What's differences between Color Server and Device Link Profile

[sornchai]

Hi.
I'm from Thailand with little knowledge in prepress. Please explain different Thank you so much

 

[Ulrich]

Hi sornchai

short:

A DeviceLink profile is a single profile, a rigid component, so to speak, for a direct conversion of existing CMYK or RGB tonal values into corresponding CMYK or RGB tonal values of the target color space, bypassing a PCS (Profil-Connecting-Space, e.g. Lab ).
Separation characteristics such as the beginning, end and width of black, total ink amount, use of GCR, UCR, UCA are fixed in every devicelink profile and are not variable.
(Unless a correspondingly differently configured "second" or "third" dlp profile is written and saved as such ...)
It can only be used with specially compatible software (e.g. Callas PDF Toolbox, PitStop, mostly workflow RIPs, but not otherwise color management-capable layout programs such as Indesign or QuarkXpress or even Photoshop...)

A good color server is the software that was actually created for handling DeviceLink profiles, which can then work with dynamic profiles to varying degrees, depending on the manufacturer. In practice, for corresponding conversions from color space to color space (but also within the same color space ...), a different separation character such as black beginning, end, width, total color application, use of GCR, UCR, UCA and Rendering Intent can be managed and as Queue can be saved for the exact same reuse.
The DL-profile is rewritten hidden for the user for practically every job for example in ALWAN-CMYK-optimizer...

There are also "color servers" (eg also in the form of modules for a RIP or workflow) that do not have any dynamic functions. Here, rigid dlp profiles are used again, which must be made available to the color server, but in turn can no longer be varied individually (see above). Their authorization arises from the fact that the usual layout, graphics and image processing software usually cannot handle DL-profiles ...

 

[sornchai]

Ulrich.
Clearly.Thank you very much
Take care yourself

 

[Mike Strickler]

Hi.
I'm from Thailand with little knowledge in prepress. Please explain different Thank you so much

Hello Sornchai,

Color servers are essentially standalone applications for converting documents, mostly but not exclusively PDFs, to a target or destination color space to optimize a color match or printability. They are related to color conversion engines in color-managed applications such as photoshop but with special capabilities for converting vector art in addition to images, along with a variety of specialized tools and adjustments. They employ color profiles, and as Ulrich has sated, these include device link profiles. DLPs are normally needed to convert type and other vector objects to preserve pure colors (e.g., in type) and other color combinations. DLPs consist of a source and a destination profile, and rules governing the conversion of color from one color space to another. Besides conversion exemptions, they can flexibly control the separation parameters such as TAC, black or multicolor (ECG) generation, special ink-saving algorithms, and so on, and can override settings in their constituent profiles, if desired. Device links are normally made in a special profiling application, but as Ulrich said, some color servers can build them on the fly while converting a PDF, which allows more flexibility, as each object can be rebuilt with an optimal separation, and multiple source profiles, each embedded in a different object in a single document (assuming PDF-X) can be assigned and used. This is not possible when using a single, fixed device link profile. I would encourage you to look at ColorLogic's ZePrA color server. It is, in my estimation, the most advanced application of this type, by a considerable margin.

Good luck.

Mike