i1 Photo Pro -- UV cut or Not?

[traveller]

I am about to purchase X-Rite i1 Photo Pro -- on what basis does one decide whether to purchase the UV cut version or the standard one?

Lloyd ....

[scott morrish]

If your choice of paper includes stock that uses optical brighteners... then you might need the UV cut version... i am not 100% sure.
No doubt there are other factors, and others will be able to shed more light on this than i can, but i think the papers you use are the key factors.

My interests are specifically in working with papers that do not have optical brighteners in them, and by chance i also want to be able to proof for CMYK press conditions. In these circumstances... the 'non UV' Eye1 is appropriate.

Scott

[howardm]

I know there was a long-ish thread just recently on this topic.

The search function returned this (in addition to other prior threads)

http://www.luminous-landscape.com/forum/index.php?topic=60534.0

[Luca Ragogna]

... i also want to be able to proof for CMYK press conditions. In these circumstances... the 'non UV' Eye1 is appropriate.

Heidelberg supplied a UV cut i1 with their proofing solution when our company bought a printing press because a lot of the proofing papers have OBAs so I would lean towards the UV cut version for Press proofing. Also, I'd probably get the UV cut version just so that I'd have the option of profiling papers with OBAs.

[Ernst Dinkla]

Outdoors display where you can be sure that UV will be part of the lighting a spectrometer without UV-cut filter should be the right choice for both OBA and Non-OBA media. The profile creation software should be compatible with that UV enabled spectrometer, not all are.

Indoor display where you can be sure that UV will not be part of the lighting a spectrometer with an UV-cut filter should be the right choice for both OBA and Non-OBA media. The spectrometer/driver/software will fill in the spectral measurements below 420 NM (or even higher) wavelength based on an extrapolation of the numbers above 420 NM. That is not always working nicely. Where UV filtered glass is used in windows and/or in the print frame you get to that condition of no UV light available. The use of OBA media is then also not sensible as there is no UV available to trigger fluorescence in the paper white.

Any condition in between, indoors, can usually be done with an UV-cut spectrometer though it is wise to select media with low OBA content, just enough to neutralise the white and it is wise to avoid too bright "blue" media choices at all. Not just because you can not measure them properly but they tend to have more "M", and they might shift their paper white color faster in time due to OBA destruction (both light and gas fading). For the best selection of media see my signature and for ink + paper white shift tests see the link to Aardenburg there.

"M" here represents color inconstancy of one color sample in changing light spectra, more often incorrectly called metamerism.


met vriendelijke groeten, Ernst
Shareware too:
330+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm

[MonsterBaby]

the FOGRA standards are all measured without UV filter. thats a fact.

some make a big thing out of it of not beeing precise and fulfillingt contract proof ISO norms..

in fact tho if the proof paper doesnt have much OBAs ( wich they usually dont of course) the values are gonna be pretty simular

[Ernst Dinkla]

the FOGRA standards are all measured without UV filter. thats a fact.

some make a big thing out of it of not beeing precise and fulfillingt contract proof ISO norms..

in fact tho if the proof paper doesnt have much OBAs ( wich they usually dont of course) the values are gonna be pretty simular

There are several proof paper measurements in my SpectrumViz  collection and I am curious whether they are identical per Fogra standard. What I see is that there are still versions with OBA content that give a more than 100% "reflection" at 440 NM and plots that are identical to ordinary RC papers used for other purposes. Papergraphics (UK and NL distribution) has two qualities loaded with OBA that resemble the cheapest RC qualities of Red River. I wonder if they ever measured that paper with a Non-UV cut spectrometer. Enough offset papers with OBA content of course but not to that degree. Proof papers with hardly any OBA can be counted on one hand while there is a wide catalog of offset papers in that category.


met vriendelijke groeten, Ernst
Shareware too:
330+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm

[Ethan_Hansen]

I am about to purchase X-Rite i1 Photo Pro -- on what basis does one decide whether to purchase the UV cut version or the standard one?

