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Re: (meteorobs)Dew prevention on lens with soap
>
> Ed>>Fast meteors such as the Perseids have strong emissions at the blue
>end
>of the spectrum, ie. H & K lines of Ca+. UV filters may prevent you from
>recording this region and thus reduce your chances of recording the fainter
>meteors of this type.<<
>
>For a long while I use to shoot meteors with a UV filter...got plenty of
them
>with it on. Later took it off and still get about the same magnitude
threshold
>when everything else is taken into consideration. There appears to me to be
no
>appreciable noticeable effect having a UV filter on or not when
photographing
>a meteor? I understand that the glass that makes up the lens of a camera
will
>filter out a certain amount of UV light as well? a little more filtering
>probably wouldn't hurt?
>
George:
I didn't check the transmission characteristics of a UV filter. I
suspect one would have some effect, but this may be minimal. It must have
some effect however, or why would you use one on a camera. Normal lenses
do indeed have limited uv transmission. You probably won't record much
below 360 nm.
UV spectra have been secured but these cameras had special optics, quartz
elements I believe.
Ed
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