Re: Coverslip thickness and correction collar ... option Ib

Posted by S. Pagakis (IIBEAA) on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Coverslip-thickness-and-correction-collar-tp591122p591125.html

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>
> From: Confocal Microscopy List [mailto:[hidden email]]
> On Behalf Of George McNamara
> Sent: Sunday, 9 December 2007 6:08 AM
> To: [hidden email]
> Subject: Re: Coverslip thickness and correction collar ... option Ib
>
> Search the CONFOCAL archive at
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>
> option Ib. Measure of the glass thickness before you culture your
> cells. Then, for this lens, use dishes whose coverglasses are 170 um
> (or whatever thickness works best for the lens at its current
> "optimal" setting).
>
> If one in five are the right thickness, than the cost of that dish,
> for this experiment, has gone from about $2 to $10. Should take less
> than a minute to measure a dish using a 20x, decent NA, dry lens.


Dear George

On a recent test I did, I discovered something that I had not expected.
A dry objective would significantly underestimate the thickness of a
glass coverslip.

For a #1 coverslip, a 20x dry objective would measure it as 98microns
thick, where as a 63oil objective as 138microns thick.
For a #1.5 coverslip the values were 113microns and 160microns
respectively.

As I said, I wasn't expecting it because the 20 lens was coverslip
corrected.

So you have to be very careful when using dry objectives to measure
anything in Z.

regards

*********************************
Stamatis Pagakis Ph.D.
Biological Imaging Unit
Biomedical Research Foundation, Academy of Athens
[hidden email]




> Compared to the cost of the confocal time (or of an LSM510), or of
> your time to do manual image analysis, or cost of the analysis
> computer and image analysis software, the extra cost is trivial. Plus,
> you can sort the "rejects" and use them with lenses each thickness is
> optimized for.

> George McNamara, Ph.D.
> University of Miami, Miller School of Medicine
> Image Core
> Miami, FL 33010
> [hidden email]
> [hidden email]
> 305-243-8436 office
> http://home.earthlink.net/~pubspectra/
> http://home.earthlink.net/~geomcnamara/
> http://www.sylvester.org/health_pro/shared_resources/index.asp (see
> Analytical Imaging Core Facility)
>
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