I worked yesterday on cropping this image of Lichens in to a square format. I printed on a cold tone paper semi-matte and warmtone papers in gloss and semi-matte. I found it easier to get a print that pleased me on the warm toned paper but felt the cold toned paper made the image look flat no matter what contrast filter I used. I tried a split filter technique where I make a test print of various exposure combinations with the highest and lowest contrast filters. First I draw a series of lines on the vertical and horizontal over the photographic paper to make a grid of fairly even squares. I'll start with the lowest contrast filter and do a series of exposures in increments of say 5 seconds each going from top to bottom of the paper, then switch to the highest contrast filter and do another sent of overlapping incremental exposures moving from left to right. I will end up in one corner with the minimum equal exposure using both filters and in the opposite the maximum equal exposure using both filters everything in between will be a variation of different exposures using the highest and lowest filters. When I've finished making the test print I look over each grid and see where I find the nicest range of tonal values and figure which exposure combination it is. Then I make a print using that combination. I'll use that as a starting point and make various prints adjusting the exposure combination until I make a print I like or give up in frustration. In this case the top print done on cold toned paper was made with an exposure of 22 sec using a 00 filter and 14 sec using a 5 filter. The warm tone print was made using a 45 sec exposure with a 2.5 filter. I made the prints using an aristo cold light for use with variable contrast paper and my 50mm el-nikkor lens on my Omega D-2 enlarger.