Suddenly prints look dull (lacks contrast and blacks)

[lay9eggs]

Lightroom Version Number

Lr6

Operating System

1. macOS 10.14 Mojave

Hi,
I'm using Mac Os10.14.3, Lr6 and Canon Pro-1 printer.
Today, my prints did not turn out well. The images look dull - with poor contrast and weak blacks. So I printed an Evaluation Image which I had downloaded from Jose Rodriguez's site. The print colors and contrast look very close to what I see on the monitor. I compared this print with one of the same Evaluation Image that I had printed a few years ago and they look identical and lively. So, I do not think the printer has a problem.
Do you know if this is a problem caused by Lr or my MacBook Pro?
Recently, my Mac has been slow to boot, and today, before my printing session, I had to force quit to restart the Mac.
Looking forward to some help.
Thanks and much appreciated
Aaron

 

[Paul McFarlane]

Hi Aaron

What color space are you using? This can be the effect of you try printing AdobeRGB to a printer instead of sRGB

 

[lay9eggs]

Hi Paul,
I'm using sRGB.
Today I did some printing and it's back to normal. It's quite strange! I don't understand why. The last time I had something like this happened was after the Mojave update.
Thanks anyway
Aaron

 

[Paul McFarlane]

Hi Paul,
I'm using sRGB.
Today I did some printing and it's back to normal. It's quite strange! I don't understand why. The last time I had something like this happened was after the Mojave update.
Thanks anyway
Aaron

While not liking unsolved mysteries, 'All's well...'

 

[Scottd]

Do you always do a nozzle test before printing? It sounds like your black head was not firing from all nozzles. This would certainly cause results as you describe. The purpose of black ink is to add contrast to the colour. Any "black" parts of your image are made up of various combinations of C,M,Y, & K. If K (black) has dropped out, you will get muddy blacks and an overall lack of contrast.

Before printing, always do a nozzle test and clean as necessary.