Soft Proof Preserve Numbers?

[larryjb]

When preparing black and white prints for Piezography (see https://piezography.com/about/the-piezography-process/ ), the soft proofing must be done using "preserve numbers". In Adobe Photoshop, this causes the soft proof to use "Assign" rather than "Convert" for the soft proof. This is required because printers for Piezography replace the colour inks with inks of different shades of black/grey, so Piezography users have used the "Preserve Numbers" for soft proofing so that fine details in the darkest blacks don't get clipped. Corel PhotoPaint does appear to have this "Preserve Numbers" (http://product.corel.com/help/PHOTO-PAI ... ingle=true ), but this program is far more than I need and is very expensive.

Is there any way to get a Preserve Numbers in Corel Aftershot? This would be very helpful.