At the end of October this comet
went into a outburst mode and became 1 million times brighter than
it was before as well as physically larger than the sun.
Here is a plot from the "comet-ml" mailing list of the change in brightness.
The comet on Oct. 25th:
This is a different scale than the image below.
This is Holmes next to the star Mirfak on Nov. 16th 2007
Very simple 15 minute shot through
80mm Stellarvue guided on a C-14 from Prospect Sandpits a
couple of miles east of Ft. Collins.