Ron, I see your point. And I can certainly understand the temptation to get as much value out of the built-in spectro as possible by treating the HP as an automated patch reader, a vey big DTP if you will.
But in order to measure a profile target with the HP you have to associate it with either a new or current paper, which triggers, among other things ink limiting, maximum density and linearity goals. Now if you choose a new/custom paper, the printer will have to output and measure a calibration target. Obviously this can't come from the desktop Epsons. So then you're measuring a profile target whose L numbers may be way way off what the measurment software expects. What would the ramifications be? How well does the on-board profiling software deal with large variations? Because this is in essence a closed profiling system, I don't know.
My instincts (and this is pure speculation) would say that since the HP system is designed around a calibration step which brings printer behavior into a pre-determined optimum state, that there must be a significant benefit as far as the profiling software goes, to receiving data points within a fairly reasonable tolerance range. Third-party profiling solutions are, on the other hand designed expressly for a wide range of inkjet printer models, in various states of performance. IMHO there are too many potential pitfalls in using the on-board profiling software outside of the uses for which it was designed.
Overly cautious? Perhaps. But we've all got years of experience to remind us how tough it can be just to get products to do what they are advertised to do. So I try to keep my expectations for non-supported behavior to a mimumum .
So with the APS, as it currently stands, you cannot simply use the HP printer's spectro to read a target printed by a different printer, and have the software (APS) generate an ICC profile that's independent of some paper and printer-characteristic assumptions being made based on the paper you've told it was used?
I'm being optimistic here, but...
What if you print targets on a 2nd printer. Then you read those targets on the HP, lying to it and telling it that the paper is one of the ones that is already defined in its current repertoire. That way, it doesn't need to print a new set of targets.
Ok, now it reads the existing target from the other printer. Why would the APS need to make any assumptions about the paper characteristics (ink limit, etc.) just to read the targets and generate an ICC profile? It seems to me that those characteristics would be applied when printing the target and not really be relevant when reading the target and generating the ICC profile.
That this profile would, indeed, be useless for the Z3100 would not matter because I'd use that profile with the other printer, printing on THAT printer using the same "paper type" as I'd used when I printed the targets.
Or am I missing some critical piece of the number-crunching that goes into reading a target and generating an ICC profile with APS?
I'm new to all of this and do not own any sort of spectrophotometer or profiling software. So my understanding of this is incomplete. A critical missing piece of my knowledge is: Does a "normal" spectro/profiling system somehow let you enter the paper characteristics (ink limit, base paper tint, etc.) and then mix that data into things when coming up with the ICC profile?
I would have thought not. It seems to me that the job of the profiling program would be to simply measure the patches and compare what it sees against what it expected to see, and thus create a calibration table which would tweak the colors in the file to be printed such that the errors in the printer/paper combination would be compensated. And if that's the case, then it seems as though the APS along with the Z3100 could be fooled into creating an ICC profile which would work for a separate printer.
A previous post to this thread indicates that that poster has used the APS along with a Z printer to do just this. And although they felt that it was no easier to do things this way than to use their other profiling system, there was no indication that the results were bad or faulty in some way.
Since I have no spectrophotometer or profiling program of any sort, it would add a great deal of value to the purchase of a Z3100 and APS if I could do this. It would be my only way of generating profiles for my other printers in-house. So you can see why I'd be interested.
Thanks for reading that long post.