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Author Topic: z3100 HP Technical Newsletter: on Saturated Red  (Read 7086 times)
A. Andrew Gonzalez
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« on: March 14, 2007, 12:34:36 PM »
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https://h41186.www4.hp.com/hpp/Data/printin...s_on_Z31001.pdf
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A. Andrew Gonzalez
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« Reply #1 on: March 14, 2007, 01:45:59 PM »
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Andrew,

Thanks for sharing that link. It appears that HP is taking this forum's comments on the issues as very real and providing great service in the form of new firmware, drivers and Tech Papers.

Jim
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Jim Cole
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« Reply #2 on: March 14, 2007, 04:20:23 PM »
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Best response I have seen from a company re: printer problems.  This alone increases my interest in the Z3100, as HP is obviously taking the term "customer service" seriously.

--John
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Charlie B
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« Reply #3 on: March 14, 2007, 06:27:23 PM »
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Thanks Andrew,

Tried the HP site, though, and evidently the new Mac OSX driver (5.0b.05) is not yet available. Will keep checking. Anyway, it sounds like good news.

Charlie
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Haraldo
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« Reply #4 on: March 15, 2007, 08:46:15 AM »
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Thanks Andrew,

Tried the HP site, though, and evidently the new Mac OSX driver (5.0b.05) is not yet available. Will keep checking. Anyway, it sounds like good news.

Charlie

FYI guys... There was mistake in that last Tech Newsletter (link at top). There is no Mac driver version 5.05b.05 yet. Instead you use the 4.2.1 driver with the 4.1.0.2 firmware. Here's the updated and corrected Tech Newsletter with the correction (dated March 9):

https://h41186.www4.hp.com/Data/printingkno...?pageseq=462046

BTW, the new 4.1.0.2 firmware definitely helped my Reds.

Harald
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Haraldo
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mixwhit
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« Reply #5 on: March 15, 2007, 03:04:19 PM »
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Could someone with a z3100 that saw the red problem confirm that the procedure outlined in this newsletter fixes or doesn't fix the problem?  I'm looking at purchasing a 3100 and am trying to figure out where this issue stands today.
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Panascape
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« Reply #6 on: March 15, 2007, 03:31:16 PM »
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Dark saturated reds are still a problem.
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pcox
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« Reply #7 on: March 15, 2007, 04:42:51 PM »
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Dark saturated reds are still a problem.
[a href=\"index.php?act=findpost&pid=106847\"][{POST_SNAPBACK}][/a]


Yep. This PDF doesn't really say anything new. Its main purpose is to make sure that people are following the correct procedure for using the profiles.

I'm still happy with the output of my 24" Z3100, but the reds could still be improved on.

Cheers,
Peter
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Panascape
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« Reply #8 on: March 15, 2007, 04:59:16 PM »
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This comparison shows the just of what is happening. On the left there is the z3100 and on the right the Epson 4000.

Both printers were loaded with HP Super Heavy Weight Matte. The same test chart was played out on both devices and both charts were read with the z3100's spectrophotometer.

This was done with the new firmware in the z3100 but the paper used was not yet optimised. There has been subsequent changes made and although the z3100 does improve noticeably, the overall situation still shows a problem especially in the areas ringed in red.
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marty m
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« Reply #9 on: March 15, 2007, 08:54:11 PM »
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This comparison shows the just of what is happening. On the left there is the z3100 and on the right the Epson 4000.

Both printers were loaded with HP Super Heavy Weight Matte. The same test chart was played out on both devices and both charts were read with the z3100's spectrophotometer.

This was done with the new firmware in the z3100 but the paper used was not yet optimised. There has been subsequent changes made and although the z3100 does improve noticeably, the overall situation still shows a problem especially in the areas ringed in red.
[a href=\"index.php?act=findpost&pid=106871\"][{POST_SNAPBACK}][/a]

Thanks for actually reporting on what the Z3100 is doing, instead of posting self-congratulatory messages about the wisdom of the great purchase we all made.

The postings that commend HP for being such a great company for this technical newsletter border on self-denial.  That newsletter constitutes an outright denial that there is even a problem, and states that if the printers are properly set-up it can print reds just fine.  Read it carefully.  

