January 24th 04, 04:09 AM
"astroguy" > wrote in message >...
> "Jack Schmidling" > wrote in message
> news:[email protected]
> > "Dennis Persyk"
> > > Images at
> > > http://home.att.net/~dpersyk/new.htm
> > >
> > > The comet is slowly brightening and the tail is lengthening
> > > perceptibly each night. This is a very dynamic imaging target now!
> > Welcome to the group Dennis. In case I did not make myself clear, you are
> > permitted to post images directly (attach) in this ng. That doesn't help
> > much when you have a page full of stuff but just wanted to make sure you
> > know.
> well, in fact it is not allowed to post images in this group, use
> alt.binaries.pictures.astro for that.
> > Nice comet pics but I do not understand the difference between the two
> > images. One has pin point stars and the other has long trails with an
> > accent at one end and the time exposure time difference does not seem to
> > explain things.
> the difference is that one photo is guided, the other not. AFAIK
The comet is moving with respect to the stars. When I stack several
images to improve the signal to noise ratio, I can either align on the
stars and get a blurry comet or align on the comet head and get
trailed stars. I like to show both kinds of stacked images.