Brightness difference Hg vs LED

[lgelman]

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Dear Claire,

Sure, for most applications, and in particular for live cell imaging, the power of current LED light sources are sufficient, and we have many of these devices on our facility.
Nevertheless, on macroscopes equipped with 0.8x to 2.5x lenses and large camera chips, the field of illumination is very wide, and we have experienced some limitations with these LED sources when looking at organs with fluorescent labels. There, the more, the better, and using a Metal Halide light source was making a big difference with some faintly labelled samples/organs.

Best regards,

Laurent.


_____________________________________________
Laurent Gelman, PhD
Head of Facility for Advanced Imaging and Microscopy
(Light Microscopy)

Friedrich Miescher Institut
WRO 1066.2.16
Maulbeerstrasse 66
CH-4058 Basel
Fix: [phone]
Mobile: [phone]
Fax: [phone]

www.fmi.ch
www.microscopynetwork.unibas.ch/



-----Original Message-----
From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Claire Brown
Sent: 06 November 2013 16:40
To: [hidden email]
Subject: Re: Brightness difference Hg vs LED

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We have been testing a number of the solid state light sources. We do a lot of live cell imaging and they are all way too bright for live cells. We either add more ND filters so the cells don't die or we turn them way down in % output if that is an option on the light source. The companies seem to be making them brighter and brighter. I would love to know what applications people have that need all this light? We usually advise people to use less light and longer exposure times even with fixed samples.

That being said we were able to get institutional support to replace our mercury sources as part of a sustainability program at McGill in a Mercury Free Microscopy initiative. This will save us lots of time and money in replacing the mercury bulbs all the time in addition to a reduction in mercury. Depending on how the sources are used they can also save a lot in power consumption too.

We have been more interested in stability of the light sources on different time scales and they really perform well. Variability is in the single percentage range or less on most time scales. I would be happy to provide more information to anyone offline if they want to contact me.

Sincerely,

Claire