It looks like the Beer Bug is looking for supporters of their Digital Hydrometer. They have some updated videos on their www.beerbug.com and http://www.kickstarter.com/projects/parasitx/the-beerbugtm-digital-hydrometer site showing more detailed info about the device.
Looks like a refractometer is much simpler to me.
Isn’t a refractometer only effective for getting OG? The Beer Bug is designed to monitor constantly during fermentation.
You can use a refract to get FG you just need to apply some correction factors to the reading. This is because, If I recall, the refractive index of sugar and alcahol are similar so the refractometer can’t distinguish when alcahol and sugare are both present.
Sean Terril has a good calculator for this on his site.
I use Sean’s calculator and it works very well.
Paul
Glad it’s working out for you guys. Here’s the direct link to the calculator: Refractometer Calculator « SeanTerrill.com There’s also a spreadsheet you can download to track multiple batches.
It has nothing to do with how similar they are, it is just that they are both non-zero.
I recommend Sean’s calculator too.
what is the wort correction factor and how do i know if i need to change it?
Just use the calculator at Refractometer Calculator « SeanTerrill.com