Ad
Ad
Ad
Pages: [1]   Bottom of Page
Print
Author Topic: IPF8400 / 8300 calibration  (Read 1075 times)
Geraldo Garcia
Full Member
***
Offline Offline

Posts: 167



WWW
« on: March 02, 2014, 03:57:49 PM »
ReplyReply

Two days ago our IPF8400 was delivered and so far I am quite impressed with it.
Being a long time HP Z3200 user I am sill getting used to the new printer and developing a workflow and I am having a hard time with one detail:

The printer does not have an internal spectrophotometer as the Z3200, so I will make my custom profiles with my external spectrophotometer. But it has an internal "multi-sensor" (densitometer) to perform calibration (linearization). On the Z3200 we should perform the calibration for each paper before profiling it, but I am uncertain about the IPF8400. Some (non reliable) sources mention that the calibration should only be performed occasionally and always with the paper supplied with the printer (Canon coated heavyweight) as it is a "printer level calibration" and not a "paper level calibration" as on the Z3200. Although it can be truth I don´t think it makes much sense.

Can you, more experienced IPF users, help me with that? Thanks in advance!
  
« Last Edit: March 02, 2014, 04:53:05 PM by Geraldo Garcia » Logged
Czornyj
Sr. Member
****
Offline Offline

Posts: 1371



WWW
« Reply #1 on: March 02, 2014, 04:18:36 PM »
ReplyReply

In case of Canon you only make only one linearisation on any supported Canon paper, and it's automatically applied to all other linearisations for all other paper kinds. In fact you can't really make more than one linearisation, as each linearisation overwrites the former one.

It may not be convincing at first, but it works Wink And it's also much more convenient than relinearising all existing paper types (like one HP or Epson) every time you need it.
« Last Edit: March 02, 2014, 04:22:43 PM by Czornyj » Logged

Geraldo Garcia
Full Member
***
Offline Offline

Posts: 167



WWW
« Reply #2 on: March 02, 2014, 11:36:26 PM »
ReplyReply

Thanks Marcin,

I will swallow that eventually, but I must confess that I still have it stuck in my throat. Cheesy
It is just weird...
There is an option on the printer´s status monitor software to display the calibration log that lists all the papers installed on the printer and their calibration status. That makes me believe every paper should be calibrated, but the manual does not say that explicitly.
I will keep hammering my head on that and will make some tests.

Best regards.   
Logged
Geraldo Garcia
Full Member
***
Offline Offline

Posts: 167



WWW
« Reply #3 on: March 03, 2014, 07:08:49 PM »
ReplyReply

Some news:

Digging the manual and the software I discovered that both things are possible, apparently:

You can (should) perform a general calibration with the supplied paper (or any supported Canon paper) and that calibration will be extrapolated to any other paper (Canon, third party or custom). That is exactly what Marcin and some other sources said, but there is more! You can perform paper specific calibrations for third party and custom papers and this calibration data will only be used on that specific paper. Apparently there are some things that must be done during the custom paper creation to allow it to be calibrated individually (some reference data must be provided), otherwise it will only make use of the general calibration.

Quote
From IPF8400 user guide, pages 835 & 836:
"Common calibration is a feature that allows you to use multiple media types easily in a short time because it is not
necessary to execute color calibration on each media type.
If color calibration is executed on paper categorized as Common calibration, dedicated calibration adjustment values
are set on the media type that Common calibration was executed on.
Furthermore, calibration adjustment values are set on all print qualities for all media types where color calibration
has not been executed.

If color calibration is executed on paper categorized as Unique calibration, calibration adjustment values are set
only for the media type that the color calibration was executed on.
Even if paper categorized as Unique calibration is used, if the media type has yet to execute color calibration even once
and does not have any dedicated calibration adjustment values, the calibration adjustment values are overwritten when
Common calibration is executed."

