A CCD-based system designed to do what Aryeh proposes ("... to image
action potentials (using potential sensitive dyes) in real time.") is
commercially available.  For information about it, go to
www.redshirtimaging.com
or contact me.



Alan Fine
Professor
Department of Physiology and Biophysics
Dalhousie University Faculty of Medicine
Halifax, Nova Scotia B3H 4H7 Canada
  tel: +1-902-494-1251
  fax: +1-902-494-1685
  e-mail:  [log in to unmask]



On Wed, 28 Feb 2001, Aryeh Weiss wrote:

> I get the impression that there is a bit of confusion regarding digital
> cameras. The term has been used to refer to cameras that are based on
> various popular still cameras (like the Nikon Coolpix) and also to refer
> to high end scientific imagers. For people interested in rapid framing
> at high resolution, the former are out of the question. The latter are
> available in various models that provide 12 frames/sec, and more if you
> use binning (lowering the spatial resolution but ehancing sensitivity).
>
> I have had nice images with the DVC 1310 run at 12 frames/sec at high
> gain. You can do the same for almost any camera based on the Sony IX085
> CCD.
> PCO makes one called the PixelFly that does the same. You can get them
> for color  or monochrome. All this does not require an intensifier. If
> you can see it by eye then you can probably see it with the camera at
> high gain.
>
> If you have really weak signals and you need to see them at video rates,
> then you can use an intensifier. But I wonder if the new Marconi chip
> will take up some of that market and replace many intensified systems.
>
> Then there are fast framing system that can operate at 100s or even
> 1000s of  frames per sec. Frame sizes here run from about 256x256 and
> down. They are expensive, but they can be purchased and will do thing
> like motion analysis and such. With an intensifier I bet that they can
> be used to image action potentials (using potential sensitive dyes) in
> real time.
>
> These systems can be found  by web search, or by looking at magazines
> like Advanced Imaging or Photonics Spectra and such, which can be gotten
> for free (or seen on the web).
>
> --aryeh
> --
> Aryeh Weiss                          | email: [log in to unmask]
> Department of Electronics            | URL:
> http://optics.jct.ac.il/~aryeh
> Jerusalem College of Technology      | phone: 972-2-6751146
> POB 16031                            | FAX:   972-2-6751275
> Jerusalem, Israel                    | ham radio: 4X1PB/KA1PB
>