Negative-Spider Phase (Album 2)
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faint spider_302s65 "Go to Larger Image" Negative spider in deeper material
You can see the various depths that the streamers will penetrate to clean material away but this is just half of the discharge process. Material has the potential to be deposited back to the streamer paths and if that happens it will be piled tightly along the center of the path.
Negative/positive spider
Faint spider in center of image.
Here is a spider that is partly negative and also has developed a positive aspect. You are seeing a transitional period in the actual discharge yet some additional post discharge deposition may occur. The positive aspect (in this case) most likely formed during the pullaway phase.
The material was very thin so this spider is tough to see. Click on the image to go to a larger version.