DIY Color Meter - Page 73

August 5th, 2023, 4:34 pm

A short video showing the workflow for the new DIY roast meter.

#722: Post by **Grrr** » September 12th, 2023, 7:23 am

Hello Roast Meter family,

I got all the SparkFun parts, compiled and uploaded roast_meter.ino with the added libraries....

Troubles!

I only get a red light on the main board and one on the sensor board, but nothing on the screen.

What am I missing?

G

#723: Post by **yakster** » September 12th, 2023, 5:07 pm

Make sure you don't have any bent pins on the connectors to the display, that happened to me.

#724: Post by **fjen** » October 6th, 2023, 10:00 pm

Transparent Roaster wrote:A short video showing the workflow for the new DIY roast meter.
video

This device look awesome! Did this ever end up open-sourced? If so, would love a Github link!

#725: Post by **yakster** » October 6th, 2023, 11:33 pm

Here's the link to the project, I'm not sure that Transparent Roaster's enclosure style is checked in, I built one using an early version of a rectangular box.

https://github.com/juztins-lab/roast-meter

#726: Post by **seandotsh** » October 16th, 2023, 7:46 am

Picking this thread back up, I built a meter and looked at some of the coffees I have.

I spoke to a local roaster who measure their roasts with a Lighttells, and we compared the two units side by side. The Roast Meter was fairly consistently reading 10-12 points high, with the Roast Meter calibrated to 230 on bicarb as per the instructions.
Now, I can't say I know for sure their Lighttells unit is calibrated correctly, BUT, my intuition with the coffees we were looking at and some of my other coffees at home, was that the roast meter was reading high. Having this "confirmed" by the roaster kind of made sense to me.

Is there evidence / a paper trail for the roast meter having been calibrated directly against another unit like this?

Wondering if it'd be useful to spend some time at the roastery getting numbers from both units and see how they stack up.

I have for now re-calibrated my meter so that the readings on the same coffee from it and the Lighttells match, but equally bicarb can still be used as a universal medium to calibrate - it would just need to drop around 10-12 points or so.

#727: Post by **EricC** » October 16th, 2023, 8:30 am

You can look here : https://discord.com/channels/9455924380 ... 3951501493

This is the original and complete thread for "The Roast Meter" on Discord.

It is located within the Unofficial : Kaffelogic usergroup

#728: Post by **Grrr** » October 16th, 2023, 8:56 am

I get those numbers :

Bicarbonate = 249

Roast Meter = 103

Dipper Color Meter = 101.5

#729: Post by **Grrr** » October 16th, 2023, 9:11 am

EricC wrote:You can look here : https://discord.com/channels/9455924380 ... 3951501493

This is the original and complete thread for "The Roast Meter" on Discord.

It is located within the Unofficial : Kaffelogic usergroup

Your link is not working for me
G

#730: Post by **seandotsh** » October 16th, 2023, 9:18 am

EricC wrote:You can look here : https://discord.com/channels/9455924380 ... 3951501493

This is the original and complete thread for "The Roast Meter" on Discord.

It is located within the Unofficial : Kaffelogic usergroup

Ah that's great thanks Eric!
I wasn't aware of that Discord group, have just joined. I have a lot to catch up on but this thread is exactly what I was interested in so thank you.

Grrr wrote:I get those numbers :
Bicarbonate = 249

Roast Meter = 103

Dipper Color Meter = 101.5

Interesting - you have gone the other way with calibration to me.
Maybe I'm going mad, maybe the roaster / their unit was misreading...!