I tested it with some third party (Canson) papers that have the calibration data on the media configuration file and it worked! I was able to make a paper specific calibration that does not affect the other papers.
Will keep digging.

Best regards.
Logged
samueljohnchia
Sr. Member
****
Offline Offline

Posts: 256


« Reply #4 on: April 18, 2014, 11:05:49 PM »
ReplyReply

As most users of the iPFx100 and later printer models know, knowing how to utilize the in-built calibration function of the printer is vital to the optimal use of these machines. The way it works is has changed slightly in the iPFx400 series of printers, as Geraldo Garcia has pointed out in this thread. My own independent investigations led me to a similar discovery, and after reading this thread and exploring further, I would like to share my findings.

Prior to the iPF x400 printers, there can only be one active universal calibration, using one of the compatible media types. Recalibrating using the same paper, or a different media setting or a different paper will overwrite the previous calibration and the new calibration will be applied to all the installed media types.

For the iPF x400 printers, it is possible to have media specific calibration. Essentially, there are three general scenarios, and a special forth one which I will get to later:

1. First calibration: Performed on one of the "Common Calibration" media types, it is applied to all the media types installed in the printer, including the "Unique Calibration" media types.
2. Subsequent calibration on a different "Common Calibration" media type. It is applied to all the media types including the "Unique Calibration" media types, but not to any with calibration already performed on them.
3. Calibration on "Unique Calibration" media types. This is media specific and is not applied to any other media types. Subsequent calibration on the "Common Calibration" media types will not affect it.

The "Common Calibration" and "Unique Calibration" media types are listed in page 752-753 of the iPF Users Guide:


 
If one checks the Calibration Log in the printer menu, it will only show the latest calibration performed. For media settings that have its own active calibration data stored, the log will update to reflect this only when paper is loaded and that media type selected for the paper. To make it easier to keep track of all active calibrations, one can use the ImagePROGRAF Color Calibration Management Console. It lists the calibration status of all media types and it is easy to see when there is more than one calibration active.



This is the forth scenario:
Since the iPF x300 printers, the Media Configuration Tool has allowed users to create custom media types. It is not possible to perform calibration on custom media that end users can create with the MCT. Page 747 of the Users Guide explains why:

Quote
When using paper other than genuine Canon paper and feed certified paper
To execute color calibration on paper other than genuine Canon paper and feed certified paper, a Custom Media Information File that contains a dedicated Calibration Target is required.
As long as you have a Custom Media Information File that contains a dedicated Calibration Target for paper other than genuine Canon paper and feed certified paper that was created on a printer (12-color model) with a Spectrophotometer Unit mounted, it can be registered in the printer by using the included MCT and you can execute color calibration even on paper other than genuine Canon paper and feed certified paper.

So there is indeed some "Calibration Target" data (not reference data) that unlocks/allows calibration on custom media installed on printers without the spectro!

At this point, it means only the iPF6450 with the spectro accessory talking to its MCT can build this file. Once you have created the .am1 file, you can import it to any x400 printer and make media specific calibrations with just the built-in calibration function, just like Geraldo Garcia did with one of Canson's custom media type.

This part puzzles me. After conversing with Scott Martin over email, my understanding of the built-in calibration routine is essentially linearizing the printer for that paper. It is hard to imagine that the target is built into each .am1 file instead of stored on the printer. A check of my custom made .am1 file without the data is 945kb, and Canson's with the "Calibration Target" data is the same size. It is unknown as yet why Canon chooses to lock out the ability to calibrate on custom media for the other iPF x400 printers, and what importance the spectro accessory has to play in creating the target data.

I want the ability to calibrate custom media types. I think it is useful for all of us who don't use a RIP. Media specific calibration is the closest to RIP linearization - I like the well behaved linear state of the printer before profiling. Native printer performance on matte media is not as linear when doing a general calibration on glossy media. I should say though, that the differences are usually minor and only the fussy demanding sort of people will want to do this, and the profiling step afterwards usually levels out most issues.

