(IAAC) Object: M13 - Instrument: 7x50 binos

Observer: Lew Gramer
Your skills: Intermediate
Date and UT of Observation: 1997-2-9/10, 08:00 UT
Location: Medford, MA, USA (42N)
Site classification: urban
Limiting magnitude: 5.0 (zenith) 4.6 (near object)
Seeing: 3 - medium
Moon up: no
Instrument: 50mm binos
Magnification: 7x
Filters used: None
Object: M13
Category: Globular cluster
Constellation: Her
Data: mag 5.9  size 17'
RA/Dec: 16h42m   36o28'
Quickly found from memory in the same binocular field with
Eta Her (Nmost star of the keystone), M13 stands out as a
bright, non-stellar smudge in 7x50s, even under these awful
conditions. On this night, decent seeing allowed some detail
to be seen in the Great Hercules Cluster: the blotch of haze
grew gradually much brighter toward the middle, with a hint
of a tight core in still moments. The apparent size was a tad
over 10' of arc, and comparison with nearby stars (using the
"out-of-focus" trick) put M13 at about mag 5.5. Seeing was NOT
good enough however (or perhaps the sky was not dark enough)
to reveal the hint of irregularity which can sometimes be seen
in this bright little fuzzball, even at 7x.