CHROMiX

basICColor 5 Questions

Hi,

got a couple of questions regarding basICColor 5 that I am currently using with my i1Display Pro.

I created various profiles for 2 different monitors, using either L* (D65) or sRgb (D65) as tonal response curves with either Bradford or Cat02 (as chromatic adaptation), or a standard 6500K, Gamma 2.2, 120cd/m…

(1.) Out of all combinations or variations, the L* tonal response (recommended by basICColor) curve always ends up with the smallest dE values - and Bradford always scores better than Cat02…

Is this similar for you guys ? So, is this the response curve I should use ?

(2.) Regarding the target Luminance: one of my monitors has a max. luminance output of app. 189 cd/m2 - when I target 120 cd/m2 in the calibration I always get higher dE than the “sweet spot” I found (by trial and error) which is 160 cd/m2 for this specific monitor (giving me lowest dE)…

What’s general standard procedure for determining and specifying the target luminance for a monitor in the calibration setup ?

(3.) The software itself confuses me sometimes. When I get the final report after a successful calibration and I close the report, it goes back to the software interface showing again a few numbers of the just performed calibration - BUT: these numbers now differ (!) from the ones it just reported to me via the final report…

Why is that ?

Also, when I immediately run Validation after a successful calibration, the numbers will differ again… Is that because the i1Display Pro reports different values every time (b/c of heat etc.) ?

Thanks for your input !

  • M

(1) L* (pronounced L “star”) is a tone response curve that corresponds to human perception in a linear way. In other words, using this option, a change along the tone curve at one point should produce the same amount of change to your eyes as a similar change at another point. (There must be a simpler way to say that but I can’t think of one right now.) So it’s a good choice to make. The only reason to not choose L * is if you are wanting to calibrate your monitor to match another (ie: someone else’s) that does not have the option to calibrate to L*.

According the basICColor Display manual, the Bradford transform has a non-linear correction in the blue region. So while it might mathematically result in better validation numbers, you might see blues responding in an erratic manner. At least that’s what I gather from the manual. Personally, I believe the changes between these algorithms to be so small that it probably does not matter too much which one you choose as long as you are consistent.

(2) Your luminance should largely be determined by your ambient lighting conditions. Especially if you are calibrating your monitor to match a printer that is sitting next to your display, you need to set up your monitor so that it approximates the brightness of your printing paper. Read up on the “white paper test” mentioned here:

colorwiki.com/wiki/Printer_t … Paper_Test
colorwiki.com/wiki/My_Printe … e_of_paper

(3) I think when you talk about the final report you are describing the end of the validation process? Each time you do a validation you will see slightly different numbers. There should not be a large delta E result if you are running a validation immediately after you have profiled.

Keep in mind that the “validation” process in any monitor calibration system does not actually verify that your colors are accurate. All it does is check to see if the colors it is measuring after profiling match up with what it would expect to get when you originally profiled. Due to the smoothing nature of profiles and repeatability of measurement devices, you’re never going to get a validation that is 100% the same. In most cases, all this function is really telling you is “how consistent is my measurement puck?”

Great questions.

Patrick, thank you for your reply.

Just got my Eizo from you guys so now it’s getting serious :wink:

Generally, I do video editing (Rec 709) and some graphic design, VFX work.

regarding (1): I don’t need to match someone else’s screen, so I’ll stick with L*.

regarding (2): I’m still uncertain what to set the luminance value to. I don’t print, so I don’t need to match a printer. In basICColor I could simply set max / min and the software will determine the values, but I’m not sure if there is a general reference value. I remember 6500K, gamma 2.2 and 120 cd/m2 used to be reference values in the past.

So should I use 120 cd / m2 ? What if my screen can easily do 180 cd / m2 ?

Need advise here…

regarding (3): I understand that when I run the validation immediately again I will get slightly different values due to the meter. What I was talking about in the first paragraph of (3) is that, when you do a calibration and you get the overview report (you’re viewing the jpeg report that is saved on your HD for you) and you take a note of these numbers and go back to the general user interface, the screen will repeat some of the main numbers (of the report you just saw)… it’s just that these numbers are different (pretty close, but different)… and that is odd…

Another question I have specifically for the Eizo:

Obvioulsy I will now choose HARDWARE CALIBRATION (monitor LUTs) under presets in basICColor. Do I need to make a calibration for each monitor mode (REC 709, sRGB, EBU etc.) or will one calibration work for all of these ?

Thanks !

  • M

If you’re choosing Hardware Calibration, DO NOT use any other application for calibration and profiling your Eizo screen except for their very own software, Eizo ColorNavigator 6.11. This is far more accurate than anything else I’ve tried on the market, on my own Eizo CG242W screen.

As for screen brightness, don’t go above 120cdm as you will invalidate your backlight warranty. If you bougbht a ColorEdge screen, the 5 year backlight warranty is only valuid so long as the backlight brightness is kept at less than 120cdm.