Quoting from the newsletter:

"There have been discussions in several forums and through HP’s support organization surrounding the HP Designjet Z3100 Photo Printer series’ ability to print saturated reds. This is, in fact, very possible if you have the right information to get the best out of your printer."

I'll bet that Robert and others are thrilled to know that the failure of their printers to print saturated reds is because they have failed to implement proper procedures "to get the best out of your printer."    The above statement is a flat denial that there is even a problem.  

On the other hand, I strongly agree that HP should be commended for reading this forum, and for responding with tech newsletters based on the comments on this forum.  In point of fact, the newsletter on zebra stripes used an example copied from this forum.  Many companies would not bother to read or respond to forum comments, so HP should be commended for that.  The difference between HP and Canon, in that regard, is night and day.

It is therefore all the more important that forum participants like Robert continue to post their findings, instead of just congratulating HP for turning out a defensive newsletter that essentially denies that there is even a problem even while it acknowledges the reports of the problems.

What we still need is a firmware release that includes all paper types in the driver, especially the generic photo paper.
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Ernst Dinkla
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« Reply #10 on: March 16, 2007, 04:43:27 AM »
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This comparison shows the just of what is happening. On the left there is the z3100 and on the right the Epson 4000.

Both printers were loaded with HP Super Heavy Weight Matte. The same test chart was played out on both devices and both charts were read with the z3100's spectrophotometer.

This was done with the new firmware in the z3100 but the paper used was not yet optimised. There has been subsequent changes made and although the z3100 does improve noticeably, the overall situation still shows a problem especially in the areas ringed in red.
[{POST_SNAPBACK}][/a]

As I understand it you didn't use new media settings because they are not available yet for this paper. Julian Mussi has mentioned the use of other media profiles for a third paper to get a better ink load. An approach that has been used on the Epsons in the past for third party papers not to speak of selecting 1440 or higher dpi settings to get just a bit more ink on the paper (I think HP compensates between lower and higher resolutions ink loads so no extra profiles are needed, the Epson 3800 is at that stage too). I do not not know what the HP Super Heavy Weight Matte can accept but I would suggest to use the (new) Litho-realistic media setting as that one delivers a lot more ink (probably not only ink limits but black generation differences too). The Litho-realistic is 270 gsm so I guess Heavy Weight will pass correctly. Calibrate and profile on Litho realistic, select Heavy Weight in the driver, use the applications CM (Photoshop or Qimage) + the new profile and I wonder what will not fit the Epson 4000 gamut. Also check what you prefer in red green and blue mixes between the Epson 4000 and the Z3100 samples then. There are things that have to be improved but I'm not shy of finding other routes till that is solved. That has been the case with Epsons 3000, 9000, 10000 that I owned before.

Btw, the gamut cuts are a nice representation. A bit more ink and the HP Z3100 stacking order could get different.

Ernst Dinkla

try: [a href=\"http://tech.groups.yahoo.com/group/Wide_Inkjet_Printers/]http://tech.groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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Panascape
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« Reply #11 on: March 16, 2007, 04:51:10 AM »
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Ernst here are the latest plots for HP 8759A - Professional Satin Photo Paper. These tests are being done under controlled conditions and this set uses the latest media profiles from HP.

This new comparison, all though not an orthodox way of doing things, is proving to be very good at highlighting the strong points and weaknesses of both machines. The HP has a far better lighter gamut as shown by the top 5 segments of the chart, a pretty equal mid gamut as per the 5th segment from the top.

If you look at the bottom three segments of the test chart, the red issue is still very prominent even though we have an optimized media profile and this is the paper that is claimed to be giving the best result.  

The bottom three segments are indicating a very big problem for anyone who needs intense saturated and dark colours and clearly shows the red problems.

I have tested all the medias that Julian has and the general pattern is the same. Julian's last apples to apples test shows the same trend.
« Last Edit: March 16, 2007, 04:53:22 AM by Panascape » Logged
Ernst Dinkla
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« Reply #12 on: March 16, 2007, 06:07:02 AM »
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The bottom three segments are indicating a very big problem for anyone who needs intense saturated and dark colours and clearly shows the red problems.

