[nldunne]

Here is a color variation of the negative and normal image.
First I made 4 or 5 work copies of the original cropped version.
Next I did a small amount of tweaking on this cropped version.

Then I made a negative copy of the tweaked original to study high and low tonal values.
I would then assess my negative - saving it - as it is - or removing it and working on the tweaked copy further. If I removed the negative copy and did more tweaking, I would add a couple of tweaked work copies back in. When I am finished totally - I save the negative copy for reference and the tweaked copy of the original. I know this is slow, but it really points up how the exposure is.