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<DIV>Hi Mike,</DIV>
<DIV>Welcome to the fascinating world of comet imaging. </DIV>
<DIV>Imaging comets is similar to deep sky object imaging except the target is
moving! Because comets move you’ll find an exposure longer than a minute or two
will smear out the comet. The actual longest exposure duration will of course
depend on how bright the comet is and how fast the comet is moving. What makes
comet observing fascinating is that all comets do different things including how
fast they move across the sky.</DIV>
<DIV>Your telescope at f/6 is well suited to comet imaging so I’d start off by
picking a moderately bright comet
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style='FONT-SIZE: small; TEXT-DECORATION: none; FONT-FAMILY: "Calibri"; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; DISPLAY: inline'>and
take several consecutive exposures (say 10) of about 60 to 120 seconds duration
in monochrome only. Then stack the images with the comet as the reference point.
You’ll find the resulting image shows the comet fixed against a background of
trailed stars. This is the technique most comet imagers use.</DIV></DIV>
<DIV>
<DIV
style='FONT-SIZE: small; TEXT-DECORATION: none; FONT-FAMILY: "Calibri"; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; DISPLAY: inline'>Have
a read of the BAA’s Comet section observing guide, section 5 deals with imaging.
<A title=https://www.britastro.org/node/6817
href="https://www.britastro.org/node/6817">https://www.britastro.org/node/6817</A>
When you mastered monochrome then LRGB colour imaging will be less difficult
because you’ll have an appreciation of the likely problem areas.</DIV></DIV>
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style='FONT-SIZE: small; TEXT-DECORATION: none; FONT-FAMILY: "Calibri"; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; DISPLAY: inline'>Good
luck</DIV></DIV>
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style='FONT-SIZE: small; TEXT-DECORATION: none; FONT-FAMILY: "Calibri"; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; DISPLAY: inline'>Peter
Caron</DIV></DIV>
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<DIV
style='FONT-SIZE: small; TEXT-DECORATION: none; FONT-FAMILY: "Calibri"; FONT-WEIGHT: normal; COLOR: #000000; FONT-STYLE: normal; DISPLAY: inline'><B>From:</B>
<A title=mikepaling@madasafish.com href="mailto:mikepaling@madasafish.com">Mike
Paling</A> </DIV>
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<DIV style="BACKGROUND: #f5f5f5">
<DIV><B>Sent:</B> Wednesday, May 02, 2018 5:59 PM</DIV>
<DIV><B>To:</B> <A title=comets-disc@britastro.org
href="mailto:comets-disc@britastro.org">comets-disc@britastro.org</A> </DIV>
<DIV><B>Subject:</B> [BAA Comets] Help please?</DIV></DIV></DIV>
<DIV> </DIV></DIV>
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<DIV>Hi ...</DIV>
<DIV>I am trying to get into imaging comets .... I am very much a beginner with
this aspect of astro photography.</DIV>
<DIV> </DIV>
<DIV>I have a pretty decent permanent setup here in Nottinghamshire ... my mount
is capable of up to 20 minutes unguided tracking and my CCD mono camera has LRGB
(and also Ha) filters. My scope is a 123 mm x 780 mm focal length f6
refractor.</DIV>
<DIV> </DIV>
<DIV>Can anybody suggest suitable exposure times to use with my LRGB filters?
</DIV>
<DIV> </DIV>
<DIV>Many thanks in anticipation of any help that can be given to my question
:-)</DIV>
<DIV> </DIV>
<DIV>Regards Mike</DIV>
<DIV> </DIV>
<DIV> </DIV></DIV></DIV>
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