I have tested all the medias that Julian has and the general pattern is the same. Julian's last apples to apples test shows the same trend.
[{POST_SNAPBACK}][/a]

I see the difference, I'm not arguing that outcome. The approach you have is: HP provides me a printer, paper, ink, a profiling solution or profiles, when I use that all I can't get the dark reds/colors of my Epson 4000.

In that case I would tweak, increase ink (can be done in the driver too), use the profiler creation software outside the machine and get the same output of the Epson 4000 for what I have to produce. Is also the best way to find out what could be the reason it doesn't work right out of the box for the HP Z3100. Whether that delivers the best output from the Z3100 is another matter, the Z3100 RGB and  beyond mixes are far cleaner, one wouldn't like to throw that out of the window with less black generation in the media profile for example (in RIP profiling).

So far my solutions to produce larger prints on HPR High White that have to match smaller Epson 4000 prints on EAM/EEM  has been a profile with the Litho-realistic media profile + tweaking the profile in Kodak's editor as the sky blue shifted to cyan where it should be more blue. The Epson 4000 prints + image files are from someone else with a good Eye One profiling package, just coincidence that the samples are from a 4000. Yesterday I made the profile a bit darker too in the curve settings (PS settings for Kodak Custom Color Tools). The HP solution prints lighter in total. It is good now. I have no time to make all kinds of gamut plots but I checked the OEM profile gamuts first in the Wasatch SoftRip 3D profile viewer to see what potentials the media settings have. On that I make the decisions, not going the HP way all the time as I have to match something else. The same I have done to match the prints from the Epson 10000 loaded with MIS7600 ink. I always tweaked the HPR profile of that printer with a -3 green to reduce the metamerism green in cold light. It is inevitable that something has to be done then. That the Z3100 prints are metamerism free and do not need that tweak for that reason is another matter. Right now I'm not even seeking the best Z3100 output possible, there's work to be done that has to match. On 1:1 samples size the Z3100 prints beat the Epson 4000 in image quality.

I have written in another thread what I would like to try out in the HP profiler solution to see whether that delivers profiles that match what I'm used to faster. HP has to provide more new media profiles also. It is printing now though :-)

Ernst Dinkla

try: [a href=\"http://groups.yahoo.com/group/Wide_Inkjet_Printers/]http://groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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Panascape
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« Reply #13 on: March 16, 2007, 06:21:55 AM »
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We are doing the testing comparing the machines under very controlled conditions.

The issues we are seeing is a result of what is coming out of the machine prior to profiling and this cannot be tweaked in the driver or afterwards as you cannot get  machine to lay down more ink thank its paper profile will allow unless you use a different profile which can cause over inking. Also laying down more ink is not always a solution as the z3100 uses complex colour mixing.

HP is busy looking at the colour mixing and a way to improve the results.

"The approach you have is: HP provides me a printer, paper, ink, a profiling solution or profiles, when I use that all I can't get the dark reds/colors of my Epson 4000"

This is certainly not our approach, the tests are being done with three different profiling solutions and hardware so our approach is far more complex and scientific that it may seem and this has meant that we managed to rule the profiling process out as a contributing factor as all three processes generate the same scenario.

Additionally there is more than one of us doing the controlled testing and there is at least one other model of Epson involved.
« Last Edit: March 16, 2007, 06:25:42 AM by Panascape » Logged
neil snape
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« Reply #14 on: March 16, 2007, 08:59:29 AM »
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These slices are a good way to show the strengths and weaknesses in many areas.


This comparison shows the just of what is happening. On the left there is the z3100 and on the right the Epson 4000.

Both printers were loaded with HP Super Heavy Weight Matte. The same test chart was played out on both devices and both charts were read with the z3100's spectrophotometer.

This was done with the new firmware in the z3100 but the paper used was not yet optimised. There has been subsequent changes made and although the z3100 does improve noticeably, the overall situation still shows a problem especially in the areas ringed in red.



Not all media is created alike. Because X printer does better on Y media doesn't say that X printer will not be satisfactory on V paper. The Smooth HP Fine Art  is a lot better at doing reds on the Z than it does on HW matte or off the shelf Hahnemuhle PR for example. The smooth fine art is optimised for these inks , the others are not.
If the media set up can be added and or have a better characterisation for HW matte, then that would be good news for the users of these non optimised  media types.

