It seems strange that the vacuum setting comes after the paper feed adjustment.
Hi Robert, that is a very good question. I thought about it myself too until I worked with the SU-21 spectro on a iPF6460. I noticed that when creating unique calibration data for new media, it runs the paper feed adjustment again. So I figured, one should skip this step during the new media build. The MCT will warn you of problems but just skip it first, determine your vacuum strength and head height and create the .am1 file. After it is created, then click on edit, and run the paper feed adjustment. That is the way it should be done. or else the adjustment may be wildly inaccurate, because the MCT may pick different head height and vacuum strength settings. It is easy to check if you have a pocket microscope. Not many know about doing it this way!
Don't forget to export your .am1 files when you are done creating the new adjustment data, and back them up.
I've just done a print using a roll of Canson Platine 310gsm and I'm getting ink marks at the sides of the paper.
The paper path of the iPF64XX may be to blame. Testing extensively with my dealer's demo printer, I always get head strikes at the beginning of the roll, because the natural curl of the paper raises the front end just slightly too high as it passes over the platen. After the first bit of the roll has gone through, it prints just fine. Sometimes the lowest head height is ok, but I find it safer to keep it at 'low'. I still had head strikes, again only for the intial three inches or so, after which it was fine. Vacuum strength should be strong or strongest (I prefer the latter). The vacuum is able to hold down the paper more in the center so that's why the marks are only on the sides.
A simplified drawing:
Do beware the pizza wheels at the ejection point of the paper path. If the paper is too curly, it will impact the pizza wheels. While they are there to guide the paper, it marks glossy media like Patine with tiny perforated markings. Watch out for that. Again it only happens for the initial portion of paper. Guiding it with your fingers as it passes out is how I worked around the problem.
If that's the case, could you not use, for example, the calibration on the Platine just as well as the calibration from one of the Genuine Canon papers?
No, as it is not a genuine canon paper the printer will not use it this way, even when you have the spectral data. Probably a way to push the sales of Canon papers.
Tomorrow, when I get back to the studio, I will download again the settings and compare.
Well, at least you got rid of the marks on the edge.
Scott Martin has advocated calibrating on your favorite (high quality) paper that you always have lying around, not genuine Canon media, especially if that is hard to get where you are. (Same problem here in Singapore Geraldo!) The point is that when you next need to recalibrate, you will have that paper in stock and you don't have to re-do all your profiles, which you will need if you calibrated to a different paper. He explained to me that the calibration process is in fact a simple linearizing function, no matching to any reference data. The printer measures paper white and dmax, and adjusts all the patches in between to fall in regular steps. He claimed to have spoken with Canon engineers who first explained it to him said it is ok to use third party high quality papers for calibration.
As Geraldo pointed out, these new iPFX4XX have media files associated with "common calibration" or "unique calibration" properties. Common calibration applies calibration information across all media types after calibration is performed once. It is highly recommended that you do this - no in fact it must be the first thing you do when setting up the printer. I'm less sure if unique calibration is useful. Imagine a print head swap down the road - instead of performing one common calibration and be done, you will have that to do that plus all your third party papers unique calibrations. A lot of additional paper and some ink to be wasted.
I have performed common calibration on third party papers with no problems. It is best to use very high quality media, and keep the same roll around for re-calibrations in the future, in case the paper formula is changed down the road and a new roll invalidates all your profiles.
My own experiments also indicate that common calibration on glossy media yields better gamut performance than matte media. Profiles for matte media are about 4 - 6% larger, comparing to calibration made on matte paper. The improvement on glossy is only 1-2% larger, within ColorThink Pro's margin of error in gamut calculations so no conclusions there.
Coming back to if calibrations should be done on genuine paper - I'm not 100% sure if it will be better or you will see no difference, or perhaps it might be worse. Worse perhaps because calibrating to your favorite glossy paper might set up the printer more optimally (my guess is that's most likely the case). But perhaps looking at the way the unique calibration spectral data is built using the SU-21 spectro and the iPF64XX printer might reveal something - the MCT advises to perform common calibration on genuine paper before printing out the color target - implying that the printout of the color target is affected by the calibration - hmmm.
Geraldo, my own tests on unique calibration vs common calibration shows minimal differences just as you reported in a different thread. Again matte media shows more significant differences than glossy media, though only slightly. Certain ranges of color are affected more than others, but there is also a tiny improvement in deepest black separation, which is always nice. On glossy it almost seems not worth the effort, but I do it anyway. Now that I have an iSis, it is much easier to re-profile whenever I need to. Plus I have also noticed that sometimes re-calibrations shift the printer behavior enough to warrant re-profiling. Still, perhaps it is always better to have unique calibration for the paper you are using, to account for any special (subtle) differences.