If you own a iPF6450+spectro but you want to calibrate your custom media types, hopefully you have a nearby friend or a dealer that does and lets you borrow theirs. Page 749 of the Users Guide has the procedure for setting up custom media with the Calibration Target:

Quote
You can also reduce the variations in printed color tones when using paper other than genuine Canon paper and feed certified paper by creating a Calibration Target by using a printer with a Spectrophotometer Unit (optional) mounted and the included Media Configuration Tool (MCT).
You can also execute color calibration even if you are using paper other than genuine Canon paper and feed certified paper by registering a Custom Media Information File that contains this Calibration Target using the included MCT on a printer (12-color model) that supports calibration link without a Spectrophotometer Unit mounted.

Furthermore, it is also possible to execute color calibration on paper other than genuine Canon paper and feed certified paper even on remote printers (12-color models) that support calibration link by sending the Custom Media Information File that contains the Calibration Target by e-mail.
This allows you to operate efficiently and at reduced cost because you can perform calibration operations on the paper you are using that unify color tones across workplaces.
The following procedure using MCT is needed in order to perform color calibration on paper other than genuine Canon paper and feed certified paper.
1. Register the media information using Add Custom Paper.
2. Add the Calibration Target information in Create Calibration Target to the created custom paper.
3. Save as a Custom Media Information File that contains the Calibration Target.
4. Add the Custom Media Information File to a printer (12-color model) that supports calibration link without a Spectrophotometer Unit mounted.
5. Execute color calibration using the printer or the CCMC color management utility.

If one has a number of media specific calibrations, take note that in the event you are performing routine re-calibration to account for printer drift/print head change, do note that you would have to re-calibrate for all those media types again. For most users, the general calibration will suffice and makes life a bit easier. That itself provides the greatest output quality difference, and makes it easier to perform one-time recalibration.
« Last Edit: April 18, 2014, 11:26:00 PM by samueljohnchia » Logged
Geraldo Garcia
Full Member
***
Offline Offline

Posts: 167



WWW
« Reply #5 on: April 19, 2014, 01:12:06 AM »
ReplyReply

(...)This part puzzles me. After conversing with Scott Martin over email, my understanding of the built-in calibration routine is essentially linearizing the printer for that paper. It is hard to imagine that the target is built into each .am1 file instead of stored on the printer. A check of my custom made .am1 file without the data is 945kb, and Canson's with the "Calibration Target" data is the same size. It is unknown as yet why Canon chooses to lock out the ability to calibrate on custom media for the other iPF x400 printers, and what importance the spectro accessory has to play in creating the target data.

Me too! I can only imagine that the printer with the spectro would be able to make some additional initial readings that are needed for the calibration to work. When we think that the IPF printers have a densitometer and not a spectrophotometer that "kind of" makes sense, as the densitometer is "colorblind" and can only measure density (as the name says). Some info about the paper´s "tint" probably is needed for a unique calibration. But that is a guess.

At this moment Canson provides .am1 files allowing unique calibration. I already spoke to some friends on Hahnemühle and they said they are working to provide the .am1 files.

Thanks for the additional info, Samuel!  
« Last Edit: April 19, 2014, 01:08:57 PM by Geraldo Garcia » Logged
samueljohnchia
Sr. Member
****
Offline Offline

Posts: 256


« Reply #6 on: April 19, 2014, 01:51:47 AM »
ReplyReply

Me too! I can only imagine that the printer with the spectro would be able to make some additional initial readings that are needed for the calibration to work. When we think that the IPF printers have a densitometer and not a spectrophotometer that "kind of" makes sense, as the densitometer is "colorblind" and can only measure density (as the name says). Some info about the paper´s "tint" probably are needed for a unique calibration. But that is a guess.

