| Steve Bodin | ||||
| Galaxies:
M49 / NGC 4488
Date & Time: 5 June 2003 11 PM to 1 am Seeing: 4 <1-10 Seeing Scale (10 best)>. Transparency: fair to good Location of site: Silverdale WA, USA 47N 123W Site classification: suburb-rural Conditions: temp 65 F, dry Sky darkness: 5.0 <Limiting magnitude> Telescope: 17.5 DOB, Bigdog Eyepieces: not used Additional: DX-8263SL video camera at f3 Magnification: app. 200x integrated 2 sec exposures
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M49 is sinking
fast in the
twilight, so imaged and observed with the moon still high in the sky
and
interfering with the limiting magnitude. This galaxy is extremely
yellow
on the tv monitor and very bright too. Burnham states that the
integrated
spectral type is G7, almost to the yellow-orange side of the chart.
But,
like all the faint fuzzies, it just looks grey-green in the eyepiece.
Which
brings up a question. What is the true color of a DSO? If they all look
grey-green then that is the color, because they are all too faint. If
you
get close enough to see color, the faint fuzzy is too diffuse to see
anything
at all! Ask yourself, what is the color of the Milky Way? To me,
it is a colorless faint glow, maybe whitish or greyish. Well, that is
about
as close to a galaxy as you can get and there is no color, so what are
we doing with these exercises in color on DSOs? Even the Hubble images
are " false color" since all the images are taken through an alphabet
soup
of filters on B/W CCDs for scientific purposes. Then some guy in a
closet
assigns a "color" to each of the UBVIRLMNOP filters and presto a
"color"
picture of a DSO. Enough soap box. Don't get me wrong, I like taking
color
images, but the correctness of the color balance exercises seem to be
getting
too fine for me, see this months S&T. M49 has a faint companion,
but
too far to fit in the same FOV, NGC4488 a faint and non-descript spiral.
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