I too calibrate and profile my screen to Lstar and use the following settings: BP 0.4cdm WP 100cdm depending on the paper I’m using, I might change the screen’s overall colour of white (WP) to between 5,500k to 6500k, usually it’s closer to 5700k or so. I always select Grey Balance Priority

Don’t waste your time using BasICColor Display or any other 3rd-party software to calibrate and profile your Eizo screen. You will be missing out on many features and functions which are only supported or offered by the Eizo application. Plus, they build the screen, they designed the ASIC chips which drive the screen and LUTs, so who could possibly extract better performance out of an Eizo screen but the very people who designed and built the screen?

Well, that’s my view in the matter and in the past 3 or so years, I’ve not found any profiling app which could better or really even equa the quality of Eizo ColorNavigator.

Just out of curiosity, which Eizo screen did you purchase and what hardware device are you using to calibrate and profile your screen? If not an i1d3, why not? :laughing:

@Aaron: thank you for your reply, great info.

I purchased the CG275W. Spoke to Pat from Chromix this morning, and he was very helpful and explained to me a couple of things regarding the presets which confused me.

I’ll be using my i1Display Pro for now for calibrating, but I’m about to get the basICColor discus which unfortunately is currently not supported by CN 6.1.1.3.

I have a couple of questions regarding CN calibration targets for the Eizo and started a separate thread.

Here’s the link: [one.imports.literateforums.com/t/eizo-cg275w-calibration-targets-for-color-navigator/991/1)

Thanks.

  • M

Just thought I’d add that I think it would be an incredible waste of yours or just about 99% of any person’s money to purchase a Discus if that person already owns an i1d3, and especially if that person already has an Eizo CG245 or CG275, with its extremely accurate built-in Swing thingy.

Dry Creek Photo performed some very thorough tests comparing both the Discus and i1d3 and found that although the Discus is indeed more accurate and has better repeatability than the i1d3, the differences are on the level of being either invisible or incredibly difficult to see.

They found that on average, the Discus might have been around 0.5dE2000 more accurate than the i1d3. 0.5dE2000 would be very difficult to see if the 2 colours were right next to each other. The fact that we are talking about this being the difference between the accuracy of one device vs another device, I firmly believe that to pay somewhere upwards of US$1000 vs US$250 for 0.5dE is absolutely ludicrous, even being on the virge of outright stupidity.

I say that in the nicest way possible. I don’t mean that you or anyone else buying a Discus is stupid, I’m simply saying that without an extremely good reason, and many of those, not just a single reason, what benefit or use is there in wasting SO much money on so little of a gain/benefit?

I’m not trying to say to anyone that BasICColor doesn’t make some very good products, both hardware and software, because they do and I use quite a few of them and they really a re a great company. I’m just trying to help you spend your money where you’ll receive the greatest return for whatever amount is outlaid. And that most certainly won’t happen if said money is outlaid on the purchase of a Discus, in your specific circumstances.

Aaron you wild man! What a great poster!
I’d like to add a bit of balance to this. While the Discus is certainly not for everyone, it does have its purpose.

Here are a few things to consider:
Long-term durability. The additional cost of this device has gone into quality materials, such as the glass filters which will not degrade over time like the plastics that other colorimeters use. There are certain high end users who want something that is built to last, not because you can’t afford to buy a new colorimeter every few years, but because you don’t want to have to guess as to whether your colorimeter is on its way out or not.

Accuracy. It has already been stated that the Discus is .5 (half) of one dE more accurate than the i1Display Pro.

Repeatability. In addition to raw accuracy, there is the question of repeatability. How consistent is this device each time you use it? Every measurement device has some basic margin of error when it comes to measuring consistency, and people often forget to add this into the equation. I have not found any published stats on repeatability on the Discus or the i1Display Pro, but our own tests show somewhere in the area of .6 dE for the Discus and perhaps .9 for the i1Display Pro.

All these very small errors eventually add up.
An accuracy error of .5 dE added to a repeatability error of .6 and suddenly you’re at a delta E of over 1.0 which is visible. That’s not counting a change in measurement due to temperature change - which, while very small on the i1Display Pro, is still (once again) bigger than on the Discus. This error will inevitably get larger as the i1Display Pro gets older, while the Discus is likely to retain its accuracy for much longer due to its glass filters and other workmanship.

None of these considerations add up to what most people would consider a big difference. But it’s a big world out there and as dealers, we have a perspective that puts us into contact with a wide range of users… those who want the best value for the money, and also those who want the best period. The people who need the best have legitimate reasons for doing so; they can be working in very exacting circumstances or simply have no time or patience for wondering if their screen is accurate or not. This higher-end customer is who the Discus was designed for.

There are also more considerations that just the quality of the hardware itself.

Third-Party Software. The basICColor software supports the Discus and just about every other instrument out there. Because of new X-Rite policies, if you buy an X-Rite version of the i1Display Pro device, you will not be able to run it on many of the common 3rd party software programs. They have changed the way they work their SDK in order for an X-Rite device to only work on the i1Profiler software. For those who like to have options, this can be a problem.

I think it’s cool that we have these devices now. It wasn’t very long ago that there was a real gap in the market for colorimeters that did what we needed them to!

Great thread guys.