HomeRoast Digest


Topic: Agtron (can of worms) Match to Pantone? (6 msgs / 181 lines)
1) From: Michael Wade
MiKe:
Anybody ever try matching the Agtron tiles up to Pantone colors?
They're the defacto standard for defining printed colors in graphic design. 
Full sets may not be much cheaper than the Agtron tiles, but since the 
graphic designers I work with have them laying around, thought I'd ask.
Michael Wade

2) From: Dan Bollinger
<Snip>
Pantone, or Pantone Matching System (PMS), is indeed used for graphic design, 
but only for print press using standard printing inks. The problem with that 
color system is that in can only describe colors reproducible using that 
self-imposed and limited color range. That is, it cannot define colors outside 
that range or those falling between the basic colors it uses.
Systems like Munsell can define any color in nature (and beyond), including 
those encompassed by other systems like PMS.
I would not use PMS for this purpose.  The only reason to attempt to use PMS for 
roast colors is if you want to print them on, say, a poster.
Dan

3) From: Michael Wade
While I'm sure that there are other color definition systems that might 
theoretically be more appropriate, the Pantone chips define a great many 
colors, and are quality controlled for consistency, probably much more so 
than paint chips.  If the Pantone system happens to contain color shades 
that correspond closely to the Agtron series, who cares that they were 
designed to describe the end result of specific inks on specific paper 
stock?
My point is that the tool you own beats the pants off some theoretically 
perfect tool...
So back to my question, has anyone ever attempted to find Pantone shades 
that match the Agtron tiles?
Michael Wade

4) From: raymanowen
I agree, the Pantone color matching system exists already and is in much
wider use. Those Agtron color tiles are dedicated only to comparison with
roasted coffee samples, so that system uses fewer color patches. The
relatively few tiles can match "old school" roast gradations to a fine
degree, while allowing the coffee roasting artisan the license to
interpolate his roast level with the available tiles.
Please don't tell me that a roaster is going to sample a few beans with his
trier, cool them to halt their roasting, plunk them onto the
spectrophotometer's sample target after he's zeroed the instrument, take a
reading, compare all the spectral amplitudes with his desired amplitudes.
Then he'd better vacuum the beans out of his spectrophotometer- The roaster
has been progressing all this time - destination, Hell!
There is no time out period in roasting where you can do a precision
measurement while you stop controlling the roast. Only in a primate habitat
would the spectrophotometer itself be kept in a non-clean room environment.
Roasting fumes would poison the optics and sensor in seconds if the
instrument were handy to the roaster. If it's not handy, what's the point?
I have never actually used any spectrophotometer, just observed the
operation so that I could repair or recalibrate the instruments as
necessary. The Analytical Lab had a second airlock, and the Perkin-Elmer AA
(Atomic Absorption Spectrophotometer) was on a marble column that extended
down to bedrock to keep the optics stable.
The care necessary to maintain an obsolete instrument that is still being
milked for Nine Big is ludicrous in a coffee roasting environment. If
somebody knows better, I hope so- but don't quote some pseudo-scientific
obfuscation as support. Nice idea, but does anybody actually benefit from
the obsolescence? Do the Probat or Diedrich operators do it?
Cheers -RayO, aka Opa!
"The indisputable truth is that no coffee is fresh if it isn't fresh
roasted." - - Martin Diedrich

5) From: miKe mcKoffee
This is a multi-part message in MIME format.
Thinking in terms of a single roast batch, sure an Agtron spectrophotometer
may have limited if any usefulness. Thinking in terms of developing and
analyzing a profile for successive precisely profiled batches of the same
bean/blend in a commercial environment on the other hand is another story.
And then lets add replicating the same Head Roast Master developed roast
profile same bean/blend at one of your other roast operations on the other
side of the country that has the same roasting and analyzing equipment.
 
Kona Kurmudgeon miKe mcKoffee
URL to Rosto mods, FrankenFormer, some recipes etc:http://mdmint.home.comcast.net/coffee/Rosto_mod.htmUltimately the quest for Koffee Nirvana is a solitary path. To know I must
first not know. And in knowing know I know not. Each Personal enlightenment
found exploring the many divergent foot steps of Those who have gone before.
Sweet Maria's List - Searchable Archiveshttp://themeyers.org/HomeRoast/ 
From: homeroast-admin
[mailto:homeroast-admin] On Behalf Of
raymanowen
Sent: Saturday, January 20, 2007 11:20 AM
I agree, the Pantone color matching system exists already and is in much
wider use. Those Agtron color tiles are dedicated only to comparison with
roasted coffee samples, so that system uses fewer color patches. The
relatively few tiles can match "old school" roast gradations to a fine
degree, while allowing the coffee roasting artisan the license to
interpolate his roast level with the available tiles. 
Please don't tell me that a roaster is going to sample a few beans with his
trier, cool them to halt their roasting, plunk them onto the
spectrophotometer's sample target after he's zeroed the instrument, take a
reading, compare all the spectral amplitudes with his desired amplitudes.
Then he'd better vacuum the beans out of his spectrophotometer- The roaster
has been progressing all this time - destination, Hell! 
There is no time out period in roasting where you can do a precision
measurement while you stop controlling the roast. Only in a primate habitat
would the spectrophotometer itself be kept in a non-clean room environment.
Roasting fumes would poison the optics and sensor in seconds if the
instrument were handy to the roaster. If it's not handy, what's the point? 
I have never actually used any spectrophotometer, just observed the
operation so that I could repair or recalibrate the instruments as
necessary. The Analytical Lab had a second airlock, and the Perkin-Elmer AA
(Atomic Absorption Spectrophotometer) was on a marble column that extended
down to bedrock to keep the optics stable. 
The care necessary to maintain an obsolete instrument that is still being
milked for Nine Big is ludicrous in a coffee roasting environment. If
somebody knows better, I hope so- but don't quote some pseudo-scientific
obfuscation as support. Nice idea, but does anybody actually benefit from
the obsolescence? Do the Probat or Diedrich operators do it? 
Cheers -RayO, aka Opa!
"The indisputable truth is that no coffee is fresh if it isn't fresh
roasted." - - Martin Diedrich 

6) From: raymanowen
The atmospheric pressure, relative humidity and bean ambient temperature in
different locations are insignificant. And all these Tons of beans roast
exactly the same. Just set the pointer and push GO. Does that actually work?
-ro
Are they taking applications? Get me off Coffee Stamps!


HomeRoast Digest