Benedikt,

Another quick comment - make sure that you microscope / confocal
configuration has room to take an extra port for the video camera. We have
a Cohu video camera on an Olympus AX70 base and BioRad 1024 scanhead. We
ahd to get the scanhead support modified so make room for the camera. The
dual port set-up we have on the Ax70 is really good in that you can centre
the video port to get the video image aligned exactly with the confocal
image. Small point, but it really helps a lot!

IAN




On Fri, 30 May 1997 10:33:13 -0400, Benedikt Kost wrote:

>We are studying  weakly fluorescent structures in living pollen tubes.
>Since in pollen tubes everything is moving very rapidly with the
>cytoplasmic streaming, our Zeiss LSM 410 is only of limited use for imaging
>these structures (even at the higest scan speed images are smeared and real
>time imaging is not possible/  images are generally noisy at high scan
>speeds). In order to be able to record films of what we see, we would like
>to add a video camera to our confocal microscope. We hope that somebody
>else has been in a similar situation and can give us some advice. At the
>moment we are trying to decide between two basic options:
>
>1) we could go for an intensified ccd camera with a standard video output.
>We have the impression that a standard video output is not very handy, we
>think we would additionally need a frame grabber to digitize the data.
>Initially, we had hoped to be able to use the matrox board that is part of
>the confocal system for this purpose, but Zeiss people don't think this
>solution is practicable. One problem is that the matrox board is apparently
>too slow for "real time" image digitization. However, fast enough frame
>grabbers seem to be commercially available, although we don't have concrete
>information at this time. It is also not clear to us, to which extent the
>process of acquiring analog images and digitizing them later is
>compromizing image qualitiy (as compared to directly acquiring digital
>images).
>
>2) Princton instruments sells ccd cameras (Pentamax series) with a fully
>digital output that are apparently able to send something like 15 images
>per second (512x512 resolution, below video rate but good enough for
>something that is perceived as a film?) directly into the RAM. These
>cameras are expensive (30'000-43'000 US$ just for the camera). They come in
>two basic versions: with and without intensifier. We have had the
>non-intensified version (with a chip that can be cooled to about -30 C) in
>the lab. What we saw was quite nice, but we could not make use of the full
>camera speed because we had to use somewhat longer than minimal exposure
>times to get a reasonable signal. The options we would like to test are:
>the  non-intensified version with a back-illuminated chip (clearly higher
>QE in the visible range) and the intensified version. We believe that a
>non-intesified camera would give us more flexibility, it can also be run in
>a slow read-out, long integration mode for very weekly fluorescent, fixed
>samples.
>
>Our main question are:
>
>a) A digital system will be clearly more expensive than a system with just
>a standard video out-put. What do people think about our assumption that
>the advantages are worth the effort?
>
>b) Is the option" intesified standard video system plus frame grabber" less
>expensive that the digital Princton Instruments cameras? How much does
>image quality suffer when a standard video signal is digitized (as compared
>to directly acquiring digital images)?
>
>d) Do companies other than Princton Instrumtents sell fully digital video
>cameras with very high read-out speed?
>
>c) Can anybody recommend a reasonably priced camera system that is used for
>an application similar to ours?
>
>We greatly appreciate any comments and suggestions!
>
>Thanks!
>
>Benedikt
>
>
>
>----------------------------------------------------------------------------
>--------------------
>Dr. Benedikt Kost
>
>Lab of Plant Molecular Biology
>RU box 162
>The Rockefeller University
>1230 York Avenue
>New York, NY 10021-6399
>USA
>
>Fax    +1 212 327 8327
>Tel    +1 212 327 8045
>[log in to unmask]
Professor Ian Gibbins                         Flinders Microscopy &
Department of Anatomy and Histology            Image Analysis Facility
Flinders University of South Australia
GPO Box 2100 Adelaide 5001                    Centre for Neuroscience
AUSTRALIA
Phone:  +61-8-2045271
FAX:    +61-8-2770085
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