Digital BW, The Print

Recently I printed some shots taken in Boston and the prints cried for a warmer tone. As I have had good success creating a curve that prints a neutral toned print on any glossy paper I have on hand, I decided to try and adjust this to print a warm tone on glossy paper. 

Essentially, I inverted the red and green channels in the .acv curve, leaving the blue channel alone. This worked well and gave a nice brownish warm tone. Further adjustments of all the channels made it even better. I tested it on Red River Ultrapro Satin and Arctic Polar Gloss. Both print with good ramps and no surface defects. All that is needed to use the curves is to apply them to your finished image using the curves > presets tool. Your image must be in RGB mode and the screen coloration of the image will change when you apply the curve. 

Scanned test images using the Keith Cooper Northlight test image, and the curve are posted at http://sdrv.ms/15bjfIq . I included in the folder my earlier neutral toned curve, formerly called RRAPG_neutral_2.acv, which I've renamed for clarity. The two curves are now:

UT14_gloss_warm.acv and U14_gloss_neutral.acv. 

I have tested the neutral curve with Red River Ultrapro Satin, Arctic Polar Gloss, Polar Pearl Metallic. All print well with no surface defects. I did not try the warm curve on Metallic paper, but am pretty confident it will be fine. I suspect these curves will work well on any glossy paper with the UT14 ink set.

I have noticed an issue with applying the curve to images opened out of Lightroom into Photoshop. There is apparently some kind of color information in the file that corrupts the curve, or at least causes it to display and function improperly. The following steps resolve the issue: 
 
When your grayscale conversion is complete in Lightroom, right click and open the image in Photoshop. Convert the file to grayscale using the Image>Mode commands. Save the file  (as a .tif or .psd) and close it. Reopen the file from within Photoshop and convert it back to RGB mode. The curve will now apply correctly.  
 
The symptoms of the problem are this: When (the warm) curve is applied, it should turn the blacks deep blue and the mid tones shades of purple. Straight out of Lightroom, the image will have blacks as black and the tones of gray are shades of purple. Printing, when the image is in this mode, will have overly dark blacks and significant surface issues. With the file-save and re-application of RGB, the image prints correctly with no surface defects.