Re: not a confocal question - features of a widefield
Posted by
Engstrom, Lars on
URL: http://confocal-microscopy-list.275.s1.nabble.com/not-a-confocal-question-features-of-a-widefield-tp591195p591214.html
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Nikon has a Perfect Focus System I believe for their TE2000
series. It uses an LED (770nm) to focus on the coverslip and adjust Z prior to
image acquisition.
I haven't tried it but sounds similar to what you are
looking for and could use their system as an example for building your
own.
-Lars
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I've been thinking about building a system like that ever since one of our
users started doing overnight recordings and his samples sometimes drift
vertically and thus would need an autofocus system to correct for that. If
you could tap into the Z-controller circuit of your system, you would be able to
drive that with a signal that's proportional to the vertical drift. The
drift could be scaled with e.g. calculating average intensity during a
Z-stack from a certain area of the image that's fairly thin. Similar logic
would work for the autoexposure as well. Want to try it?
Zoltan
On Dec 7, 2007 4:41 PM, Nuno Moreno <
[hidden email]>
wrote:
Autoexpose
will bleach everything, right?
Regarding the adaptative focus that I
mentioned before, there are
commercial system that with minimum light and
before an acquisition
"measure" the cell position and adapt the focus. But
this is an half
adaptation. It could be that it does not need to readjust
the focus.
What I was counting with would be after the acquisition, if
it is out of
focus, it make the adjustment base in some kind of
sensitivity
parameter. This could be after 10 time points but it might be
that it
would never need such adjustment.
About the intensity
variations I'm not talking about post processing
adjustments. If it gets
saturated there are no post processing that can
help
you.
Regards,
NM
Shalin Mehta wrote:
> Search the
CONFOCAL archive at
>
http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal Dear
Nuno,
>
> Wouldn't auto-exposure on cameras suffice for
maintaining constant
> intensity?
>
> Apparently most of the
commercial adaptive optics systems are geared
> towards astronomy.
Perhaps you have known this already:
>
http://cfao.ucolick.org/> Interesting to note that
James Webb space telescope will have hardware
> and intelligence for
adaptive optics evolved from algorithms developed
> for correcting
aberrations for hubble telescope.
>
> Regards,
>
Shalin
>
>
> On Dec 7, 2007 10:43 PM, Nuno Moreno <
[hidden email]> <mailto:
[hidden email]>>
wrote:
>
> Search the CONFOCAL archive at
>
http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal>
>
Does anyone knows any commercial widefield SYSTEM that makes
an
> adaptative focus. And I mean adaptative (follows the
cell.
>
> The other feature is a commercial system
that keeps intensities, i.e.,
> if you have something with
different protein expression levels over
> time, the
system will correct the exposure time so that at the end the
>
intensities are constant.
>
> Many
thanks,
> --
> Nuno Moreno
>
Cell Imaging Unit
> Instituto Gulbenkian de
Ciência
>
http://www.igc.gulbekian.pt
> phone +351
214464606
> fax +351
214407970
>
>
>
>
> --
>
~~~~~~~~~~~~~~~~~~~~~~~~~
> Shalin Mehta
> Graduate Student in
Bioengineering, NUS
> mobile: +65-90694182
>
~~~~~~~~~~~~~~~~~~~~~~~~~~
--
--
--
Zoltan Cseresnyes
Facility manager, Imaging Suite
Dept. of
Zoology University of Cambridge
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