Modérateurs: Modération Forum Home-Cinéma, Modération Forum Installations, Modération Forum Univers TV, Le Bureau de l’Association HCFR • Utilisateurs parcourant ce forum: Aucun utilisateur enregistré et 13 invités

The New Lumagen 125-Color Calibration Technology

Message » 07 Sep 2012 16:55

Chromapure

Précisions concernant les sondes conseillées

tom huffman a écrit:BTW, I should have mentioned, anyone opting for this should be using a fast and accurate meter with good low-light sensitivity, such as the Display 3 PRO, Hubble, or K-10. If you try and do this with a Chroma 5, Display 2 or i1Pro you either won't get the desired results or you may get them after the 2 hours it takes for the process to complete. I would also recommend not using a reference spectroradiometer either. Each calibration may take 600-700 readings. That's the best way I know of to wear out a shutter.


Précisions concernant le Gamma à 2.22
tom huffman a écrit:The rest of auto-cal is the same.

Actually, it is not advisable to set a higher standard gamma for auto-cal (and certainly not a lower). If you run a standard power law gamma much higher than 2.22, then you will get poor shadow detail. Running a higher gamma above 40% and a lower one below is fine, but that sort of fine tuning should be done independently of auto-cal. We may implement BT.1886 in the future builds, but my inclination is to leave auto-cal at 2.22, as that is a good compromise for most systems.
realzven
 
Messages: 10439
Inscription Forum: 13 Mar 2010 15:19
  • offline

Message » 11 Sep 2012 12:46

Une petite explication de Jim Peterson, le président de LUMAGEN: http://www.convergent-av.co.uk/forum/in ... #msg_19273

Jim Peterson a écrit:To my knowledge, all consumer level displays/projectors use the HLS color space for CMS. The HLS (or HSL if you prefer) is a non-linear color space and so is not mathematically correct for this calibration -- it's just easier to implement, which is why it is used I suspect. This means that even with a display/projector with linear response, using HLS color space means only the calibrated primary/secondary points are correct. Points in between are not correct.

The Radiance 8-point Gamut CMS uses a linear-Gamma RGB color palette. This means that if the display/projector has a linear response it can do an excellent job of calibrating CMS. However, if the display/projector has a non-linear response, such as red-push or green-push, interior points in the color cube need to be adjusted for correct response. With the 8-point Gamut, one can use Color Hue and their offset to mitigate red and green push, but this must be done by eye looking at real material since there is no easy way to automate it. It is tough to get this just right.

The new 125 point (5x5x5) linear-Gamma RGB color palette can correct for this and other non-linear responses, and should certainly give better performance than anything available in a consumer projector or display.

Note that the Radiance 11/21-point Grayscale is calibrated first. Then the 125 point CMS palette is calibrated. They are logically in series with the CMS first followed by grayscale
alex_t
Membre HCFR Contributeur
Membre HCFR Contributeur
 
Messages: 10852
Inscription Forum: 29 Oct 2005 23:04
Localisation: Ile-de-France, 77
  • offline

Message » 11 Sep 2012 14:10

merci alex je vais mettre l'info en page 1 :thks: :wink:
realzven
 
Messages: 10439
Inscription Forum: 13 Mar 2010 15:19
  • offline

Message » 14 Sep 2012 10:05

des infos dénichés par alex_t (merci à lui :thks: :wink: )

alex_t a écrit:Il est là :idee: :thks: (pour le XD ici: http://www.lumagen.com/testindex.php?mo ... ce_updates )

Beta 090412- NEW 125 point CMS added! That's a 5x5x5 matrix for color correction and calibration. A big upgrade from our previous 8 point matrix which allowed calibration from only the corners of the color cube. The new 125 point gamut has it's calibration points located at 0, 25, 50, 75,100% of video min/maximums. The older 8 point gamut was located at digital min/maximums which did not give quite as much precision. Previous calibration values in the CMS gamut menu are interpolated to the new gamut locations so the numbers displayed in the menu will be different. This doesn't change your previously performed calibration results. Instead, the changed values represent the same calibration but from the new gamut locations. You now have the option of calibrating with 8 or 125 points. If you perform an 8 point calibration you can change to the 125 point mode and keep the previously set 8 points. The other 117 points are interpolated from the original 8 when changing from 8 to 125 point mode. With this many points to adjust, auto calibration software from ChromaPure and SpectraCal really helps. They have both added support for our new 125 point gamut with excellent results. Note: We are in the process of updating the Configuration Utility to support backing up the new 125 point gamut data to a PC via rs232. This should be available by tomorrow.
Gamma correction: Range has been extended and can now be adjusted in steps of .01.
Test Patterns: Added 2.35 letterbox geometry overscan pattern.
Bugfixes,etc: Problems with Top/Btm 3D formats to Frame Packed and Frame Sequential output was fixed. An issue of using test patterns with certain settings not restoring the input aspect was fixed. Improvement to output setup menu allows multiple changes within the command to be performed more easily. Added sending 601/709 color information needed by Darbee Darblets with firmware before 2.8.2214. Added a direct command to globally disable video on output 1, "menu 0985". Other small fixes and improvements were also made.


Quelques détails sur l'implémentation de la mise à jour :o , source: http://www.convergent-av.co.uk/forum/in ... #msg_19282
Jim Peterson a écrit:You do not need to wait until your next calibration to update to the 5x5x5 software.

Patrick spent a lot of time making sure old 8-point, and grayscale, calibrations yield the same calibration points (RGBCMYW, and 11/21 grayscale calibration points) using the new 5x5x5 software. Note: If you did find any issues, you could always go back to older software and your old data will still be intact.

