Gatan Camera vacuum leak

[Shi, Dan (NIH/NCI)]

Bob,

If you don't need high quality image from the CCD, you could try to warm up
the CCD overnight and leave it at room temperature for recording image, it
might be able to get ride of trapped water on the camera. Otherwise, you
could try to warm up the CCD before you change your plates to see if it
makes the vacuum better during inserting the camera. If both methods don't
work out, you may need to call Gatan to check any leak on the seal O-ring or
on the metal box (most unlikely).

Good luck.

Dan Shi
NIH/NCI Lab of Cell Biology
  

-----Original Message-----
From: Bob Grassucci [mailto:bobg at wadsworth.org]
Sent: Wednesday, March 10, 2004 5:26 PM
To: tecnai at wadsworth.org; 3dem at ucsd.edu
Subject: Gatan Camera vacuum leak


Hi All,
	We have run into a reoccurring problem with our 2K Gatan CCD camera
on our 
Tecnai F20.  When the camera is inserted the vacuum degrades by about 10 
log units in the projection chamber.  We sent it back to Gatan and after 4 
weeks it was returned with the problem not fixed.  They suggested we slow 
down the insertion to approximately 20-30 seconds.  We did this by 
adjusting the pressure from the red brake line.  This only partially helped 
(now it jumps 7 log units) but it made the ccd camera much less user 
friendly.  We hesitate to leave the camera inserted because most of our 
data is collected on film and we do not want to drop any "stuff" on the 
camera.  Has anyone experienced a similar problem and if so has Gatan found 
a better solution that you can share?  I would appreciate any input.  Thank 
you.
	Bob

Robert Grassucci
Howard Hughes Medical Institute at The Wadsworth Center
Empire State Plaza
Albany, NY 12201-0509
Phone: (518)474-5821
Fax: (518)486-2191
E-Mail: bobg at wadsworth.org