LtE in CMO #247
From
António José
CIDADÃO
@. .
. . . . Finally..., here are a few Mars images (9
June, 16 June, 17 June, 28
June, 4 July, 6 July -Ed).
Right: ACd's images on 9 June 2001
25cm SCT/ST-5C
Unfortunately, I'm afraid that my contribution this
apparition will not be what I had planned :-(I have been very very busy with
work these last few months, and if you add the current positioning of Mars at
Lisbon latitude, and the unfavorable summer seeing conditions, you can
anticipate what I mean.
Mars is behind one of my
"beloved" chimneys at culmination, and before that it is hidden by
the roof. Even when it reappears, most of the time I can only use part of the
telescope's aperture, also due to the roof.
Unfortunately, it is not only light that
is lost... It is nearly impossible to produce the correct flat-field images,
because the Mars raw images often contain "partial dust doughnuts". I
had noticed this earlier in the first May images. Please keep this in mind when
analyzing the images, OK. As Maurizio had already mentioned, the IR filter is
very valuable under these unfavorable conditions. On some occasions, the UV
filter produces better (contrast) images than the B filter, although 30s
integrations are needed.
In short..., it was only yesterday that I
could work on the few images obtained during June and the first days of July.
They are not yet in my page, and I haven't send them to Marswatch either.
By the way, I had some blocking incoming
e-mail messages during late June (around last week of June I guess) and I had
no option but to delete all the mail at the server. If any of you send me some
data during that period can you send it again, please.
Regards, and good observations to all!
(
António José CIDADÃO (