Highlight TVI Not Accurate in Profile
Greetings, FYI - I recently posted this to Print Planet. I am a flexo printer and have created a profile using iProfiler for a poly stock which has a very high TVI. In order to make an accurate proof I had to build what I would call, an extreme gradation in my CGS proofing workflow, which led me to believe the profile is not accurately reporting my highlight TVI. I checked the TVI on press sheet with a 530; in ColorAnt using the measurement file; and, in ColorThink using the profile. ColorAnt matches the TVI in highlights that the press printed, but the profile in ColorThink does not. Here is the data for cyan: 1.96%: ColorAnt 26% Press 24% ColorThink 7% @1%, 13% @2% 2.75%: ColorAnt 30% Press 29% ColorThink 14% @2%, 20% @3% 4.71%: ColorAnt 36% Press 35% ColorThink 27% @4%, 32% @5% I have had some feedback as to why this is happening, but would appreciate some more. Additionally, is editing the profile in something like Profile Editor, which I still own, the only way to fix this. In my limited experience using iProfiler I do not see a way to make edits such as these to a profile. Thanks. -Bill-
On May 29, 2014, at 8:42 AM, William Whitfield <billw@mlode.com> wrote:
Greetings,
FYI - I recently posted this to Print Planet. I am a flexo printer and have created a profile using iProfiler for a poly stock which has a very high TVI. In order to make an accurate proof I had to build what I would call, an extreme gradation in my CGS proofing workflow, which led me to believe the profile is not accurately reporting my highlight TVI.
I checked the TVI on press sheet with a 530; in ColorAnt using the measurement file; and, in ColorThink using the profile. ColorAnt matches the TVI in highlights that the press printed, but the profile in ColorThink does not. Here is the data for cyan:
Hi Bill! TVI reported from a profile is not the same as TVI using actual density values (which the 530 and calculations from the spectral values in measurement files will give you). I don’t want to get into an argument about which method is more or less valid (though I’m more likely to rely on density based myself) The simple fact is that we only have colorimetric information available in profiles and so we are left with using the XYZ method outlined on Lindbloom’s site. It has proven to be a fairly effective estimation and is becoming a popular method of calculating TVI but it can give different results. That said, perhaps the profile really is differing from where it should be. If you send it to me I’ll take a look. regards, Steve
read more about the background here: You don't know the difference between colorimetrical and densitometrical tone value? http://www.fogra.org/en/fogra-research/prepress/expert-knowledge/expert-know... regards Andy PS: Please avoid any densitometrical assessments for characterising colour in digital imaging systems (it is still very appropriate for process control). On 29 May 2014, at 20:11, Steve Upton <upton@chromix.com> wrote:
On May 29, 2014, at 8:42 AM, William Whitfield <billw@mlode.com> wrote:
Greetings,
FYI - I recently posted this to Print Planet. I am a flexo printer and have created a profile using iProfiler for a poly stock which has a very high TVI. In order to make an accurate proof I had to build what I would call, an extreme gradation in my CGS proofing workflow, which led me to believe the profile is not accurately reporting my highlight TVI.
I checked the TVI on press sheet with a 530; in ColorAnt using the measurement file; and, in ColorThink using the profile. ColorAnt matches the TVI in highlights that the press printed, but the profile in ColorThink does not. Here is the data for cyan:
Hi Bill!
TVI reported from a profile is not the same as TVI using actual density values (which the 530 and calculations from the spectral values in measurement files will give you).
I don’t want to get into an argument about which method is more or less valid (though I’m more likely to rely on density based myself)
The simple fact is that we only have colorimetric information available in profiles and so we are left with using the XYZ method outlined on Lindbloom’s site. It has proven to be a fairly effective estimation and is becoming a popular method of calculating TVI but it can give different results.
That said, perhaps the profile really is differing from where it should be. If you send it to me I’ll take a look.
regards,
Steve
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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hello William and List, This is probably not only the case between of different tvi calculations, but also an issue of smoothing flexo highlights during the ICC profile calculation. By the way, the extremly high TVI (26%) for 1,96% is an indicator, that there is optimization potential in your flexo plate making process and may be also in the combination of flexo plate and anilox rollers. Modern rasterization technologies and optimized compensation curves for flexo platemaking should lead to a lower TVI at 1,96 % You may should have also a look at colorlogic CoPrA3 for ICC profile generation, which has some nice features for calculating ICC-profiles for flexoptinting. See e.g: http://www.colorlogic.de/help/?p=3473&lang=en Best regards Jan-Peter Am 29.05.14 17:42, schrieb William Whitfield:
Greetings,
FYI - I recently posted this to Print Planet. I am a flexo printer and have created a profile using iProfiler for a poly stock which has a very high TVI. In order to make an accurate proof I had to build what I would call, an extreme gradation in my CGS proofing workflow, which led me to believe the profile is not accurately reporting my highlight TVI.
I checked the TVI on press sheet with a 530; in ColorAnt using the measurement file; and, in ColorThink using the profile. ColorAnt matches the TVI in highlights that the press printed, but the profile in ColorThink does not. Here is the data for cyan:
1.96%: ColorAnt 26% Press 24% ColorThink 7% @1%, 13% @2%
2.75%: ColorAnt 30% Press 29% ColorThink 14% @2%, 20% @3%
4.71%: ColorAnt 36% Press 35% ColorThink 27% @4%, 32% @5%
I have had some feedback as to why this is happening, but would appreciate some more. Additionally, is editing the profile in something like Profile Editor, which I still own, the only way to fix this. In my limited experience using iProfiler I do not see a way to make edits such as these to a profile.
Thanks.
-Bill-
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participants (4)
-
Andreas Kraushaar
-
Jan-Peter Homann
-
Steve Upton
-
William Whitfield