[3dem] more on the odd CCD image

Morgan, David Gene dagmorga at indiana.edu
Thu Feb 4 17:02:32 PST 2016


Steve,


    It is persistent, it changes with time (short term time scale - between record images a fast as you can record them) and we've tried wiggling cables, re-seating connectors, etc.  I will take a look tomorrow and see what happens if we wiggle, bump, push on things during live mode...


--
            David Gene Morgan
        Electron Microscopy Center
             047D Simon Hall
             IU Bloomington
          812 856 1457 (office)
          812 856 3221 (3200)
      http://iubemcenter.indiana.edu
________________________________
From: Ludtke, Steven J <sludtke at bcm.edu>
Sent: Thursday, February 4, 2016 7:55 PM
To: Jaap Brink
Cc: Morgan, David Gene; 3dem at ncmir.ucsd.edu
Subject: Re: [3dem] more on the odd CCD image

I agree it was subtler in our case, but if I recall when we decided it might be the cable and wiggled it, I think we did get more visible noise, and this is how we decided it was actually the problem(?)   (This was maaany years ago, David)    Anyway, if it may be the cable, then wiggling it while in a faster live mode may reveal something.  I'm sure Gatan will be able to say more if the problem is persistent not transitory. I think I must have missed the original message, so I don't know what you said originally.

----------------------------------------------------------------------------
Steven Ludtke, Ph.D.
Professor, Dept. of Biochemistry and Mol. Biol.                Those who do
Co-Director National Center For Macromolecular Imaging            ARE
Baylor College of Medicine                                     The converse
sludtke at bcm.edu<mailto:sludtke at bcm.edu>  -or-  stevel at alumni.caltech.edu<mailto:stevel at alumni.caltech.edu>               also applies
http://ncmi.bcm.edu/~stevel

On Feb 4, 2016, at 6:40 PM, Jaap Brink <jbrink at jeol.com<mailto:jbrink at jeol.com>> wrote:

Steve, if I recall that event correctly weren't there a lot of spikes in the FFT? I don't remember whether or not the real space image looked this obviously bad.

Jaap
----
Jacob Brink Ph.D.
TEM Product Manager Life Sciences
JEOL USA, Inc., Peabody MA 01960
(978) 317-9561

Sent from mobile device. Please excuse typos and this reply's brevity as I'm using all thumbs to type :-)

On Feb 4, 2016, at 7:27 PM, Ludtke, Steven J <sludtke at bcm.edu<mailto:sludtke at bcm.edu>> wrote:

Electrical noise due to a loose/bad cable?  I seem to recall a case where we had a bad cable connection due to being periodically "bumped" or somesuch. This is a bit more extreme than I recall seeing, but certainly if there is a grounding issue or a bad cable all sorts of electrical badness can occur. If you know the readout rate of the detector you can estimate the frequency of the noise you're seeing.

Of course it could be something else   :^)


----------------------------------------------------------------------------
Steven Ludtke, Ph.D.
Professor, Dept. of Biochemistry and Mol. Biol.                Those who do
Co-Director National Center For Macromolecular Imaging               ARE
Baylor College of Medicine                                     The converse
sludtke at bcm.edu<mailto:sludtke at bcm.edu>  -or-  stevel at alumni.caltech.edu<mailto:stevel at alumni.caltech.edu>               also applies
http://ncmi.bcm.edu/~stevel

On Feb 4, 2016, at 6:08 PM, David Gene Morgan <dagmorga at indiana.edu<mailto:dagmorga at indiana.edu>> wrote:

Hi,

   Someone pointed out that the image I attached to my original post was not passed by the mail server.  You can see that image at:

   http://iubemcenter.indiana.edu/oddImageFromUltrascan890.html

--
               David Gene Morgan
           Electron Microscopy Center
                047D Simon Hall
                IU Bloomington
             812 856 1457 (office)
             812 856 3221 (3200)
         http://iubemcenter.indiana.edu<http://iubemcenter.indiana.edu/>
_______________________________________________
3dem mailing list
3dem at ncmir.ucsd.edu<mailto:3dem at ncmir.ucsd.edu>
https://mail.ncmir.ucsd.edu/mailman/listinfo/3dem

_______________________________________________
3dem mailing list
3dem at ncmir.ucsd.edu<mailto:3dem at ncmir.ucsd.edu>
https://mail.ncmir.ucsd.edu/mailman/listinfo/3dem

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.ncmir.ucsd.edu/pipermail/3dem/attachments/20160205/b3c285ec/attachment.html>


More information about the 3dem mailing list