Re: DIC condensers

Posted by Guy Cox-2 on
URL: http://confocal-microscopy-list.275.s1.nabble.com/DIC-condensers-tp7583008p7583009.html

Jeff,

        If you want to get decent contrast in DIC you need a high NA condenser with a high NA objective.  Of course the plate must be correct for the objective, and Köhler illumination must be correctly set up.  My guess is that that wasn't true for your LED source, and you weren't filling the BFP.  Don't take this personally but the widespread use of fluorescence has made many microscopists become slack about setting up Köhler illumination!  

                                Guy

Guy Cox, Honorary Associate Professor
School of Medical Sciences

Australian Centre for Microscopy and Microanalysis,
Madsen, F09, University of Sydney, NSW 2006

-----Original Message-----
From: Confocal Microscopy List [mailto:[hidden email]] On Behalf Of Jeff Spector
Sent: Saturday, 29 November 2014 1:22 PM
To: [hidden email]
Subject: DIC condensers

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Greetings,
   This isn't exactly a "confocal" questions but I know a lot of "micoscopy gurus" live on this list so I thought it a good place to ask this. I have a colleague who is trying to image individual (i.e. small and diffraction
limited) microtubules in a flow chamber by using DIC. They are currently using a 100x 1.45 oil Objective, but only a .52 LWD condenser. They were using a solid state light source but couldn't get good image so we switched to a lamp for illumination and the images are much better, and we can now see the microtbules but there still isn't a lot of contrast.  My question is, is it worth it to go to a high NA (perhaps oil immersion) condenser, and can anyone think of why the lamp would give a better DIC image than a solid state light source?
thanks in advance for the help...
 -Jeff