Got gray card (an actual 8x10 18% gray card) and metering is now showing 1/6 second instead of 1/30... that ought to do it!
It certainly should. That is over 2 stops from the previous method.
How much quicker was it to actually correctly measure it rather than experiment?
If you stood ten people in a row and asked them to compare the brightness and colour of two objects then you would get 20 answers. The human eye is notoriously variable. It depends on the person, the time of day, how they are feeling etc. There is a famous post where people were asked the colour of a dress, blue or green with varying results. Subjectivity has no place in art reproduction. Fortunately a technical approach will always work.
If you go from correctly exposed with correct camera calibration and scene calibration through to correct print calibration then it
should be right.
At least if it isn't then you have a process that you can go back and review and find out where you went wrong or introduce a controlled subjectivity. You have a repeatable process.
The one thing which is completely out of the equation and which everyone spends so much time on is monitor calibration. If the numbers are right then you can ignore the screen. It is not in the path. Cheers.