[3dem] Cryo stage survey results

[Chris Arthur]

	I sent out an email a little while back asking about everyone's  
experience with different cryo stages (Gatan 626 v. CT3500). I  
received a few responses and just wanted to sum up the overall  
consensus. Let me preface this by saying that this is not in any way  
an endorsement or a criticism of either cryo stage or of Gatan. I am  
merely relaying information.

	The 626 seems to be a work horse type of stage. That is, it can  
accept a bit of mishandling without falling apart (not that you should  
ever mishandle your cryo stage), and may be the better choice if you  
are going to have a fair number of users. Most people seem to feel  
that it is a bit easier to load grids into the 626, and there are  
fewer incidences of problems with clip rings, although one person did  
mention a shutter problem with their 626. Everyone mentioned that the  
626 seemed to settle fairly quickly after insertion into the  
microscope and no one mentioned that drift was really an issue  
(although I am sure this is debatable). Only one group mentioned how  
long they could collect data before drift became an issue (roughly two  
hours, which seems a rather short period to me).

	The CT3500 received good reviews but there seemed to be a general  
feeling that it was a very fragile stage and was prone to mechanical  
problems. People seemed to be pleased with how stable it was, but most  
added that their CT3500 had spent some time in the shop. There was  
also the issue of price, the 626 is ~$37K, whereas the CT3500 is ~ 
$50K. This may be a deciding factor for some.

	I am not sure if this information is helpful, or anything new, but  
wanted to disseminate it to the EM community.




Christopher Arthur  Ph.D.
Staff Scientist
Milligan/Unwin Lab
The Scripps Research Institute
carthur at scripps.edu
858-784-7073