Peter,

Thanks for making the effort to obtain photometry of this fascinating
comet. This is particularly important at the moment since most of the
robotic telescopes further south than us can't get on it since it is too
low for them. We have a big advantage at our northern latitudes!

For the interest of others who might be encouraged to take part in this
project, the details of how we are doing this are set out below. Having
a consistent approach means that we can get a nice lightcurve showing
the outbursts. The latest version of this is here:

https://nickdjames.com/Comets/2024/12P_lightcurve_9arcsec.png

The photometry is done using unfiltered images with Astrometrica set to
use Gaia DR2 as the reference catalogue. Set the colour band to "Gaia
Broadband (G)" and the filter to "Clear/None". On the "Program" tab
select an aperture radius which corresponds as close as possible to 9
arcsec given your pixel scale. For observations to be included in the
dataset you need to send me the photometry file (called PhotReport.txt).
You can also send me the astrometry file (called ADESReport.PSV in
recent versions of Astrometrica) but this isn't used for the lightcurve.
Please send the files to my email address and remember to send them as
attachments so that they don't get mangled by email software.

Many thanks to everyone who has submitted observations so far. We have a
really nice dataset. An updated report on this comet will appear in the
February JBAA.

Nick.

On 27/01/2024 18:12, denis buczynski - buczynski8166 at btinternet.com
(via baa-comet list) wrote:
> I expect Nick will ask you to remeasure them using Gaia catalogue rather
> than UCAC4. You can choose that catalogue in the drop down list in
> Astrometrica, also choose Gaia Broadband (G) and your filter to clear.
> Denis