At 14:11 28/08/2000 -0400, you wrote:
>We are contemplating a Zeiss LSM510 and are trying to think through the
>laser configuration.  They can only demo Option 1.
>
>Option 1: Argon, Green HeNe, Red HeNe (457, 488, 512, 543, 633)
>Option 2: Argon/Krypton, Red HeNe (or Red Diode) (488, 568, 633)
>Option 3: Argon, Nd:YAG, Red HeNe (or Red Diode) (488, 532, 633)
>
>Is a 1mW Green HeNe of any use in "typical" sample scenarios ie; not bright
>actin or tonnes of GFP?  Is the 568 line of an Argon Krypton more useful
>(power vs wavelength)?  What about a diode pumped Nd:YAG 20mW @ 532nm?

Derek,

I couldn't agree more with Aryeh's comments. We have a 0.5mW green HeNe (on
a Biorad argon ion UV system) where the power at the specimen is in the
order of 0.15mW. This is sufficient for all but the weakest specimens.
Occassionally, we could use the extra power offered by a 1.5mW laser, but
this is not that common. The HeNe lasers have been remarkably stable and
have given no trouble in 5 years of continuous use. The lifetime figures I
have been given are 7000hours for the green HeNe and 10000 hours for the
red HeNe but I can not comment on the yellow HeNe (which would likely be
good for exciting Texas Red dyes). These lifetimes compare very favourably
against the Argon/Krypton expected lifetime of about 1500 hours.

Just one comment about using multiple lasers on any confocal system - make
sure that the lasers can be well co-aligned (absolutely critical for
co-localisation studies) and that they STAY co-aligned. Obviously, the more
lasers in a system, the more difficult it is to obtain acceptable
co-alignment.

I hope this helps a little.

Regards
Paul Rigby


Dr Paul Rigby
Biomedical Confocal Microscopy Research Centre
Department of Pharmacology
The University of Western Australia
Nedlands  WA  6907
Australia
Phone: 61-8-9346 2819   Fax: 61-8-9346 3469