Re. Guenter Giese's reply to Pam Reid's query:

.............
>Combination of Ar ( 457, 476, 488, 514 nm) with two HeNe lasers (543 nm,
>633  nm) is also feasible. The gap between the latter two lines may partly
>be overcome by the 594 nm HeNe laser (seems good for Texas red excitation,
>but I do not have any experience with this laser). The still remaining gap
>in the 560 to 580 nm range (for dsRed, TRITC etc.) is, in my experiences, a
>severe drawback of this combination.
>
>An interesting combination could be: Ar plus ArKr plus 594 nm HeNe (if
>Texas red is important) plus the appropriate merge module and AOTF for
>merging/selecting/adjusting the individual lines. This combination (457,
>476, 488, 514, 568, 594, 643 nm) should be appropriate for both standard
>immunofluorescence imaging and fluorescent protein life cell imaging.
..............

No manufacturer, as far as I am aware, is using the 594 laser in their
confocal.  When making a recent purchase of a confocal system, I asked to
have this laser instead of or as well as the 633 laser, but since,
apparently, none of these have been tested for stability, power, etc, this
wasn't done.  The confocal software would need to be changed, and the
correct couplings to hook the laser into the confocal would need to be
custom made and tested, etc, etc.  I hope other users/potential users
request more options in laser choice, then the manufacturers will be
prompted to test them and offer them as standard.  With the brilliant Alexa
594 dyes, and other probes absorbing in this region, it would be a real
plus to be able to use the 594 laser in particular.

cheers,
Rosemary


Rosemary White
Microscopy Centre
CSIRO Plant Industry
GPO Box 1600
Canberra, ACT 2601
Australia

phone  61-2-6246 5475
fax       61-2-6246 5000
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