hardware calibration etc and linux



hardware calibration is one of the few things that I cannot do with linux - linux is usually not supported by screen manufacturers.
does somebody happen to know if something is coming here? or are there already any alternative tools that are little known?
from my point of view this is important. I can only use the native color space of my screen if I use hardware calibration and the difference between adobergb and native is visible. I would not pass on this. so using Displaycal’s interactive rgb-adjustment instead is not really a replacement for hardware calibration for me.
another thing that I cannot do is updating the firmware of my lenses - I need the Olymups software for that. however I do not do that often.

thanks in advance for the feedback and regards from Vienna



(Mica) #2

By hardware calibration do you mean something like a spyder or colormunki hardware device?


(Graeme W. Gill) #3

I suspect what is meant is being able to set the displays per channel LUTs rather than the video card, and/or uploading matrix & tables or cLUT to make it emulate a particular colorspace.

The former can have advantages if your video path to the display is only 8 bit :- if your path from the video card to the display is say 10 bit (i.e. the 10 bit output of the Video card per channel LUTs is faithfully transported to the display, which is the case for VGA output to my ancient CRT, but may be a problem with some older digital connections), then there is actually not much advantage in using the display hardware.

The latter has no point in a general color management sense - you are much better off running the display in its native gamut mode and profiling it. That way you get the full possible gamut for source spaces that can use it.



No. I have a BenQ and I can only use native when using hardware calibration. There is no option to switch to native with the help of the OSD. It is only possible to switch to native with the Palette Master Element software. Native color space is larger than AdobeRGB.



BUT last night I google for “hardware calibration linux” and I found some forum discussions according to which Eizo has a version of Color Navigator for Red Hat Linux. Apparently they give you the software if you ask for it, but there are no public download links. They say, they have not tested the software on linux and they do not guarantee that it is working. But users say it works, at least with Red Hat.



Both Eizo and NEC provides their calibration software for Linux.
I have NEC EA275WMi at work and Eizo CS2420 at home and I can assure that they were calibrated using dedicated software on Linux.
Color Navigator, now updated to version 7 which is finally 64bit, is designed for RHEL. I managed to have CN 6 working on Ubuntu but for simplicity I used VM. It’s possible since CN uses USB to control display. I have obtained CN7 from Eizo distributor in Poland but haven’t got time to play with it yet.
One thing I really didn’t like in CN is that it is using Adobe AIR. It looks nice, but Adobe has long time ago abandon Linux. And yes, you need to ask your local distributor for a Linux version. It cannot be downloaded from web page.

SpectraView II for NEC can be downloaded from webpage but you need to purchase separate license to use it even if you have NEC display. It works smoothly on Ubuntu without any issues.

Don’t know the details but it looks like Spectra is more technical. There are more options, and calibration takes more time. But it may be that CN has hidden options I really didn’t care about.

Both tools are easy to use and straightforward.

1 Like

(Graeme W. Gill) #7

It’s broken then. There’s no point in a display with a larger gamut if you can’t access it, or if it can only be used to emulate a smaller gamut.


(Graeme W. Gill) #8

Yep - I guess they do some minimal Linux support for their “Hollywood” customers.



I was suspecting that this is for medical care rather giving the fact that CN was for 32 bit RHEL 6 but your’re right!



Recently I spoke with a friend of mine who has a Dell screen. Apparently it is the same with Dell. You can only access the native color space with hardware calibration resp. the BenQ software.
There are several color modes that can be accessed with the OSD, all of them except cal1-3 which are the hardware calibration modes are in AdobeRGB or sRGB or recsomething or dcipsomething or black and white.
I am sure that it is inetended to be like that. It is no “bug” in the OSD. It is also written in the documentation that the 2 “user” modes are also in AdobeRGB.



@gwgill OK I think this is a misunderstandig. I can access the native color space. But I have to do hardware calibration first. In fact now I am using Linux and the native calor space.
You do hardware calibration (with PME/Win), the calibration is saved in the screen as a “color mode”. I activate the color mode in OSD. Then I profile the screen.
If I do hardware calibration and select the mode “calibration xy”, I cannot change the settings of the screen such as contrast or rgb-values, which makes sense.
But every now and then I need to use PME for hardware calibration which is a Windows app.



I had Dell display once which supposed to have hardware calibration. What I learnt is that is just lock the settings and kept them at CAL1. There is no hardware calibration in Dell displays. That is the answer I got from people who professionally do the calibration (screen, printers and so on).



I do not understand what you mean. AFAIK Dell also has a calibration software. I know this because I was about to buy a Dell screen but I learned that the Dell calibration software only supports x-Rite devices. Why would there be a Dell calibration software if it does not do anything?
I mean in theory it is possible. You install the software, you attach the screen and the calibration device, you launch the software, the software recongnizes the screen and the device an then it actives panel native mode and locks the screen settings. And then it only does profiling actually.



The Dell software was as I remember re-branded X-Rite software. I was told that the whole marketing talk about calibration was simply overstatement, see here: https://mva.pl/viewtopic.php?f=21&t=3379&start=60 (use translation of course).


(Morgan Hardwood) #15

Maybe start by telling us which screen you’re using, linking to a PDF user manual, and defining what you mean by “hardware calibration”.



it’s a BenQ SW240.
I am kind of not looking for help here. It is just a discussion about the availability of screen manufacturer’s software for Linux.
I know what hardware calibration is. I kind of assumed that everybody here knows what it is.
So far it is indeed an interesting result that some important brands do “secretly” provide their software for LInux as well.



Yes indeed! I was confused because here and there Eizo mentioned Linux but no official statement. So I wrote to the distributor asking about it and they give it to me without any further questions :slight_smile:


(Morgan Hardwood) #18

It’s many things, so it would be good to start off with a definition of what you mean by it.

See page 42 of the “SW240 User Manual” https://www.benq.com/en-us/support/downloads-faq/products/monitor/sw240/manual.html :

Custom 1 Custom 2 Applies a combination of color settings defined
by users.

SW240 Data Sheet: https://gzhls.at/blob/ldb/c/e/3/6/e19cd14d9e98798cea135719f881ce828639.pdf



But OK, for those who do not know what hardware calibration is - although this is not easy for me in English: h.c. is basically when it is not the user who sets brightness, contrast, color temperature etc. with the help of the screen’s OSD and the buttons of the monitor but a software. You connect the screen and the computer with a usb cable, attach the calibration device, place it on the screen and launch the software. At the end of the process the software saves the settings in the screen and you can access the setting (which is usually called calibration 1-x) with the OSD, but the software usually activates it. If the “mode” is active, you cannot change brightness, contrast etc. But of course you can disable the this color mode and switch to “custom” or “AdobeRGB” or whatever it you want. Then you can tweak brightness etc.
But whether you use h.c. or not, you still need to profile the screen with a software such as Displaycal.
If you do h.c. there is no need to change the video card LUT or whatever it is called, i.e. do actual (software) calibration.



yes. But Custom1 and Custom2 are “only” in AdobeRGB. Believe me, I have the device. I know it.
Although it would be interesting(nice to somehow activate the native color space in custom mode. But I am quite sure that it is not possible.
Maybe I should just ask BenQ if they have the PME software for Linux.