Maybe. I don't know for sure. A spectro is not really needed for linearity measurements. However, I have observed the calibration routine of my iPF8400 carefully, and it definitely measures paper white as well. The am1 files are the same size, so I don't know how they are storing this additional target. Maybe it's just a tag in the file that "unlocks" the calibration function. I should be able to get my hands on a 6450 with spectro and make some of my own am1 files and experiment.

At this moment Canson provides .am1 files allowing unique calibration. I already spoke to some friends on Hahnemühle and they said they are working to provide the .am1 files.

Excellent! Hopefully they test the media types carefully before building the am1 files. Canson chose "Fine Art Textured" which isn't as good as "Fine Art Heavyweight Photo" or "Fine Art Photo" which are exactly the same in inking.

Quote
Thanks for the additional info, Samuel! 

You're welcome. I'm surprised that others have not picked up on this yet. A lot of good information used to be shared, especially on the Canon iPF wiki. These new printers bring additional things to look out for and they are not documented. The media types have changed as usual and those doing their own custom profiling may not be aware of these changes. I would say the paper companies should be responsible for this testing but I'm skeptical about trusting their results.
Logged
Czornyj
Sr. Member
****
Offline Offline

Posts: 1371



WWW
« Reply #7 on: April 19, 2014, 03:11:43 AM »
ReplyReply

Maybe. I don't know for sure. A spectro is not really needed for linearity measurements. However, I have observed the calibration routine of my iPF8400 carefully, and it definitely measures paper white as well. The am1 files are the same size, so I don't know how they are storing this additional target. Maybe it's just a tag in the file that "unlocks" the calibration function. I should be able to get my hands on a 6450 with spectro and make some of my own am1 files and experiment.

A spectrophotometer is necessary for creating a target for spectrodensitometer - this is quite obvious. On the other hand I agree it's a shame that you need iPF6450SP to create calibration target, the spectrophotometer unit is basically an i1Pro2, so it wouldn't be a problem to use external sensor instead of SU (which can only be mounted in iPF6450 BTW).
« Last Edit: April 19, 2014, 03:14:34 AM by Czornyj » Logged

samueljohnchia
Sr. Member
****
Offline Offline

Posts: 256


« Reply #8 on: April 19, 2014, 03:37:30 AM »
ReplyReply

A spectrophotometer is necessary for creating a target for spectrodensitometer - this is quite obvious.

Sorry this is new to me. What kind of target will a spectrophotometer help create? Reference values?
Logged
Czornyj
Sr. Member
****
Offline Offline

Posts: 1371



WWW
« Reply #9 on: April 19, 2014, 04:16:09 AM »
ReplyReply

Sorry this is new to me. What kind of target will a spectrophotometer help create? Reference values?

Like Geraldo already mentioned, a spectrodensitometer is "colour blind" - it can only measure density of ink, but it doesn't report what colour it really is. Therefore an initial linearisation must be carried out by a spectrophotometer, which "sees colours". After initial linearisation you can measure reference densitometric values and create a target for further relinearisations with spectrodensitometer.
« Last Edit: April 19, 2014, 04:18:57 AM by Czornyj » Logged

Scott Martin
Sr. Member
****
Offline Offline

Posts: 1311


WWW
« Reply #10 on: April 19, 2014, 10:55:14 PM »
ReplyReply

Like Geraldo already mentioned, a spectrodensitometer is "colour blind" - it can only measure density of ink, but it doesn't report what colour it really is. Therefore an initial linearisation must be carried out by a spectrophotometer, which "sees colours". After initial linearisation you can measure reference densitometric values and create a target for further relinearisations with spectrodensitometer.

I like you're line of thought here. It seems probable that Canon has established a process by which they do their initial characterization using a spectro that is later re-linearized with the densitometer. Perhaps they could come up with a new procedure that would allow an end user to do this on custom media without the spectro but they haven't so until then it's only available with the 6350+spectro. Fair enough.
Logged

Pages: [1]   Top of Page
Print
Jump to:  

Ad
Ad
Ad