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Re: [SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of products

Re: [SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of products

2007-10-19 by Jan Barkan

What is L Star curve mean exactly?
----- Original Message -----
Show quoted textHide quoted text
Sent: Friday, October 19, 2007 7:27 AM
Subject: [SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of products

>>I assume you are referring to curve-creation ability in Spyder2PRO.

No, I was referring to importing a curve, not creating one...

>>Could you provide a good L-Star curve preset?

Yes, Spyder3Elite does exactly that...

I'm sure it would be appreciaged
by some of
the current PFP + Spyder2 users.

Sorry, we aren't building new features into the older products. We have
just recently licensed L-Star, and are adding into our new line of
products.

C. David Tobie
Product Technology Manager
ColorVision, Inc.
CDTobie@colorvision.com
www.colorvision.com

-----Original Message-----
From: marko.mili <marko.mili@gmail.com>
To: colorvision_group@yahoogroups.com
Sent: Thu, 18 Oct 2007 5:58 am
Subject: [colorvision_group] Re: Initial info on the new Spyder3 line
of products

--- In colorvision_group@yahoogroups.com, CDTobie@... wrote:
> Actually you can load any tone response curve into Spyder2PRO,
> including L-Star, if you have a copy of it. Its just built in with
> Spyder3Elite, so that its an internal choice, not something that
> requires an external curve.

David,

I assume you are referring to curve-creation ability in Spyder2PRO. Do
you think
9-point
curve is adequate to effectively describe L-Star? What better tool can
be used
to create more
fitted curve - it appears that documents in Curve folder are a
variation on .icc
files. Can these
files only contain curves with points or can you read parametric curves
like in
ICC v4?

Could you provide a good L-Star curve preset? I'm sure it would be
appreciaged
by some of
the current PFP + Spyder2 users.

Cheers.

Yahoo! Groups Links

__________________________________________________________
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[SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of prod

2007-10-19 by marko.mili

--- In colorvision_group@yahoogroups.com, Jan Barkan <jbarkan@...> wrote:
>
> What is L Star curve mean exactly?

Here are a couple of links to get you started:

http://www.colormanagement.org/en/workingspaces.html
http://www.auspiciousdragon.net/photowords/?p=414
http://www.adobeforums.com/cgi-bin/webx?14@@.3bc19316/4
http://photo.net/bboard/q-and-a-fetch-msg?msg_id=00HhKU

basically, instead of using a simple response curve that can be
described by a single gamma value, it uses a slightly different curve
so that RGB values are proportional to visually perceived change in
lightness - at least that is my understanding.

[SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of prod

2007-10-19 by marko.mili

--- In colorvision_group@yahoogroups.com, "J Bryan Kramer"
<codeburner@...> wrote:
>
> From reading thru those links it seems that there is no advantage to
using
> L-star unless you are working in 8 bits. And working in 8 bits would
seem to
> be an odd plan for someone who is worried about color space issues and
> reading this list.
> 
> BK

My understanding of color theory and implementation of color
management is admittedly limited, but I don't think that statement is
entirely true. I realize that in 16 bits quantization errors are not
really an issue for any commonly used color space, but display on my
screen definitely changes when I use gamma 1.8 vs gamma 2.2, even when
looking at color managed images in Photoshop or Lightroom. It
certainly changes non-color managed portions of the display, so
perhaps my perception of what is light and dark inside a color managed
application is affected by that. In any case, I always felt that
shadows are blocked in 2.2 and that everything is too light in 1.8, so
I was hoping L-star would help with that.

Re: [SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of products

2007-10-20 by CDTobie@aol.com

>>What is L Star curve mean exactly?

Its a different way to define the ramp from black to white. Instead of 
following a simply mathematical gamma curve, its tries to more 
accurately imitate the luminance response of the human eye by using a 
more complex curve, based on the L* ramp, such as in L*a*b*...

C. David Tobie
Product Technology Manager
ColorVision, Inc.
CDTobie@...
www.colorvision.com
Show quoted textHide quoted text
-----Original Message-----
From: Jan Barkan <jbarkan@...>
To: colorvision_group@yahoogroups.com
Sent: Fri, 19 Oct 2007 8:33 am
Subject: Re: [SPAM]  Re: [colorvision_group] Re: Initial info on the 
new Spyder3 line of products

















What is L Star curve mean
exactly?

