Re: Finding the 458nm laser line of a Coherent innova Spectrum Laser70 on FACSVantageSE

Alex Schmitz wrote-

>I ran into trouble finding the 458nm laser line of our Innova Spectrum70 
>Laser on our FACSVantage SE for ECFP analysis.
>Actually I can tune to 6 lines below the very strong 488nm line. (UV is 
>probably not visible)
>
>The Innova handbook says:
>70C-Spectrum:
>488.0: 0.25Watt;
>476.5: 0.10
>472.2: ----
>465.8: ----
>457.9: 0.03
>Multiline UV: 0.05
>So which one is the 458 ?. The first visible one ?
>
>Unfortunately I currently have no strong ECFP expressing cell line for 
>fishing in the dark.
>Are there any beads that are somewhat specific for that laserline ?
>I tried Sphero-Yellow bright with not much success...
>I am running the laser as  secondary laser (488 primary, outsplitted UV as 
>laser3).
>I used a 649LP filter and collected the reflected light with a special 
>473/19 filter (as discussed previously in that group).

The 458 (457.9) nm line is a relatively low-gain line, and, unless your 
plasma tube is pretty perky and your mirrors are clean and well aligned, 
you might not see it at all.

An argon laser emits strong lines at 514.5 and 488 nm, and weaker lines at 
501.7, 496.5, 476.5, 472.7, 465.8, 457.9, and 454.5 nm. If you can see six 
lines below 488 nm, it's because the Spectrum is a mixed argon-krypton 
laser, and you are probably picking up weak emission on the 482.5, 476.2, 
and/or 468.0 nm krypton lines, because there aren't six visible lines below 
488 in an argon laser. The 454.5 nm argon line is even weaker than the 
457.9, so it's a safe bet that the 457.9 nm line will be the deepest blue 
one you can see; you shouldn't be able to get UV from the visible mirrors. 
Of course, you should be wearing your laser safety glasses, so you won't be 
able to see any of the lines...


-Howard