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<DIV><FONT face=Arial size=2>Dear list members,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>in the book 'Polymer Microscopy' by Sawyer and
Grubb I read about a rule of thumb relating</FONT></DIV>
<DIV><FONT face=Arial size=2>attainable resolution to the specimen thickness
(about 1/15 of the thickness for carbon specimens</FONT></DIV>
<DIV><FONT face=Arial size=2>imaged with 100 keV electrons).</FONT></DIV>
<DIV><FONT face=Arial size=2>The authors refer to the second edition of Reimer
but I can't find this statement in the fourth edition</FONT></DIV>
<DIV><FONT face=Arial size=2>anymore.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>How seriously should this rule of thumb be taken
for TEM phase contrast imaging?</FONT></DIV>
<DIV><FONT face=Arial size=2>Does anybody know of a publication giving estimates
for different electron energies and specimen</FONT></DIV>
<DIV><FONT face=Arial size=2>thicknesses?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>On pages 190ff in Reimer 4th ed. I found a
discussion of the 'top-bottom effect' in STEM with</FONT></DIV>
<DIV><FONT face=Arial size=2>some references to publications on similar effects
in TEM and energy-filtered TEM.</FONT></DIV>
<DIV><FONT face=Arial size=2>Would the resolution in a TEM phase contrast image
depend on whether the specimen</FONT></DIV>
<DIV><FONT face=Arial size=2>is above or beneath the support film?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thankful for any comments and
references,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Philip</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Philip Koeck<BR>Södertörns Högskola
and<BR>Karolinska Institutet<BR>Dept. of Bioscience at Novum<BR>S-14157
Huddinge<BR>Sweden<BR>phone: +46-8-6089186<BR>fax: +46-8-6089290<BR><A
href="http://www.biosci.ki.se/em">http://www.biosci.ki.se/em</A></FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>The phrase 'We have always done things this
way.'<BR>is as much a reason to change as a reason not to.<BR>- Dartwill
Aquila<BR>_______________________________________</FONT></DIV>
<DIV> </DIV>
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