Experiments with painting rocks

I left the rocks and cliffs on the mountain painting incomplete. I set down their placement to my satisfaction, but I do not like the contrasts within the rock itself -- that is, the cracked lava filter produced too much sparkle. To the right, I have outlined one technique in its various steps that I plan to try on the painting to achieve several benefits. The benefits that I seek include the ability to draw rocks over larger areas and then to trim them to the actual shapes that I see without having the filter effect change. You will find, as you experiment with Inkscape filters, that moving and resizing an object to which you applied a filter changes the filter's effect. Another benefit that I seek is to use a filter, but to change the contrast of the effect without altering the effect itself. In this case, I wish to lessen the sparkle and but keep the the effects of ridges achieved by using the filter in the first place. Finally, I wish to apply blurs and or gradients to objects which contain filter effects without changing the shape of the effect -- I want to affect only the filter effect's contrast with its surrounding objects. I have complained about ghosting when blurs are applied to filtered objects in another post on this blog (river with newly fallen snow), so I really am using this feature enhancement on one painting to solve a general problem that I have run across in other paintings. Finally, I have used the technique described here before with success with other filters (watercolor-style painting of river), so I wanted to see whether it would work as well on the cracked lava filter. It looks promising. Click on the illustration to see a larger version.