The new 5x5x5 CMS release uses the 5x5x5 FPGA-hardware for the 8-point CMS calibration. So, the software does need to interpret the old 8-point data and apply it to the new hardware. While this means there might be a very small chance of a significant measurable difference, we do not think there will be.

That said, there is an advantage to using the new 5x5x5 software with your old 8-point calibration. The new hardware has higher precision, and the blend of Grayscale and CMS has been improved. So while you should get the same measured calibration points, the image color accuracy will improve with the new 5x5x5 software using your old 8-point calibrations.

=====

Credit where it is due: On the Lumagen side this improvement was due to Patrick's efforts for both software and hardware. While I did have some input on architecture, Patrick spent nearly a month (possibly more. I am not sure) on optimizations to allow this to fit in our FPGA, and on the actual implementation, and deserves the lion's share of your praise for the new 5x5x5 CMS.

And again thanks to both Spectracal and Chromapure on there input, software development, testing and feedback on this exciting new feature.


La méthode pour calibrer, source: http://www.convergent-av.co.uk/forum/in ... #msg_19284
Jim Peterson a écrit:Because the new 5x5x5 FPGA hardware works differently than the old 8-point calibration, there is a new order of steps for calibration.

Here is the new best practices order:

1. Set display controls to neutral and turn off all special features in the display (including dynamic-iris).
2. Set black level display controls. Use Radiance Dark-PLUGe for black (go to contrast pattern and press number 4 on remote).
3. Set white level in display being careful no color channel is crushing. Use the 2-white/2-black box contrast pattern and others.
4. Set 100% white color-of-gray in display using appropriate sized window pattern, if available.
5. Check Gamma and use Gamma factor for coarse Gamma adjust.
6. Recheck black and white and again use display controls to adjust them if Gamma factor changed them.
7. Calibrate Grayscale/Gamma with 11/21 point. Note, once any CMS entry is changed, do not tweak any grayscale entries!
8. Use CMS white point to reduce 100% white Luma only (R=G=B), if needed, such that RGBCMY have enough Luma.
9. Calibrate other CMS points.

This sequence works for both 8-point and 5x5x5 in the new software. The old procedure does NOT work properly with the new 5x5x5 software. Old 8-point CMS data does get interpreted correctly with new software as mentioned in previous post.

[EDIT] Interestingly, this new calibration sequence works with old software.

We will be updating our Tech-Tip 2 on calibration with the information soon.


source: http://www.convergent-av.co.uk/forum/in ... #msg_19285
Randy Freeman a écrit:The new Beta Software has been posted!

When you update your software, the old calibration will be accurately mapped into the new color cube. This feature has been tested by a group of beta testers.

Randy Freeman
Lumagen



MERCI A LA LUMAGEN TEAM 8)

(reste plus qu'à tester maintenant)
realzven
 
Messages: 10439
Inscription Forum: 13 Mar 2010 15:19
  • offline

Message » 14 Sep 2012 10:07

j'ai mis à jour la page 1 :wink:
realzven
 
Messages: 10439
Inscription Forum: 13 Mar 2010 15:19
  • offline

Message » 14 Sep 2012 14:23

:D les 1ers retours US sur AVS Forum avec Calman 5 et Lumagen

As we are now released from NDA, I just wanted to post a copy of my last (as in most recent, not the very last I hope:)) post in the Calman 5 beta forum. I'm sure results will vary depending on each display and user, but as far as I'm concerned, I couldn't be happier. And those who know me know I'm not easy to please... Here we go:


Just wanted to say thanks again to Spectracal and Lumagen for this breakthrough. I've just done a new calibration with a 2.3 target (my usual target in my bat cave) and the results are nothing but spectacular on screen.

It is by far the best my rs45 has ever looked, both regarding color accuracy and dimensionality/shadow detail.

Having both the right chromaticity and gamma at every level is just spectacular, especially in scenes with low light.

I went through a series of clips I know really well, and the level of detail is simply incredible. Some colors which used to suffer from the necessary compromises in a manual calibration are fully restored.

Well done again!


Ps: I'm using a Lumagen radiance mini with the latest beta f/w, an i1pro2 as a reference meter and an i1display Pro as a field meter. I do a basic calibration before hand, especially setting the gains at 109%, but all the hard core work is done automatically in 45mn by Calman pushing 2 buttons.

Sent from my iPad using Tapatalk HD


Thanks, Joel. It works like a champ. With the revised workflow I LUTed my 65VT50 and the results are excellent. After first watching some reference content I added a Darblet between the Radiance and the plasma. 40% Darblet is now doing what 55% used to do. I'm presently watching today's Sprint Cup race I recorded and am pleased to report I'm watching the best picture I've ever seen. Kudos, guys.

realzven
 
Messages: 10439
Inscription Forum: 13 Mar 2010 15:19
  • offline

Message » 04 Oct 2012 12:07

Une révolution sans aucun doute, mais elle n'a pas l'air d'enthousiasmer les foules vu le peu de compte rendu publié dans le monde francophone.
C'est un peu dommage.
kerlucun
 
Messages: 1671
Inscription Forum: 28 Juil 2002 10:17
  • offline

Message » 04 Oct 2012 13:01

kerlucun a écrit:Une révolution sans aucun doute, mais elle n'a pas l'air d'enthousiasmer les foules vu le peu de compte rendu publié dans le monde francophone.
C'est un peu dommage.


Ou alors c'est comme pour les cantines, quand c'est bon plus personne ne parle.
alex_t
Membre HCFR Contributeur
Membre HCFR Contributeur
 
Messages: 10852
Inscription Forum: 29 Oct 2005 23:04
Localisation: Ile-de-France, 77
  • offline


Retourner vers Les logiciels de calibration