Quick answer: If you plan to use printer profiling packages such as Argyll (free) or basICColor Print ($1500) that offers software correction for optical brighteners, go with the standard i1 Pro. If you will be using either the bundled X-Rite software or i1Profiler, hold your nose and get the UV-Cut version.

Not so quick explanation: The standard model offers better measurement accuracy in darker colors and at the blue end of the spectrum. This is compounded by the UV-Cut model inventing data for readings of 400nm and below. The charts below compare measurements from a standard i1 Pro to a UV-Cut model on a paper with moderate optical brightener levels. The first three bars at the left of each chart are 380, 390, and 400 nm remission values. The UV-Cut model has a filter over the light source that effectively cuts output at wavelengths shorter than 400 nm. Why, then, does the UV-Cut instrument report higher output at short wavelengths? X-Rite's SDK extrapolates readings for short wavelengths, and given that these readings are almost pure noise, nonsense results. The UV filter is doing its job as evidenced by the reduction of the brightener-induced peak in the 430-450 nm range.

My suspicion is that this explains in part the overall superiority of profiles made with standard (non-cut) instruments on papers with either low levels of OBA or no brighteners at all. Unfortunately, X-Rite's new i1Prism profiling engine lacks the OBA compensation algorithms found in the old ProfileMaker code. These algorithms performed well on most substrates. It appears that X-Rite was seduced by the power of the iSis to thoroughly decouple UV from non-UV data. The iSis brightener compensation routines in i1Profiler do indeed work well (assuming you are only profiling a single printer at a time and can work around the rest of the disasters that are the OBC workflow). Leaving in the software OBA compensation from ProfileMaker would have worked 90% as well for iSis users and given i1-Pro owners a better choice than the "see no evil UV" option of using a UV-Cut instrument.

[Photopro888]

I have read all recent post about the two versions, but I’m still not sure which one to get. I want to use the i1Profiler software that comes with the “X-Rite i1Photo Pro” If most of my printing (75%) will be on paper and canvas with anywhere from a little to a lot of OBA, should I still buy w/out the UV and if so, do I need to anything special when making the profiles.

Or am I better off with the UVCUT version since most of my paper and canvas will have some OBA in it.

Thanks,
Darren

[Scott Martin]

I'll keep it short and sweet and suggest you get the UV Cut version. I think you'll find it and i1Profiler to be perfect for 100% of your profiling needs. :-]

[digitaldog]

I'll keep it short and sweet and suggest you get the UV Cut version. I think you'll find it and i1Profiler to be perfect for 100% of your profiling needs. :-]

I agree. Short of a unit that can read both, or two separate units, this is the best solution for unknown profiling conditions.

[Scott Martin]

Short of a unit that can read both...

Yep, that's what I'm thinking too!

[MHMG]

If you only can purchase one unit, it is indeed a tough call. Personally, I'd opt for the UV-included version and constrain my media purchases to media that have little or no OBA. Why? Because media white point stability will be better over time and also not differ so much in color appearance under varying light sources.  Also, profiling will not be messed up trying to deal with the vagaries of UV-induced fluorescence caused by the illuminant if the media doesn't fluoresce very much.
How do you tell high OBA content media? A simple black light will sort high OBA content papers from low or no OBA content papers. And the non-UV cut Eye One Pro will also return b* values that go increasingly negative with increasing OBA content. So, if you use the Eye One non-Uv cut instrument and measure b* values on the media that are not less than zero, you will have identified papers with little or no OBA content. You can't do this test with a UV cut instrument.

You can also identify media with little or no OBA content by using some website resources:

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
http://www.aardenburg-imaging.com/cgi-bin/mrk/_4899c2hvd19kb2NfbGlzdC80

cheers,
Mark
http://www.aardenburg-imaging.com

[Photopro888]

Thanks everyone for the replies - looks like the UV Cut version is the one!

