Thanks very much Peter, that clarifies things a lot. I hadn’t thought that it was the center of the groups that was used to determine their distance apart on the solar disk, I had just assumed that it was how close their edges were. So that helps. I also didn’t realise it was just the umbrae that counted towards the spot number, either. I think I might try and add some observations to the database that you mentioned once I get the hang of things a bit better but I notice from your newsletter that we can email images to you. Do you have any preference about whether the image is annotated in any way (e.g. with AR numbers?). I note using the time, date and initials in the file name and copying them to Lyn. Any preferred format for the file name? many thanks.
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