No, no, it IS the problem!  As Mike Ignatius explained, MP put the beads on the slide, not the coverslip, then add mountant and then the coverslip.  If you are using a #1.5 coverslip you need to put the beads directly on the coverslip.  With the beads on the slide the extra thickness of the mountant needs to be corrected for by using a thinner coverslip - #1 or #0 - which must be found by trial and error.  (But since I guess they are using very reproducible conditions they only need to do the test once).  At least it seems they have realized they have a problem.  

                                       Guy

-----Original Message-----
From: Confocal Microscopy List [mailto:[log in to unmask]] On Behalf Of MICROSCOPIA CONFOCAL y CCD
Sent: Thursday, 25 March 2010 10:15 PM
To: [log in to unmask]
Subject: Re: FocalCheck test slide

>Thanks a lot for your answers.

>Of course I put the slide upside down when using 
>inverted microscope and I asked for Molecular 
>probes about coverslip and they answered me: 
>"The coverslip thickness for the FocalCheck 
>prepared slides is 0.13-0.16 mm" It´s no ideal 
>but I think that this is not the problem.

M. Teresa

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