[vsnet-chat 1301] [vsnet-obs 14762] Re: V3885 Sgr, thisseason

[Berto Monard <lagmonar@csir.co.za>]

Hi, 

I would like to respond, although late, to this interesting analysis
from Dr Kato who stated: 

>>> Taichi Kato <tkato@kusastro.kyoto-u.ac.jp> 09/08 4:26 AM >>>
Re: [vsnet-obs 14762] Re: V3885 Sgr, this season


 I have confirmed T. Watanabe also used H/T.  So this systematic
difference may be attributed to personal perception to the blue light.
 Two possible reasons:

   1. Japanese sky is polluted enough to discourage CV observers (;_;)

      (However, T. Watanabe usually observes from Mt. Fuji, the
highest
       mountain in Japan, but slightly lower than Mauna Kea, this
effect
       might be then avoided, or the air pollution already prevailing
all
       heights of atmosphere?)

   2. Dark adaptation, but I presume he is reasonably dark adapted in
the
      dark environment of the mountain.

   Considering the typical color of B-V=0 for these bright novalikes,
there
will not be a large difference in color term by the effect (2). 
However,
the situation will be different if Monard's eye has a sensitivity to
the U
light!  CVs are bluer than OB stars in the U-B index.

   How do you think?

Regards,
Taichi Kato

////
I wonder how serious Taichi was in:
'However, the situation will be different if Monard's eye has a
sensitivity to the U light!  CVs are bluer than OB stars in the U-B
index.'

It of course depends which eye is refered to, they differ...but I do
believe in the possibility of human vision in the UV. 
The 'average' human visual responsivity (refered to that of 'the
standard observer') was determined some time ago (CIE 1931). It is not
clear how accurate those values are, specifically those at the end
wavelengths, in particular the shorter wavelengths (with inclusion of
the ultraviolet). 
Some years ago I 'tested' this UV vision together with a former
colleague, now happily retired and playing golf on the Cape Coast. We
found that we noticed certain 'violetish' light originating from a
UV-A source (medium pressure Hg lamp) which was fitted with an extra
UV-A filter for additional blockage. 
I plan to do this test over again, just as a matter of curiosity,
after the move of the UV laboratory (a move due to works). 

Regards,

Berto
PS and a possible answer to 'How do you think?' is: 
by means of a dynamic neural flow with stages of temporary storage,
some turbulence and lots of chaos (at least in my brain)...

joking..

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