DIY Photometer for EBC measurement

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WishboneBrewery
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Re: DIY Photometer for EBC measurement

Post by WishboneBrewery » Thu Jun 16, 2011 8:32 pm

Horatio wrote:Love it! People like you make the world a greater place. :D
"Greater" = Geek / Nerd / Techie :)

andybiochem

Re: DIY Photometer for EBC measurement

Post by andybiochem » Fri Jun 17, 2011 9:42 am

Right the software is available HERE.

Let me know if you manage to get any use out of it! In fact post some photos...showing how wildly inaccurate it is!! :lol:

Brew day today, so I'll post a shot of it in action once the wort is ready.

Birdman

Re: DIY Photometer for EBC measurement

Post by Birdman » Fri Jun 17, 2011 10:59 pm

Brilliant!!

I'm meant to be a scientist for a living, but you seem to have done more actual science in a few days than I have in the last few years...

andybiochem

Re: DIY Photometer for EBC measurement

Post by andybiochem » Sat Jun 18, 2011 11:04 am

Birdman wrote:Brilliant!!

I'm meant to be a scientist for a living, but you seem to have done more actual science in a few days than I have in the last few years...
Haha! Don't worry, I'm a professional scientist too!

andybiochem

Re: DIY Photometer for EBC measurement

Post by andybiochem » Sat Jun 18, 2011 1:00 pm

Here is the reading of yesterday's brew.

It was a particularly dark stout, BeerSmith said it would end up as 106.4 EBC.

Image


Now, because it is such a dark beer and as we've seen the ability of the software to distinguish darker beers is quite poor (evident from the standard curve), I decided to dilute the target beer to bring it into a useful colour range. Apparently it is standard approach to dilute dark beers before colour measurment.


Here's a screen shot:
Image

Note that I used the original uneditied photo from my iPhone (it came out quite over-exposed), and I added labels in PS afterwards just for clarity.

Looking at the curve produced from the standards, the best looking curve is the "red channel only" so I used that for estimation. Sure enough, the dark end (70 - 100 % on the x axis), is almost flat. This means the software will not pick up any differences in colour for dilutions between 70 - 100 % (i.e. 35 - 50 EBC). It doesn't really recover until below 50% too, so I opted to use the 20% dilution of my target beer for measurement. It came out as 21.9 EBC.

Multiplying 20% back up to 100% gives (21.9 x 5) = 109.5 EBC for this stout, not far off the prediction of 106.4.

This was a measurement of the sweet wort before fermentation, so I'd assume things might be different once fermented and fined (I know, I know, no need to fine stouts, but I do anyway [-X ).

Promising first steps perhaps? [-o< [-o< [-o<

Cheers!

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simple one
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Re: DIY Photometer for EBC measurement

Post by simple one » Tue Jun 28, 2011 10:24 pm

Just found this thread. Very interesting, and thank for sharing your findings. Good work!

kivsaras

Re: DIY Photometer for EBC measurement

Post by kivsaras » Wed Apr 05, 2017 4:30 am

what kind of software you used to measure...may u send me the link...wanna use for school project

Haydnexport
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Re: DIY Photometer for EBC measurement

Post by Haydnexport » Wed Apr 05, 2017 4:27 pm

Holy thread resurrection Batman ! :shock:

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