Ok that makes a good bit more sense! So lets say I'm printing a somewhat low lit picture of a large old house with plants and ivy growing up the side. I want to get a lot of detail from the bricks, ivy, windows etc. I find my optimal exposure is 20 seconds. I could use a higher number filter (more blue) to really burn in the detail without making the subtle transitions in the shadows fill in. I could then come back and finish the rest of the exposure time with a lower number (more green) to help with the subtle detail.
Originally Posted by Ghostman
Or, say I just want a really high contrast print...because thats my "artistic" vision. I can get my basic exposure using a 2, then just dial it up to obtain a higher contrast?