More power and less exposure or vice versa – use of 100% laser

Posted by Seb Stephens on
URL: http://confocal-microscopy-list.275.s1.nabble.com/More-power-and-less-exposure-or-vice-versa-use-of-100-laser-tp3246685.html

Hi,

100% laser for 1 ms OR 1% laser for 100ms?

This is a subject that has been bothering me and I have never got quite the
answer for it.

After speaking to someone who uses 100% laser power (sorry I don’t know
what the actual laser output is) I noted their goal was to expose for the least
amount of time possible (which was only a few millesecs). This enticed me to
check myself how my protein structures (podosomes) could handle 100% laser
power as opposed to 30% which I usually use. As expected the exposure
times went down significantly (from 320 ms to 30ms) and in fact I was able to
still get decent information from 10ms exposures taken every sec for 3 mins.
Surprisingly, I saw no detectable bleach and it did not seem any different to
long exposure times with less laser power.

Im only new to microscopy and surely others must have experimented with:
high laser+ low exp compared to low laser+high exp.

I really want to know, which one should I do (high or low power)?

It seems that there could be mathematically and practically equivalents of
high laser+low exp to low laser+high exp (ie as above 100ms 1% power pairs
with 1ms 100% laser power). So, is there a relationship between power and
exposure time exists that can sort of be mathematically related?

Cheers

Seb