Darren

[MonsterBaby]

found a very interesting article on this..

http://www.google.de/url?sa=t&rct=j&q=icc%20white%20backing%20black&source=web&cd=1&ved=0CCoQFjAA&url=http%3A%2F%2Fwww.color.org%2FICC_white_paper3measurement.pdf&ei=1fdTT5HHCcyYOp7v7SI&usg=AFQjCNHJXh8qg8voaiHrgTB_31Nu2YyJqg&cad=rja

[SergeyT]

Just curious, would it be possible to take advantage of the i1Pro UV-Cut built into HP z3200 with i1Profiler software?
It is  possible to import (CGATS format) and print custom color charts on z3200.
It also possible to automatically measure the printed charts and export the measurement data into CGATS format files.

So the questions are:
1. Is it possible to export the charts generated by i1Profiler into CGATS format files?
2. Is it possible to import the measurements data in CGATS ( done on z3200) back into i1Profiler and generate a profile?

Thank you,
SergeyT.

[MonsterBaby]

yes. all possible.

BUT.. no one actually wants to use the swatches the Z prints as they are tremendously BIG!! i dont know why hp did it.. if they couldnt be more precise?? i doubt it with a precision of a printhead!.. but its such a waste of paper and ink that i hate using it!

with the advanced profiling solution though you can use your own and any testchart RGB and CMYK and print it. measure it and export the cgats data instead of building a profile

"Is it possible to export the charts generated by i1Profiler " not sure about that.. you can do it with colorport charts and profilemaker so why not with i1profiler

[Ernst Dinkla]

BUT.. no one actually wants to use the swatches the Z prints as they are tremendously BIG!! i dont know why hp did it.. if they couldnt be more precise?? i doubt it with a precision of a printhead!.. but its such a waste of paper and ink that i hate using it!

with the advanced profiling solution though you can use your own and any testchart RGB and CMYK and print it. measure it and export the cgats data instead of building a profile

"Is it possible to export the charts generated by i1Profiler " not sure about that.. you can do it with colorport charts and profilemaker so why not with i1profiler

It most likely is not the precision of the spectrometer positioning but the wider vertical distance between the spectrometer and the patches that made them decide to make larger patches. I can not complain about the economy of the targets, with a good profile once made over the full width of a roll you can calibrate with much smaller waste paper pieces later on.

With the optional APS there is a lot possible with other profile creators and for other printers. Even with odd ones like QTR profile creator that I tried. The HP Color Center profile creator software on the Z3200 has also more features for that than CC has on the Z3100. At least on my Z3200-PS. Check the possibilities of CC. What the im- and export of i1Publisher allows I do not know but I agree that it should be possible on a program like that. The UV-cut spectrometer of the Z's should at least fit the non-iSis settings of i1Publisher. However the Z's spectrometer may not be a direct copy of the i1, white LED instead of tungsten has been mentioned and I have seen more suggestions.


met vriendelijke groeten, Ernst
Shareware too:
330+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm

[MonsterBaby]

@ernst  if you try building 7color profiles for a RIP you damn the Zs patches ;-)

and to mention as well, next to the UV cut measurement (which i have read somewhere doesnt actually have a UVcut filter but as ernst said because of its LEDs doesnt read UV light?).. it has black backing..

[Ernst Dinkla]

The white LED does not emit into UV so OBA is not activated.  Colorimeters often have a similar absence of UV light, more LEDs in that case and of different monochrome wavelengths but none going down into UV.

As I understand it with UV-cut filters in spectrometers based on tungsten light both light source and sensor are cut. In the iSis there are two LEDs, one white without UV, the other emitting mainly UV. The Z's may have that one white LED side of the iSis, a suggestion made by some people when the Z's were introduced.


met vriendelijke groeten, Ernst
Shareware too:
330+ paper white spectral plots:
http://www.pigment-print.com/spectralplots/spectrumviz_1.htm