I'll bet that Robert and others are thrilled to know that the failure of their printers to print saturated reds is because they have failed to implement proper procedures "to get the best out of your printer." The above statement is a flat denial that there is even a problem.

It's easy to see HP have a keen interest in listening to any and all subjects concerning their products. This interest is not only financial, it is also a question of pride and doing the their best. Reports here and from many other sources are both positive, and in infrequent  cases negative.
They take particular notice to the negative comments, as these comments are are the louder of the two types.  Maybe I'm alone in the digital world, but many others also feel the same; we'd rather have a company stand behind their products and continue to improve them as they can. It's quite shocking that certain of you find it incorrect to say the least that HP are indeed working to improve on these and other areas for a released product.
The document , not that I am about to try to find word for word some betrayal, is just about helping users to ensure they do indeed have everything right to get the best they can from their printers.
If you look into the reds on media profiles you'll see gains in reds that bring them back to a point of having good tonal separation, smoothness, and quite saturated in all the L levels that can be improved. Speaking about denial points me back to when I said the Epson K3 inkset, (have any  Epson UC inkset must be even better according to some) will have better dark saturation, especially in reds. I also said that the entire gain in greens, blue greens both of which make the best landscape prints ever seen are colours outside of any Epson printer , the reply was deny anything other than saturated reds.
What seems to be a question of ignorance is thinking that HP eng. have not fully studied their Z printers , nor their competitors products. Absolutely false. Anyone believing this are ignorant or being misled. Anyone thinking that it is a turn of a switch to make an a media setup for a 11 colour/12 ink printer also have little understanding. Working with the given inkset takes time, and  patience on all sides including us the users. The consequences have to be tested fully before they can be made firmware, otherwise the users who may not only seek saturated reds be very dissapointed with all the perfectly good aspects they already have.
Since HP are concerned with trying very hard to get the most out of the problem areas that you are having with reds, it is in good faith you are privy to certain media set ups and or profiles to test. These are all outside of Beta cycles. Do you see any other company working this way ?

It is therefore all the more important that forum participants like Robert continue to post their findings, instead of just congratulating HP for turning out a defensive newsletter that essentially denies that there is even a problem even while it acknowledges the reports of the problems.


While Robert is looking for his reds, HP are helping Robert look for his reds, all of HP are reading this forum to help Robert look for his reds, HP makes a document to help ensure users know how to get what reds they can, you take offense to this. The lat sentence is too far out there to deserve comment.
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neil snape
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« Reply #15 on: March 16, 2007, 09:14:04 AM »
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As I understand it you didn't use new media settings because they are not available yet for this paper. Julian Mussi has mentioned the use of other media profiles for a third paper to get a better ink load. An approach that has been used on the Epsons in the past for third party papers not to speak of selecting 1440 or higher dpi settings to get just a bit more ink on the paper (I think HP compensates between lower and higher resolutions ink loads so no extra profiles are needed, the Epson 3800 is at that stage too). I do not not know what the HP Super Heavy Weight Matte can accept but I would suggest to use the (new) Litho-realistic media setting as that one delivers a lot more ink (probably not only ink limits but black generation differences too). The Litho-realistic is 270 gsm so I guess Heavy Weight will pass correctly. Calibrate and profile on Litho realistic, select Heavy Weight in the driver, use the applications CM (Photoshop or Qimage) + the new profile and I wonder what will not fit the Epson 4000 gamut. Also check what you prefer in red green and blue mixes between the Epson 4000 and the Z3100 samples then. There are things that have to be improved but I'm not shy of finding other routes till that is solved. That has been the case with Epsons 3000, 9000, 10000 that I owned before.

Btw, the gamut cuts are a nice representation. A bit more ink and the HP Z3100 stacking order could get different.

