NRAMM Discussion Forum

We get leopard ice forming on specimens with any detergent in them after a few hours in the new F20. Does not seem to occur on other F20's nor Krios or Talos.
Baffling.
FEI did ice growth tests (see attached pdf) and concluded:
- Using the dry grid, the ice growth rates of both holders T3 and AMI#2 are within FEI's specification (0.7nm/hr).
- Using sample w/ detergent, the ice growth rate of holder T3 is 0.8nm/hr, and after 7hrs the images show leopard skin ice.
- Using sample w/o detergent, the ice growth rate of holder AMI#2 is 0.01nm/hr, and there are no leopard skin ice shown after loading grid for 2hrs and 8hrs. I took 8hr-images at 4 different gird squares. Also I put 100e/Å2 (which should burn away leopard ice if there's any) on the same area, and the image shows no difference with the 20e/Å2 image.