  ----- Original Message -----
  From:
  CDTobie@...

  To: colorvision_group@yahoogroups.com

  Sent: Friday, October 19, 2007 7:27
  AM
  Subject: [SPAM] Re: [colorvision_group]
  Re: Initial info on the new Spyder3 line of products



  >>I assume you are referring to curve-creation ability in
  Spyder2PRO.

No, I was referring to importing a curve, not creating
  one...

>>Could you provide a good L-Star curve
  preset?

Yes, Spyder3Elite does exactly that...

I'm sure it would
  be appreciaged
by some of
the current PFP + Spyder2 users.

Sorry,
  we aren't building new features into the older products. We have
just
  recently licensed L-Star, and are adding into our new line of

products.

C. David Tobie
Product Technology
  Manager
ColorVision, Inc.
CDTobie@...
www.colorvision.com

-----Original
  Message-----
From: marko.mili <marko.mili@...>
To:
  colorvision_group@yahoogroups.com
Sent:
  Thu, 18 Oct 2007 5:58 am
Subject: [colorvision_group] Re: Initial info
  on the new Spyder3 line
of products

--- In colorvision_group@yahoogroups.com,
  CDTobie@... wrote:
> Actually you can load any tone response curve into
  Spyder2PRO,
> including L-Star, if you have a copy of it. Its just built
  in with
> Spyder3Elite, so that its an internal choice, not something
  that
> requires an external curve.

David,

I assume you are
  referring to curve-creation ability in Spyder2PRO. Do
you
  think
9-point
curve is adequate to effectively describe L-Star? What
  better tool can
be used
to create more
fitted curve - it appears
  that documents in Curve folder are a
variation on .icc
files. Can
  these
files only contain curves with points or can you read parametric
  curves
like in
ICC v4?

Could you provide a good L-Star curve
  preset? I'm sure it would be
appreciaged
by some of
the current PFP
  + Spyder2 users.

Cheers.

Yahoo! Groups
  Links

__________________________________________________________
Email
  and AIM finally together. You've gotta check out free AOL Mail! -
http://mail.aol.com








________________________________________________________________________
Email and AIM finally together. You've gotta check out free AOL Mail! - 
http://mail.aol.com

Re: [SPAM] Re: [colorvision_group] Re: Initial info on the new Spyder3 line of prod

2007-10-20 by CDTobie@aol.com

>>In any case, I always felt that
shadows are blocked in 2.2 and that everything is too light in 1.8, so
I was hoping L-star would help with that.

Thats sounds about right...

C. David Tobie
Product Technology Manager
ColorVision, Inc.
CDTobie@...
www.colorvision.com
Show quoted textHide quoted text
-----Original Message-----
From: marko.mili <marko.mili@...>
To: colorvision_group@yahoogroups.com
Sent: Fri, 19 Oct 2007 6:01 pm
Subject: [SPAM] Re: [colorvision_group] Re: Initial info on the new 
Spyder3 line of prod






--- In colorvision_group@yahoogroups.com, "J Bryan Kramer"
<codeburner@...> wrote:
>
> From reading thru those links it seems that there is no advantage to
using
> L-star unless you are working in 8 bits. And working in 8 bits would
seem to
> be an odd plan for someone who is worried about color space issues and
> reading this list.
>
> BK

My understanding of color theory and implementation of color
management is admittedly limited, but I don't think that statement is
entirely true. I realize that in 16 bits quantization errors are not
really an issue for any commonly used color space, but display on my
screen definitely changes when I use gamma 1.8 vs gamma 2.2, even when
looking at color managed images in Photoshop or Lightroom. It
certainly changes non-color managed portions of the display, so
perhaps my perception of what is light and dark inside a color managed
application is affected by that. In any case, I always felt that
shadows are blocked in 2.2 and that everything is too light in 1.8, so
I was hoping L-star would help with that.





Yahoo! Groups Links







________________________________________________________________________
Email and AIM finally together. You've gotta check out free AOL Mail! - 
http://mail.aol.com

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