[Nexus 5 General] yorici:
Oke, let me get this clear:

Purpose:

HCFR: Do measurements

N5 app: Edit parameters to adjust colours.

Spreadsheet: Get the value it should be.

So what you do is this:

In HCFR you measure each time 2/3 sets of value: The parameter you want to correct, White (255,255,255) and if you want to be even more precise Black (0,0,0).

Example:

Let's say you are going to correct value 5 red. You fill in White (and optionally Black).

Goal: 6500K + 2.2 gamma

Measured: White: 420, 5th red: 400,1 (and Black: 0,4)

The recommended value is then 398,586. Now take this roughly 398,6. You are 400,1 - 398,6 = 1,5 off. I think you can do better than.

So what do you do:

The fifth parameter of red is too high.= so normally you decrease the value

BUT, in your case, the app still uses reversed values, so you must increase the value in the app (to actually decrease it).

You measure All 2/3 values again, not just the fifth again.

Measured: White: 432,1 , 5th red: 410,1 (and Black: 0,4)

Fill White and Black (black again optionally) in. Recommended value 410,068 aka 410,1

So you are spot on!

Basically it comes down to this:

Set goal (i.e: 6500K and 2.2 gamma)

Measure White (255,255,255)

Use spreadsheet to get recommended value for White

Compare to measurement and correct using an app (Like N5 Gamma App of FKU)*

Repeat steps 2 to 4 until correct

Do the same for Black (0,0,0)

Measure White + Black + Other parameter (ie 2nd Red)**, ***

Use Spreadsheet to get recommended (So fill in White and Black and read the recommended value for 2nd Red)

Compare and correct using an app

Repeat steps 7 to 9 until satisfied with result

Repeat it for every remaining value. (Usually best practice to do 3rd now, then 4th, then 5th, etc.)

*For N5 Gamma App: The first 12 values are reversed: So and increase == decrease and vice versa.

** Usually the gained perfection to measure black is not great for the first 14 values. I recommend using the Shades of Grey (Recommended). Saves a bit of time, but still perfect enough.

*** You have the option to calibratethe 2nd value for Red, Green and Blue at the same time (usually results in more perfect color temperature) or calibrate only the 2nd of Red and then continue to 3rd of Red. So you first calibrate all red, then green, then blue (usually results in more perfect gamma)

- I'm looking at the pics in the (recommended) folder: when I do a free measure of "a-p1" and insert the values in the spreadsheet, should I use these values only to tune the firse parameter in N5 app, and ignore the others?

Similary, when I do "c-p2" I should only care for the "value2" of the spreadsheet?

The pictures are sorted in the right order so you only need to swype. The "a-" is in front of it to get the right order.

As partially explained above: I calibrate in a certain order: First White, then Black, then 2nd Red, then 3rd Red. The pictures are arranged like that. So for step 2 you use a-p(1) - RGB(255,255,255).png (Full name) solely. For step 6 b-p(24).png. You only move on when you are content with the result.

For step 7 you use the next two/three pictures: c-p(2) and RGB(255,255,255) (and optionally Black). After you are done with those, you move on to d-p(3).

- How to change color temperature? Since when R=G=B temperature is 6500, which values make the temperature increase anda decrease?

Colour temperature is like a ratio of Red, Green and Blue. When they are all equal, they are 6500K (or 6504K to be exact). If you want 6500K, you should keep all of those the same. But there are multiple options to get 7000K, your choice.

Red usually decreases colour temperature and blue increases it. Green is a special here. It decreases ultimately, but very slowly.. I recommend keeping green between red and blue, if not equal.

Hope that answers enough. Ask any question you like!