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rogerB
07-29-2010, 06:55 PM
My first post here -- be gentled.

On Page 5 of ColorFlow UserGuide, the concept of a color setup is explained.

I understand the idea of a PCO, an SCO and a CI.

The PCO is described as "a color reference point to which all other devices in the color setup will be aligned".

As I'm new in ColorFlow's scheme of things, the way I read the above sentence would seem to apply MORE to the idea of a Color Input -- not a PCO.

It seems that having everything gravitate around a PCO (always a press, by definition) is missing the fact that what a print shop should gravitate around is what "standard" or "specification" it is trying to emulate, such as SWOP or GRACoL or ISO-12647-X. Not a press?

Best / RogerB

david.herder
07-29-2010, 07:39 PM
Hi Roger,
By all means, a PCO can be a Press aimed at a spec or standard. A PCO can also be a proofer aimed at a spec or standard. A PCO can also be a spec or standard all by itself.

Some of the disadvantages of adding a CMYK Reference as a PCO are discussed in the OLH, Chapter 4> Working With ColorFlow Software> Aligning a reference device condition in the PCO.

The advantage of using a CMYK reference as your PCO includes simplicity, and overall adherence to the specification as your common "stake in the ground". However, what happens when one device cannot achieve the spec, or there are significant gamut restrictions of one of the SCOs but not others?

Choosing your PCO device condition is the most influential decision that you will make in this software. When you choose the device to add, think about "what color response am I actually selling to my customers?" Is it a press sheet aligned to a spec? A proof? Or, an abstract color response?

hope this helps,
dave

rogerB
07-29-2010, 07:58 PM
I think "it is a press sheet aligned to a spec" -- no doubt.

Silly me, though. In my early endeavours while trying to create new Color Setups, it seems I could not drag a CMYK Reference inside the color setup viewer area -- it only accepted printing presses?

Right now, I was able to click on the "+" button, to create a new color setup, and was able, to drag in the CMYK Reference icon, which I find is a more logical and more explicit starting point.

Yet, when the color setup viewer is empty, there is a message in the background which states "Drag a device here to make a PCO". Which is not totally unintuitive but I better understand, now, why you say thjat any CMYK Reference or Press or Proofer can be dragged inside the window to make a PCO.

It's just that, in my own twisted logic, when dragging a CMYK Reference inside a bare color setup viewer window, I would think that what I'm dragging (my intent) is to create a Color Input -- and not a PCO.

I'll have to wrap my head around this "limitation" -- it's a design choice. But it would seem that the concept of color setup is not about having some Color Input as the thing around which all devices gravitate.

Oh well, we'll see where that leads me.

/ RogerB

david.herder
07-29-2010, 08:09 PM
I understand your logic. If you know what space your input files are in, then it may make more sense to add a CI first, from a design perspective. However, I find that most really have no idea what CMYK they are receiving. In this case, you would only make this determination after you looked at some separations. Therefore, adding a CI later would make sense.

If you're really lucky, you have files coming in with assigned cmyk ICC profiles that reflect the CMYK working space of the input file. With this information, you can choose to either honor the tagged profile, get rid of it, or get rid of it and apply your own CI.

cheers,
dave

rogerB
07-29-2010, 09:21 PM
Yes, if we know what color space the files are coming in, yes, in that case, it makes sense to want to have a Color Input reflect that state of affair. But when mystery meat comes in the door, then, I can see your logic. Albeit at some point, we'll have to make an assumption, an intelligent decision, either assume everything belongs to SWOP__Cx or GRACoL_Cx or something else, but a Source has to be defined in order to carry the rest of the processing off. But, it will be interesting to use embedded profiles, as some clients follow strictly our guidance, as far as color is concerned.

Thank's / Roger

andy.woolcott
07-30-2010, 09:57 AM
Kind of on the same note, why does Prinergy remove the Output intent identifier after refine or if using a CI in Colourflow?
I did some testing with files with Output intents applied and some without, and although Prinergy recognized the ones with (refine info notes), if after refine you perform a preflight the file has no output intent anymore.

Any thoughts?

rogerB
07-30-2010, 01:18 PM
I found out the same thing too, although it has nothing to do with ColorFlow since that undesirable behabior was in 4.x. This is most inconsistent, IMO, with any PDF standardization efforts on the part of the industry : what is the reason for doing such a barbarian surgery? Talk about loss of information...

Roger

david.herder
08-04-2010, 07:03 PM
I guess the logic "if you don't use it, you lose it" applies here. The output intent is supposed to be used as a separation space for the digital master. So, it stands to reason that if it is not used, you have chosen to refine to some other output color space. Thus, it is removed in favour of your destination separation space.