Thanks for having a look guys.
Armand - yes the 3rd one is a bit soft. I'll have another look at it.
Bob - Nothing special at all. These are just shot on the window of our greenhouse. The trick is to get the right conditions to produce the nice crystals. See comment below.
Scott - The problem with this type of shot is finding a pleasing composition and then getting everything lined up with the focal plane parallel to the window when very small movements of the camera change the composition a lot. Rather than fight that. I find it easier to get a nice composition and then focus stack. I've missed too many going the other route. At 130 mm effective focal length (on a APS-C sensor) the dof is very small.
Chuck