From: sprengel@scan.genetik.uni-koeln.de (Joerg Sprengel)
Newsgroups: bionet.molbio.methds-reagnts
Subject: Summary: Phosphoimager experiences
Date: 16 Dec 92 13:39:31
Organization: Institute of Genetics/Dept. Virology, Cologne, Germany
Distribution: bionet
NNTP-Posting-Host: scan.genetik.uni-koeln.de

Dear Netters,

thanks to all of you which responded to my questions concerning
phospho imager like machines.  

Nearly all of you are (very) satisfied with these, especially
Molecular Dynamics (MD) machines. Only one person,
IBELGAUFTS@genmic.biochem.mpg.de, suggested that we should save the
money for the machine and should buy conventional X-ray films instead.

The MD plates, which are mentioned to be produced by Kodak Eastman in
License to Fuji, are 7 to 10 times more sensitive than conventional
films. Fuji sells one sensitive to 3H, which in contrast to the other
plates con be used only once. The linearity is immense. It spans about
5 orders of magnitude, so that you can quantify very faint bands,
spots, dots to overexposed regions. The exposing time can be
reduced from overnight to 1 hour +/-.  The plates will last forever: 

>  Immaging plates will last forever, if you don't abuse them (don't
>  have them in a central facility or loan them out to unknown PhD
>  students)

as jjw@rsbs0.anu.edu.au ( Jeremy Weinman) writes.

The main problem with the analyses is the printing quality which does
not seem to be sufficient for publication purposes, even on 600 dpi
lasers. To circumvent this you can attach a greyscale videoprinter
black/white or a much more expensive color thermotransfer printer. You
can buy 256 greyscale emulation cards for Laserjet printers. As an
alternative you can use a service which exists probably round the
corner. It allows you to send the graphic data (normalized, in respect
to color correction, TIFF) to a publishing company. They will expose
***very*** high quality films, transparencies, slides,...

Another drawback is, can be, the size of the raw image data, which can
grow up to 30-40 Mb per picture, so one has to invest into a tapedrive
and addidional harddiscs. The analyzing software for the MD requires
MS windows, I've got no information about the Fuji system, which runs
on a Sun workstation an Sunview windowing system. Unfortunately I got
no information about phosphoimager (is this term copyrighted by MD?)
systems which can be controlled by a Un*x workstation, like Fuji's.


Once again thanks to all of you,


HSIEH@CVLAB.HARVARD.EDU (CHUNG-MING HSIEH)             
"JONG, SONG-MUH J" <SJJ@icbr.ifas.ufl.edu>             
"Thomas_C.Newman" <22313TCN@msu.edu>                   
BMHTLAI@TWNAS886.bitnet                                
"David Stern" <David_Stern@qmrelay.mail.cornell.edu>   
greg@mendel.llnl.gov                                   
marder@agri.huji.ac.il                                 
dresnick@athena.mit.edu (David I Resnick)              
jjw@rsbs0.anu.edu.au ( Jeremy Weinman)                 
pablo@acsu.buffalo.edu (Juan P. Abonia)                
IBELGAUFTS@genmic.biochem.mpg.de                       


if one is interested, I will send a Mail digest of the responses to
you. 










--

           //							     
          Jorg  Sprengel					     
						    		     
						    		     
    Institute of Genetics                sprengel@scan.genetik.uni-koeln.de
        Dept. Virology                       aeg07@rs1.rrz.uni-koeln.de    
         Weyertal 121       	               Tel.: x49 221 470 3405       
       W5000 Cologne 41		               FAX : x49 221 470 5163       
           Germany