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Showing posts with label i1 photo pro. Show all posts
Showing posts with label i1 photo pro. Show all posts

15 Apr 2011

i1 Profiler - Displays & Projectors






In this last blog looking at the new i1 Profiler software I’ll be covering monitor and projector profiling. The only instrument that is supported for display profiling is the i1 Pro, which is a shame since the i1 Pro spectrophotometer doesn’t measure low light values as well as a colorimeter, such as the i1 Display 2, although the i1 Pro can be more accurate at higher brightness values.

The Display Profiling workflow is pretty intuitive, even if you’ve never used a monitor profiling system before. The first option you get is to choose the White Point of your monitor, D65 (6500K) is the default. You can choose from a range of common values or measure your ambient lighting. The Luminance value defaults to 120 cd/m2. You also get to choose the Contrast Ratio, which is usually a factor of the luminance of the white point divided by the luminance level of the black point. If you are profiling multiple monitors then having the same contrast ratio can help to get a visual match. You’d have to profile each screen, see what contrast ratio each has and then set them all to the lowest value. The trouble with this approach is that most of the screens are no longer displaying at their full potential and are being dumbed down slightly.

The Profile Settings page allows you to set options such as Tonal Response Curve, Chromatic Adaptation and ICC Profile Version. Most customers won’t need to change from the defaults, apart from those using older versions of Photoshop who may find a version 2 ICC profile works better for them.

Once you click on the Measurement page you’ll see options to use Automatic Display Control (ADC) or Adjust brightness and contrast manually. Many monitors support ADC for automatic adjustment of the monitor. Both my MacBook Pro screen and my Lacie 324 have this feature, for example. Other monitors may not be able to be adjusted automatically and so you’ll have to interactively measure and adjust the brightness.

Interestingly you don’t get the option of adjusting the white point at all. i1 Profiler adjusts the video look up table of your graphics card to get the correct white point. This can be a good approach for cheaper monitors with poor controls but many monitors do have good adjustments for colour and it is disappointing not to be given the option of interactively changing and measuring the white point of the monitor. However, it did adjust the white point of my monitor using ADC but not precisely enough that it didn’t still have to make adjustments in the graphics card.

After the measurements have been done you can go on to the ICC Profile page and Create and save profile. You can then look at a graph of the gamut of your monitor and a graph of the adjustments made in the graphics card. You also get to see the range of Roman test images you get in the CMYK Printer Profiling workflow, and also have the option of loading your own. When you are viewing the test image you can click a before or after button to see the change in your monitor.

To further test your new monitor profile you can access the Display QA workflow. This takes the reference values from the classic 24 patch ColorChecker card, displays them on screen and then measures how close your monitor comes to displaying the colours accurately. Most previous monitor validation software I’ve used simply puts a series of colours through a profile, and then measures them to check the internal consistency and accuracy of the profile. The i1 Profiler approach of how well the monitor can display certain reference colours is different and I can see the benefit of it. What I would say though is that the little message you get at the bottom of the QA Report page, that the reference uses different measurements and some of the differences might be due to that, is not that reassuring. I’m assuming the reference values were done in D50 and since I profiled my screen at D65 that might be the difference X-Rite are referring to but a little more explanation or factoring in of the differences might make this feature more useful. I first profiled my display to 120 cd/m2 as usual and it failed the QA test but when I put it up to 140 cd/m2 it passed, just.


Now, I’ll be the first to admit that since I got the BasicColor Discus I have been slightly spoilt when it comes to monitor profiling. The profiles the Discus makes the best monitor profiles I’ve ever seen. That said i1 Profiler with an i1 Pro does a competent job that compares favourably with those from a ColorMunki, Spyder3 Elite or i1 Display 2. However, since i1 Profiler is X-Rite’s top of the range profiling product they could have put a few more features in to the Display Profiling workflow to reflect this. I think the lack of white point adjustment is a major omission and I also think an extended Display QA workflow that included uniformity checking would be good.

