Follow-up optical photometry of flaring blazars S4 0954+65 and 1308+326 (AU CVn)

ATel #15399; Filipp Romanov (amateur astronomer, Russia)
on 24 May 2022; 22:23 UT
Credential Certification: Kirill Sokolovsky (kirx@scan.sai.msu.ru)

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Since the end of April 2022, I observed blazars S4 0954+65 and 1308+326 (AU CVn) remotely using 0.61-m f/6.5 corrected Dall-Kirkham robotic telescope (Lane, 2018, RTSRE, 1, 119) of Burke-Gaffney Observatory (Saint Mary's University in Halifax, Nova Scotia, Canada) with Astrodon photometric Johnson/Cousins filers B, V, Rc and Ic.

For measuring the brightness of S4 0954+65 I took information about the magnitudes of comparison stars from the WEBT photometric sequence. The brightest magnitudes were measured on May 9 (FITS images are available at the link) and May 13 (FITS images are available here):

 
2022-05-09 02:33:23 V= 13.41 
2022-05-09 02:39:14 B= 13.87 
2022-05-09 02:44:54 Rc= 12.83 
2022-05-09 02:50:32 Ic= 12.45 
 
2022-05-13 03:28:36 V= 13.60 
2022-05-13 03:34:27 B= 14.13 
2022-05-13 03:40:07 Rc= 13.02 
2022-05-13 03:45:45 Ic= 12.40 

I confirm the bright state on May 9 detected in gamma-rays by Fermi-LAT (ATel #15375); also Rc magnitude on May 13 corresponds the magnitudes from Colgate University data (ATel #15380).

For measuring the brightness of 1308+326 I used the AAVSO star chart and photometry table. The brightest magnitudes (almost as bright as reported in ATel #15334) were measured on May 4 (FITS images) and May 6 (FITS images):

 
2022-05-04 02:58:25 V= 15.14 
2022-05-04 03:04:17 B= 15.59 
2022-05-04 03:09:56 Rc= 14.75 
2022-05-04 03:15:34 Ic= 14.21 
 
2022-05-06 02:56:46 V= 15.11 
2022-05-06 03:02:38 B= 15.58 
2022-05-06 03:08:17 Rc= 14.68 
2022-05-06 03:13:54 Ic= 14.11 

Exposures were 300 seconds for each image, magnitude errors are between 0.01 and 0.05, the time is indicated in UTC for the middle of the exposure. All the data have been uploaded to the AAVSO International Database under my observer code RFDA.