succession as you can carefully do. It doesn't matter that you don't
have a guiding system, because you're going to visually put the
planetary image somewhere in the frame (accuracy isn't important so
long as you capture the entire planetary disc). The accurate alignment
will be done in software.
I have tried stacking a couple of frames but the image is rather small to
pick up on a particular detail.
I current use a 9mm Super-Wide Knight Owl EP that doesn't barlow well on the
planets and a Knight Owl MC series 25mm for lunar.
The rule of thumb is the more frames the
better; Daniele Gasparri says that his recent image of Saturn was made
of 1,500 frames from a Philips webcam
http://www.marcofazzoli.com/danielegasparri/html_eng/saturn_050302.htm.
Fantastic shot!!!
Nonetheless, you can make very good images with half a dozen
still-camera frames if they are focused and exposed with care -- and
with a decent sky and a bit of practice. You should be able to capture
Saturn or Jupiter with shutter speeds slower than 1/250, but I'm a bit
too lazy to calculate the minimum speed that you need with an unguided
'scope. Patient experimentation with note-taking as to what you did
during each imaging session is the key. After a successful session you
consult your notes and do the same thing at the next session. If that
session also succeeds, you have your technique and the rest is
gathering experiencing and refinement of the technique.
I haven't been taking too many notes although I do check the EXIF of
previous successful shots as a starting point.
I have uploaded a couple of the recent pictures onto
alt.binaries.pictures.astro.
Thanks Davoud
Brian
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