The Projector Profiling workflow is basically similar to the Display Profiling workflow, but you get no option to adjust the projector, the software simply profiles it as it is. You’ll need the Beamer attachment for your i1 Pro to profile a projector. The Projector QA workflow is also the same as Display QA. The projector profiles I got were slightly better than i1 Match.

My blog has covered all the major aspects of i1 Profiler now, but I’ll revisit it again in a few months after I’ve used the software on-site a bit more for customers. I used it yesterday for customer to profile their digital printing onto cloth and it did a very good job of profiling a difficult process and all the printer profiles I’ve made so far have been very good.

6 Apr 2011

Profile Verification & Optimization







Two of the new features of i1 Profiler are the ColorChecker Proof profile verification option and Printer Profile Optimization. We’ll start with ColorChecker Proof. The software comes with a new version of the classic 24 patch Munsell ColorChecker but this one has a twist, it has holes in it.

The idea is that you click on the ColorChecker Proof workflow in the software and then drag and drop one of the profiles you’ve made onto the ColorChecker page icon. There is a check box to show which patches are out of gamut and so not expected to be matched on the printer. You then print the ColorChecker image and then get your ColorChecker Proof target and lay it over the print out. You’ll see the printed colours through the holes in the target and be able to evaluate the accuracy of the profile.

The main problems I have with this approach is that it obviously depends a lot on the light source you are viewing the print and the target under but also assessing areas of flat colour often tells you less about the accuracy of a profile than viewing a photographic image, with a wider range of tones and real world imagery we are familiar with such as faces, that our visual system has evolved to evaluate. So whilst I think the ColorChecker Proof is a useful tool I wouldn’t use it in isolation from conventional test images.

Once you have tested a profile you may choose to access the other new feature we’re talking about today, Profile Optimization. The Profile Optimization workflow takes an existing profile and analyses which areas might need a bit of improvement and generates a new set of patches to output and measure. Patches can be generated from images or spot colour libraries as well.

The technology is based on that in the ColorMunki software. The ColorMunki software only produces an initial 50 patch set so I can see the need for generating an additional second set. However, if you start by building an i1 Profiler profile with maybe 1000 or more patches there are unlikely to be many gaps that need filling. When I’ve tested Profile Optimization with RGB printer profiles I’ve never been able to see a visible difference in the final prints between and an optimized and un-optimized profile. There may well be small measurable differences in some colours but if the differences are not visible to the naked eye then it’s debatable if the procedure is worthwhile.

With CMYK printer profile you do sometimes get a small visual improvement and a larger measured improvement in Delta E values, but the improvement isn’t large in either case. I’ll need more time to assess this feature as I begin to use the software more in the field on a wider range of printers and technologies. However, I also find it curious that you can generate up to 6000 new patches and it will always generate the number you set. It never gives any feedback saying the profile is OK and can’t be improved or that only X number of patches are needed to make some improvement. It just generates the number of patches you ask it to. The level of improvement achieved is never quantified in any way either, so I’ve yet to be convinced but time will tell.

The other related feature to the ColorChecker Proof and Profile Optimization workflows is the Printer QA workflow, but we’ll tackle that next time when we talk about CMYK printer profiling.

5 Apr 2011

Using X-Rite i1 Profiler to calibrate your screen.

Here's another video demonstration of using the new X-Rite i1 Profiler software (i1 Basic Pro, i1 Photo Pro, & i1Publish Pro) to calibrate and profile your monitor.



For more information, please check out our website at www.nativedigital.com

4 Apr 2011

New videos about the X-Rite i1 Photo Pro

If you're keen to know more about the i1 Photo Pro, then these videos will give you a better understanding of the product and it's application.

The first video is just under 2 minutes and shows you the top 10 features of the i1 Photo Pro:




The last video is about US-based photographer Andy Katz - he show how he uses the i1 Photo Pro to help him throughout the photography process - from shooting RAW using the mini ColorChecker chart (to help with colour balance), profiling his monitors, profiling his printers and also profiling a digital projector - ensuring consistent and accurate colour every step of the way.



If you have any questions, please get in contact, or check out the i1 Photo Pro product page at www.nativedigital.com