[a href=\"index.php?act=findpost&pid=106946\"][{POST_SNAPBACK}][/a]
The above is correct. The earliest versions of the Z 12 ink (long before release) had higher inking loads but the tonal scale was handicapped, and contouring a problem on matte and heavy relatively uncoated papers. So it is possible but the compromise will quickly go past the advantages ....
Since what is in the domain of driver users requirements, if most things work well then that is where further dev can be left to RIP developers. With ImagePRint it will be a renaissance for this Z3100 I'm sure.
The problem with higher ink-loads will result in cockle of the media. How much and how far is something that I'm confident is under investigation as I write.
As far as saturation, rather dark saturation for both Canon and HP (I'm sounding like a broken record) is an affect of pigment loads which is a whole 'nother topic.
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Panascape
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« Reply #16 on: March 16, 2007, 09:18:11 AM »
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Neil

Your comments have also been valuable as they show diverse testing methods and requirements from the device. I know I have posted mainly about reds, but the blues and greens do concern me somewhat for the same reasons the reds do albeit to a lesser extent.

Your comments about paper types is extremely valid, this is why I am working closely with HP to produce comparisons on numerous papers with the aim of being able to good a good cross section of data for comparison and analysis.

I have always been prepared to admit that there are areas in the gamut where the HP performs superbly on most Medias and have never been afraid to point this out but I have also been careful never to bash the HP and to continue to point out that Hp is working on the issues and report improvements where they happen.

I do not remember jumping on HP for their newsletter, infact I have said very little about it.
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neil snape
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« Reply #17 on: March 16, 2007, 09:35:54 AM »
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We are doing the testing comparing the machines under very controlled conditions.

The issues we are seeing is a result of what is coming out of the machine prior to profiling and this cannot be tweaked in the driver or afterwards as you cannot get  machine to lay down more ink thank its paper profile will allow unless you use a different profile which can cause over inking. Also laying down more ink is not always a solution as the z3100 uses complex colour mixing.

HP is busy looking at the colour mixing and a way to improve the results.

"The approach you have is: HP provides me a printer, paper, ink, a profiling solution or profiles, when I use that all I can't get the dark reds/colors of my Epson 4000"

This is certainly not our approach, the tests are being done with three different profiling solutions and hardware so our approach is far more complex and scientific that it may seem and this has meant that we managed to rule the profiling process out as a contributing factor as all three processes generate the same scenario.

Additionally there is more than one of us doing the controlled testing and there is at least one other model of Epson involved.
[a href=\"index.php?act=findpost&pid=106955\"][{POST_SNAPBACK}][/a]


Yes they are doing what they can within the scope of the fixed elements in building media set ups. Why is it so difficult to understand that for each inkset there are advantages , disadvantages, better worse, whatever strong point a weak point?
Since almost everyone knows, the Epson pigment inksets both K3 and UC have better dark saturation. That's on all media. The reds in the darks are the best you'll get from Epson over Canon and HP. Canon has a red extension though that neither HP , nor Epson will do in saturated mid tone reds. It is very region specific as Canon use a RGB additional primary inkset whereas HP is OGV. HP have wonderful greens and blues and pretty much everything you'd want in the above shadow colours well into the bright colours. So many of the colours are closer to anything you'll shoot in dSLR cameras with the Z that you will never have with any Epson today.
All this is still ignoring the fact that there is a compromise of the gamut boundaries of the primaries for better lightfastness.
Since you use the term ink mixing , perhaps try mixing Epson Magenta + yellow into the Z M+Y ink tanks and  see what the mix will do. Such a hybrid should be easy to make. Separations on the other hand would be very difficult.
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neil snape
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« Reply #18 on: March 16, 2007, 09:54:31 AM »
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Neil

I do not remember jumping on HP for their newsletter, infact I have said very little about it.
[a href=\"index.php?act=findpost&pid=106989\"][{POST_SNAPBACK}][/a]

