Interesting reading. I decided to take a look tonight. All of my "observing" is with a camera. Then i study the results. And i think on this one, we may have a discussion here...
Here is the close up crop... and i have marked what i believe are the AB C and D stars...
North is Up, and East is to the left.
[Edit: Oops... re-doing. My original was marked incorrectly.]
[Edit: Here is image with no markings. I am going to do some measurements of angles and distances tomorrow and will then post an update...}
And here are the Stelle Doppie, and the WDS. The larger picture of these combos is known as WDS-23276-1638. And that object then contains STF-3012 and 3013.
Interestingly, These two STF objects seem to "share a star or two..."
I believe the "D" star (much fainter) is just to the right of the "C" star, and above the "AB" pair.
Could be wrong.... But the angles and all do seem to line up.
It will be interesting to hear what others may think...
Edited by dmdouglass, 11 October 2019 - 12:58 AM.