer a bit simpler for final gravity anyway. The refractometer with ATC comes in handy with hot first and second runnings and ...


1

To answer the question, you can read a refractometer to 0.25 brix, assuming it's got 0.25 brix calibrations. It's harder to get more accurate than that with the typical handheld refractometer since the lines are quite close together.


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