I didn't name names. I cut out some lines here and there.
It is good to hear that you are aware that HP is very much intent on helping solve making better media set ups not only for you, yet through your insistance, for all users.
Yet through the postings and associations I have received numerous PM's with doubts about the Z printers on the whole. Denouncing the Z as being an inferior product, broken , incapable,  is quite the opposite of the truth if all is based on reds on certain media, and or types. If there is a truth that all this brings to light , it is the fact that all  3 makers of printers have their plus and minuses. The Z was made with certain IQ attributes that were deliberated over painfully, I'll add to favour lightfastness. No one is defending the bottom of the Lab plots of HP , nor Canon over Epson's very well done colour space. In fact there are benefits for all three in certain regions.
These are all areas of study that all three are very aware of. Possibly in the future Epson will push the envelope for brighter colours by adding more primaries (even though they deny the notions ) and HP and Canon will find new ways to have higher pigment loads. Who knows?
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Ernst Dinkla
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« Reply #19 on: March 16, 2007, 10:55:12 AM »
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The above is correct. The earliest versions of the Z 12 ink (long before release) had higher inking loads but the tonal scale was handicapped, and contouring a problem on matte and heavy relatively uncoated papers. So it is possible but the compromise will quickly go past the advantages ....
Since what is in the domain of driver users requirements, if most things work well then that is where further dev can be left to RIP developers. With ImagePRint it will be a renaissance for this Z3100 I'm sure.
The problem with higher ink-loads will result in cockle of the media. How much and how far is something that I'm confident is under investigation as I write.
As far as saturation, rather dark saturation for both Canon and HP (I'm sounding like a broken record) is an affect of pigment loads which is a whole 'nother topic.
[{POST_SNAPBACK}][/a]

Neil,

There are some reasons why I do not think that the ink load will be too high for the Hahnemühle PhotoRag 310 gsm, not in the bleeding aspect nor in cockling of the paper. There's a heavy coating (3 layers on that paper and I have checked it with my QTR linearisation targets for bleeding, there's no problem). The paper is heavy enough, no cockling on the printer or afterwards. That was practice. BTW the Artist canvas media profile must have even more ink.

The theory: the heaviest ink loads in CMYK printing are at the dark colors where saturation or composite grey require much ink and more black generation can not be used when black dot size gets too visible. In CcMmYK it happens at the point where black isn't taking over yet and the LM and LC + Y has to make the composite grey, 49>50 % on the old Epson model paper settings. The RIPs often set the LM>M partition point at 33% and have black generation start at 50%, that reduces drying time, dotgain, etc but is a compromise in smoothness. The last issues are already solved by the K3 grey inks and on the Z3100 K4 grey inks for matte papers. Composite grey mixes are taken out by the grey inks + an extended black generation as the lighter grey ink droplets are not that visible. That the pigment load in the lighter grey inks isn't as nice (still better than the equal complete composite mix though) can be compensated partly by using darker grey ink mixes than equivalent CMY mixes would deliver, there has to be made a compromise between dot visibility (droplet size, dot contrast to the printed background) and pigment load but that's easier to achieve in a set of grey inks than with cmY composite grey mixes. A single or dual minimum droplet size helps here too. So far this isn't new though the single size droplets of the new thermoheads may adapt better to this than the variable size droplet systems . The next step with N-color should take out part of the saturated composite red, blue, green, violet, orange mixes by substitutions in the CMYK mixing with the extra hue pigments. In RIPs for N-color that happens at hue angles or at hue angles + saturation points. The last will only use the extra hue inks where CMY mixes start to fail in saturation and let the CMY mixes cover the easy part. It could mean extra saturation in heavy pigment loaded inks or compensation for lower pigment loaded inks (the old Roland HiFi models with pigment inks). Substitution at hue angles would reduce CMYmixes all over and by that ink load but must be more complex to manage. In total N-color is a lot more complex as you do not want to get a gamut shape that has bubbles or dents at several places. In the end it is the pigment load of the ink and the transparency<>chroma relation of the pigment particles (the chroma/density shift in linearisation targets) that make the gamut size, that works the same in CMY inksets and in N-color inksets, though N-color mixes can handle less transparent inks better (there's less mixed). In the Z3100 it wouldn't surprise me if the heaviest inkload om matte papers is in the 100% matte black patch. A lot can be compensated below that point. It wouldn't surprise if there's a far better way of mixing N-color inks than what I described above, theory advances too.

Ernst Dinkla

try: [a href=\"http://groups.yahoo.com/group/Wide_Inkjet_Printers/]http://groups.yahoo.com/group/Wide_Inkjet_Printers/[/url]
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