Converting K7 SREL to PK HD


#1

Hello,

I am following Walker’s instructions to convert my K7 SEL set to HD PK to be able to use the HD PK Master curve on Museo Silver Rag.
Before Ordering I wanted to make sure I understood correctly and was ordering the right items.

I intend to replace the MK “neutral shade 1” with HD Matte black and the PK “Warm-Neutral shade 1” with HD Photo Black.

Should I also replace the “Gloss overprint” with Gloss Chromo Optimiser?

Do I need to buy new refillable cartridges or is there a way to empty and clean the cartridges?

Will I be required to purchase the Piezography Pro software to create a curve specific to this arrangement or will I be able to use the HD PK Master curve out of the can?

Thanks

Paul


#2

Dear Paul. Please see my previous msg here: https://www.inkjetmall.com/tech/showthread.php?2796-Converting-K7-SEL-to-PK-HD


#3

Hello Walker,

I received the HD ink and have started testing with the HD PK Master curve. My i1 is old and the readings may not be accurate but I think they are consistent and should indicate relative values. The HD PK Masters curve works very well with the HD ink on Jon Cone type 5. It brings Dmax to around L4.4 from L5.8 (and maintains a barely perceivable threshold at level 2. The Museo silver rag however is too dense for this curve, its Dmax is 2.5 and the first barely visible line is around level 16.

I am assuming that the piezo pro software will allow me to pull back the black ink, (or shade 2&3) to lower the threshold. Is this right?

Could I also hear your thoughts on applying a traditional (colour managed) fix to this problem? If I were to apply a black point target adjustment to the file, effectively reassigning the data to maintain DMax at L*2.5 and bring the threshold to level 2 or 3, what would I be compromising when compared to a proper piezo pro curve relinearization?

Paul


#4

Yes. The PPE workflow will enable you to linearize shadow details for paper that requires a larger ink separation (Epson Exh. Fiber).

Best,
Walker


#5

OK thanks, I realize the piezo pro software would be the best scenario.

I have the feeling though that the master curve is just sending too much ink to the Museo Silver Rag. I lowered the shadow ink level in the GUI interface and this had no effect on Dmax, which seems to confirm my suspicion. The same shadow ink adjustment lowered the threshold considerably. Can the Master curve be modified to better suit a specific paper by reducing the shadow ink level this way and still maintain the same tonal transitions from cartridge to cartridge?

Paul


#6

Yes. Using the blender tool with your master curve in the “cool side” and a “null-set” curve on the “warm side” side can let you limit the curve in any way you see fit from dark tonalities to light tonalities.

Longer discussion in the private forum (for PPE) at Piezography.com

best,
Walker


#7

Great!. Thanks for the reference ,

Best Regards

Paul