Three days ago (the 19th July 2022) we had some brief clear weather close to midnight and I was able to observe TX and AH Dra. Initially, I did look for RY and Z UMa in Ursa Major (The Big Bear) but it is now low down in the north and there was too much atmospheric extinction and twilight at that altitude for me to be able to make a decent estimate. The moon wasn't a problem at this time as it was two days from last quarter and hadn't risen.
Beginning with TX Dra which is easier to find (being close to Eta Dra) I found that I could, with my 7x50 binoculars, see stars K (=7.0 mag.), N (=7.7 mag.) and P (=8.4 mag.) on BAA chart 106.03. This meant my limiting visual magnitude was fainter than 8.4. At 22:34 UT I estimated that TX was fainter than K but brighter than N but closer in brightness to N. So my estimate was K(2)V(1)N which made it magnitude 7.5 (to one decimal place).
Going on to AH Dra, I found that the star was fainter than the star labelled 1 (=7.1 mag.) but brighter than the star labelled 8 (=8.4 mag.) but not much brighter than 8. So my estimate was 1(3)V(1)8 which made it magnitude 8.1 (to one decimal place).
Both these estimates were in good agreement with other observers from the BAA and AAVSO.
All text and images © Duncan Hale-Sutton 2022
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