For colors, I noted white, yellowish-white and (??).  I easily saw AB at 105x, but needed to use the 10mm Plossl (211x) to see the faint b star near B. 
 

Both stars appear white and one wonders why they belong in Hercules, wedged as they are between Ophiuchus and Serpens Caput. This may explain why this striking pair has been missed by Hartung. 

Comments: It is truly remarkable how three of four clear nights of viewing can vary so much at the eyepiece and even from hour to hour. I have experienced heavy dew, followed by a gentle breeze, followed by more dew -all in the same hour.  I have also discovered that my early Norton's Star Atlas, which is the only star chart that includes many of these faint doubles, is quite inaccurate when depicting  both configuration and magnitudes, making recognition more difficult. I must return to computer generated charts. 

Ambience: This viewing session was held in a remarkably noisy world with a distant train shunting for nearly half an hour( Was this a trainee driver?) and cars patrolling the neighbourhood, causing me to pause, eyes closed,until they disappeared. I moved the Dob several times to avoid tree branches and was conscious of endless numbers of doubles still to be observed. The heavens as always are quiet and wait to reveal hidden beauties to the patient searcher. Eddy.