Neutral hard to get

Hi Walker,

I’m struggling a bit at getting a good neutral curve on the Photo Rag 308 with the new cool ink formulation.

Lighter tones are warm and the darkest tones are cool, it looks like a split but it’s not.

See the values.

What do you think ?

It’s actually a blended curve with 35% Warm.

Best,

Frankie

PhotoRag_i1Profiler_i1io_256_Neutral_M0.txt (7.5 KB)

I think maybe you need to re-do this with closer to 25% warm in mid/hLs. You can do this simply in the sliders in QTR if you are making a “neutral” just with the Warm and Cool curves. Or you can use the stock cool curve and simply tune it warm or cool in Highlight/Mid/Shadow with the sliders in QTR. This can be your reference setting for building a “hard-coded” neutral curve with the PPEv2 tool later on.

Also, always measure in D50 mode too. ColorPort exports data by default in Illuminant A (not d50).

Also, the very base shadows always go a tiny bit warm due to 100% carbon at the end (most archival and darkest black).

Neutral is always the a hardest to achieve . . . . .

best,
Walker

I think the only option is to split yes… not the easiest part !

D50 is okay, I double checked it, now using an i1io and i1Profiler, much quicker than measuring by hand.

The stock neutral you made was already a split looking for neutral or just a basic blend with the same % on all tones ?

Best,
Frankie

The stock for this printer/paper was a slight split as a recall. It was several years ago so I’m not sure if I remember correctly.

-Walker

I’m actually testing some splits to “linearize” the cool/warm for all the values.

I’m trying to match a Lab b ± 1 to get a bit of warmth (don’t like the perfect neutral so much).
I get something approximately good but needed to do a huge split to get this result (29-31-80 in Print Tool).
The cool tones seems to be very blue so I need to push the warm% very high on the shadows.

Do you think this is kind of “normal” ?

Best,
Frankie

29-31-80_M0.txt (7.5 KB)

Yeah. Because the “B” is negative on the paper base itself, and because there is less “color” in the highlights, larger swings would be needed to perfectly neutralize.

-Walker

12.70 L* on the dMax. :sunglasses:

I understand yes, thanks for the explanation.

The black is so deeeep yes, I like it ! :slight_smile:

Any idea how I can now replicate this curve to make it a “hard curve” in PiezoProfessional ?
I need to blend the cool & the warm but I need to put 7 values and only get 3 in Print Tool.

29/29/29/31/80/80/80 could work ? (I’m at 29-31-80 in PrintTool).

Best,

Frankie

you need to slope it evenly for 29 to 31 and then 31 to 80.

-Walker

The PrintTool values are the extremes ?

Like this ? (then I need to complete them in the Blender)
RGB 255 = 29%
RGB 128 = 31%
RGB 0 = 80%

yeah. SO for the the other ones in-between they should be sloped (% amount).

I will upload a screenshot when I get the chance. If you don’t figure it out.

29/29/29/31/80/80/80 makes a very steep move between the 31/80. You need something like 29 30 30 31 65 75 80

best,
Walker

Perfect, I’ll do this.

Thanks Walker !

Update : the blue shift is completely gone, nothing has changed except that I did some print tests.

It’s really strange !

@PiezographySupport Can you send me a .txt file with the LAB data of a 100% cool target you already measured so I can compare the blue values ?
That would help me figure out if my cool inks are ok.

Here are the papers I can measure to get a comparison : Hah PhotoRag308, UltraSmooth, BrightWhite, Museum Etching and Fine Art Baryta.

Thanks !