Rock samples

You might remember I did a sketch a few posts ago that I said was for a piece I am working on.

Well, I have tranferred this to fabric - bu sketching out and painting it and have begun my thread painting.

So far, I have only completed the dark areas and will next be working on the moss.  But before I start with the moss, I need to get my colour samples sorted out.  I wanted to use whipstitch to get some spotting  within both the brown areas and the green areas.

Above you can see my first sample.  My idea was to begin with the brown areas, but to use a second colour in the bobbin to give depth. I started using a  circular zig zag. with brown thread on top with green in the bobbin.  You can see in the top part of the sample that the green bobbin thread is coming to the top.  This is called spotting (see Encyclopedia of machine embroidery, or Beginner's Guide to Machine embroidered Landscapes)
What I am looking at here is the tension I need to get a good level of spotting with the bobbin thread.  (I know this is something we like to avoid in quilting and general sewing, but in thread painting, it is a very useful technique)
Each sample has been tried at two different tensions, the bottom one where the top and bottom tension were close to equal and the top one where the top tension is much higher.
I felt that the brown and green, although the green spotted well in the top sample, were not quite right, so I tried  brown in the needle and yellow in the bobbin.

 This also gave good spotting and was more like the way I wanted the brown areas.

I also tried samples are using granite stitch  with straight stitch

 As you can see above, the granite stitch, I think looks more like moss and still spots really well with the green (left) and the yellow (right) in the bobbin.
I am sure I will use both of these combinations in the moss on the rocks.
The next thing I looked at was spotting on the green for the main moss areas.

As you can see, I have green thread in the needle and the bobbin threads are yellow (left) and brown (right).
both of these will be excellent to use in the mossy green areas.
So I have my colours and tensions worked out and can start my moss.  Of course I will also use other colours, but these three will form most of the moss on the rocks.