LtE in CMO #247,248,249
From Maurice VALIMBERTI
@. . . . . . Thank you for including some of my
images on your excellent CMO website. I recently received a forwarded message
from Barry Adcock in which you have asked about some of my details. I am happy to
provide them.
I observe from Viewbank, a suburb of
My location is very close to Barry Adcocks
home, the co-ordinates are approximately S 37d 44m 2s lat. and 145d 5m 45s
long. Altitude about 47 metres.
I
currently use a 15cm f/11 refractor with a TeleVue 5x
'Powermate' at my home observatory for my imaging purposes, together with a
'cookbook' style TC245 based CCD camera. Generally I take filtered images
through a BVRI set made for me by Steve Lee from the Anglo Australian
Observatory. For processing I use the Berry/Burnell unsharp masking and Van
Cittert deconvolution routines in AIP4WIN, together with final touch-ups in
Photoshop.
I have attached a four image set from the 4th July;
covering the time period from 9:14 UT
to 12:4 5UT, and
showing the dust cloud movement over the
p limb.
Also,
I have attached a more recent version of my image from the 26th June -I believe the
one you have on your web page is the initial draft which contained some errors
- I had very little sleep over that two day period.
For
now, I wait for the sky to clear, in the hope of imaging again soon.
(
@ . . . . . . . . . . . Thank you for your reply. I
would be glad to send you my images as they come to hand. Yes, Mars is
currently very close to the zenith, and so is very favourable for observations
from here - the only thing against me at the moment is the weather! Who shall I
send my images to? Is your e-mail address OK?
(
@. . . . . . Thank you for including my images of
the 13th July on your
CMO website.
Barry
Adcock has asked that I forward my
images to you through him - he is the solar system section Director of the
Astronomical society of
Recently,
I have read with interest your CMO#10 Director's report. You make mention of a
number of image processing methods, and to some degree make comment on their
relative merits. I thought that I would seek your guidance in this matter.
I
personally have approached the processing of my Mars image data with the
following strategy in mind:
I
feel that because of the enormous flexibility that CCD imaging can provide, we are
not bound by what merely appears visually through the eyepiece those subtle
colour differences that we cannot pick up visually can be accentuated by
appropriate image processing, which can, in turn, lead us to a better
understanding of the dynamics of the weather patterns which we are witnessing.
This is what I have attempted to do in my images.
I
do not favour LRGB processing, nor do I favour synthesized layer processing.
Since June, I have produced purely RVB (as RGB) images - all IR blocked.
What
I have done though, is to accentuate certain colour components so as to enhance
the perception of the data present. Should I also include an image balanced in
such a way as to mimic what I see visually in my telescope with my composites?
As an example, please see the attached image from the 9th July. The image on
the left is balanced to
simulate my eyepiece view.
The image on
the right has been processed by harder unsharp masking and by biasing the gamma
scaling of the BV & R channels to enhance the differences between image
components. Note that the processing of the individual raw image channel data
for both is exactly the same. It is in the assembly of the colour composite
where there is a difference.
Dust is
obvious in both images; but the one on the right I think shows more clearly a
variation in intensity of the dust distribution. See particularly the more
prominent line extending from around Thaumasia to Aonius Sinus. M. Erythraeum
is more obvious in the rightmost image, but is relatively undefined. There
appears to be a more intense dust area running S to N through it.
In your opinion, should I alter my strategy?
Am I approaching the task inappropriately?
Are you aware of the strategies employed by other imagers; and are mine
similar to those?
I look forward to your comments.
Kind
regards
(
@ . . . . . . . I looked at your CMO web page today
and noticed that my image from the 24th does not appear. I
am wondering if you have received the attached information which I sent to
Barry Adcock? Subtle, yet interesting
dust patterns show. Regards
(
Maurice VALIMBERTI (