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Re: (IAAC) Lovely M56 [CCD images]



I enjoyed your images, Steve! One common problem that visual observers face is
having access to images which will even vaguely match what they are likely to
see. (Note that I didn't say "images which will show ONLY what they are likely
to see"! The truth is that most published and online astroimages actually fail
to show much detail which can be visible through an eyepiece! This is just one
reason why I enjoy taking detailed visual observing logs... ;>)
Your images of M56, M3 and NGC4656 among others, seem to delicately balance
depth of exposure over the whole area of each object, to account for a wide
dynamic range of brightness which is inherent in most deep sky objects. Thus
they give intriguing clues to observers of what to look for with their eyes!
In this way, your images are similar to some of the perfectly UNDERexposed
photographs published by Dr. Jack Newton in his earlier works.
As an exmple of this, visual observer Todd Gross notes a "snake of stars"
looping across and out of the core of M56, in an 18" reflector:
    http://www.visualdeepsky.org/logs/msg01359.html
Todd doesn't note the direction of this star snake. (Nor do you indicate
the orientation of your images, something you might like to include with
your fine, extensive comments for each image.) So it's tough to tell for
sure whether your image captures this feature or not. But there is quite
good-seeming candidate chain of stars in your image for this feature!
Wes Stone further notes in a log with an 11" SCT, that the "Most condensed
portion of the cluster seems to be elongated N-S and displaced to the SE":
    http://www.visualdeepsky.org/logs/msg00073.html
An impression of this feature also can be drawn from your image of M56!
Finally, my friend Steve Clougherty and I noted (with his 17.5" Obsession)
a most intriguing feature in this cluster just last Spring: a "dust-lane"
cutting from NE toward the center of this (obviously dust-free) object!
    http://www.visualdeepsky.org/logs/msg02301.html
Although this feature is difficult to discern (and impossible to confirm,
without image orientation information), it also seems to be shown on your
fine image of M56 - cutting diagonally across the lower 1/3 of the core.
Thanks again for sharing your images with us on the Web, Steve!
Clear skies,
Lew Gramer
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