I can see the advantage of this for each line being closer in time, but
does it take significantly longer to do the entire field?  If you had a
cell at high mag, how different in time is the beginning of the scan (top
of cell) to the end of scan (bottom of cell). Dave

>Yes, "multitracking" is switching between different excitations and
>emissions (split to different PMTs) on a scanline basis.  You could for
>instance have three probes-- scan one on the forward scanline, probe two on
>the flyback, probe three on a redo of the same scanline, and blanked out on
>the flyback, then on to the next line.  The real advantage to this is
>"simultaneous" scanning without crosstalk, very important for colocalization
>studies.  You do lose a little sensitivity since you are splitting the
>emission, rather than using a single PMT as we normally do with frame by
>frame sequential scans.
>
>Jeff
>
>> ----------
>> From:         Ray Hicks
>> Reply To:     Confocal Microscopy List
>> Sent:         Wednesday, December 8, 1999 10:48 AM
>> To:   [log in to unmask]
>> Subject:      Re: COMPARISON OF CONFOCAL SYSTEMS
>>
>> The Leica TCS-SP that I use has excellent spectral characteristics, and
>> can
>> scan sequentially (ie scan successive images using different excitation
>> lines, and assemble them as an overlay), so I don't see that the problem
>> with crosstalk rejection on the SP, mentioned earlier in this thread, is
>> real.
>>
>> I was about to ask what multitracking was when Bob stepped in, I presume
>> that it is the sequential use of different laser lines on a scan-line
>> basis
>> rather than a whole image basis, am I right?  If so then there may be
>> speed
>> improvement, but not necessarily a quality improvement.  Both methods
>> would
>> appear to provide temporal separation, but with a different magnitude of
>> delay between subsequent excitations.  Sequential image scanning would
>> seem
>> to have an advantage when attempting to separate the long-lived
>> luminescences available from the recently developed nanocrystal and
>> frequency-doubling-phosphor technologies.
>>
>> Ray
>>
>>
>>
>>  >Robert Zucker <[log in to unmask]> wrote in message news:
>> ><[log in to unmask]>...
>> >> Mike
>> >> I know about the Leica filterless SP system's importance.
>> >> What is a multitracking confocal microscope and why is this important?
>> >> Bob
>> >
>> >Two reasons come to mind.  Eliminating bleed through by sequentially
>> firing
>> >the lasers really did indicate the level of bleed and cleaned up the
>> images
>> >fantastically (at a slower scan rate, however).  Also, another benefit of
>> >improved scan control was being able to exert fine control for
>> >photobleaching studies.  We found being able to 'design' our own ROIs for
>> >bleaching (whatever shape we needed) was extremely useful.  This was
>> >particularly beneficial when wanting to bleach various regions of
>> differing
>> >size and shape.  For our work, I need to put the photobleaching control
>> high
>> >up on the want list; more generically, most folks would probably
>> appreciate
>> >less bleed.  I guess we'll all see how much of this the new leica will be
>> >able to do when they start demo'ing it....
>> >
>> >Michael A. Mancini, Ph.D.
>> >Department of Molecular and Cellular Biology
>> >Baylor College of Medicine
>> >Houston, TX
>> >[log in to unmask]
>>
>>
>>                               Ray Hicks
>> ________________________________________________________________________
>> |University of Cambridge          |Tel              01223 330149        |
>> |Department of Medicine           |Fax             01223 336846         |
>> |Level 5, Addenbrookes Hospital   |e-mail         <[log in to unmask]> |
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>> |CB2                              |ftp server  ftp://131.111.80.78      |
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>> |_________________________________|_____________________________________|
>>
>>



************************************************************

Dr. David Knecht
Department of Molecular and Cell Biology
University of Connecticut
75 N. Eagleville Rd.   U-125
Storrs, CT 06269
[log in to unmask]
860-486-2200      860-486-4331 (fax)
home page: http://www.sp.uconn.edu/~mcbstaff/knecht/knecht.html
************************************************************