Martin Kohler wrote:
 
  Solution of "temperature problem" also?
 
>When using immersion lenses in studies of living cells, one apparently
>need to heat the objective if the cell should sense 37C. One problem is
>then that the refractive index of the immersion oil is temperature
>dependent. Therefore it whould be nice to have different oils for
>different temperatures.
  >Maybe the oils from "Cargille's Laser Liquid, Series 5610" will do, or
>do you have other options out there for different temperature corrected oils?
 
Our in vivo work has been with Drosophila, which are happy at room
temperature.  However, Cargille supplies a d(nD)/dT for each oil, so you
could calculate the refractive index of the oil.  In general, we
use the nD[25] supplied by Cargille as a refernce, since it is only
valid for the Na D line at 25 deg C.
 
By the way, I've heard that it is wise to avoid cycling the temperature
on your high NA lenses.  A couple of cycles from room temperature to 37
deg C generates enough strain to dramatically change the point spread
function.  I've heard that D. L. Taylor's Lab keeps their 37 deg lenses
in a 37 deg incubator.  Is there anybody out there who can confirm
this??
 
Jason Swedlow