Is there a temp correction for brix?

Most refractometers have automatic temperature correction, but my guess is that 195F would be outside of the effective range.

Maybe try calibrating to 0Bx with a 195F water sample, making sure to calibrate and measure as quickly as possible?

ETA: To answer your question, I've never seen a refractometer temp correction chart/formula.

 

Since you only need a drop of wort for a refract reading, can't you give it 30 secs to cool. Some tricks I have employed to help ensure cooling:

• sample tiny amount of wort with spoon and put something from your freezer on the bottom of spoon to cool it rapidly (Jamil Z offered this trick on a Brewing Network podcast_/
• put tiny amount of sample in a large vessel (I use a ceramic ramekin just because I happen to store them near where I happen to boil, i.e., in my kitchen) for brief cooling

The low thermal mass of the tiny amount of wort you need for this really works in your favor. My guess is even if you put a drop of 195F wort on your refrac, it would be cooled by the larger thermal mass of the refract by the time you get your eyeball aimed at the eyepiece. Still might not be down into the range at which it reads accurately and I would worry that hot liquid can't be good for your instrument. But any temperature correction would need to somehow take this cooling into consideration and I would think that would result in an inaccurate model (unless you have some sort of combination refractometer/thermometer).

 

This topic has never come up at any of the places I've worked at.
I'm far more worried about steam getting into the optics of my refractometer than I am about its being accurate at those temps.
As has been mentioned. A few drops of liquid don't stand a chance at maintaining that kind of temp with all of the handling to get the sample legible on the surface area followed by the length of time it takes to get it to your eyeball.

 

I recommend getting a BRIX hydrometer (ones used in the Maple Syrup industry) and measure your BRIX at the hydro's calibration temp. (typically 60degrees F). From there use the NIST's Table 19 or another chart for calculating.

 

Not really necessary. That is overthinking something that doesn't really require it.
If you want to be thorough. Do both refractometer and hydrometer readings. And make sure your refractometer is calibrated. If you are worried about getting a false reading from one or the other. De-gas what you use for your hydrometer reading. i.e. shake it like a cocktail. And leave your refractometer alone for a couple minutes with a sample in it. Leave them both alone for a few minutes, and read again. C02 is typically the culprit of bad readings.

 

I fill up a shallow ramekin with ice water before I brew.
I then use one of these:
to pull samples and place it in the ice bath to cool. You can also use a shot glass or espresso cup.
I chill because:
I also take ph readings, which DOES require cooler wort unless you want to wait for hours for the meter to autocorrect.
And I don’t just drop a couple drops on the refractometer. I pour over the pane, which seems to produce a better image for me.

 

I believe the temperature autocorrect on a refractometer is to correct for the ambient temperature of the refractometer.

As already been pointed out, a few drops of wort will equilibrate with the surrounding parts of the refrectometer rather quickly.

Personally, I wouldn't put a drop of near-boiling wort on the optics of my (rather pricey) refractometer.

Cheers!

 

If you wear two watches, you'll never know what time it is. Pick one or the other. As long as you use the same device at all stages of the process, you'll get all the data you need in the context of home brewing. Unless you're comparing notes with other brewers, it's the deltas that are significant, not the actual numbers.