After extensive investigation, Bob Harwell and Don Westergren determined that erratic Dec motion during guiding was due to slight movement in the Dec pivot arm creating a situation for positive feedback from the shaft encoders. Don suggested a Belleville washer to act as a spring to keep the Dec arm stationary. The washer assembly was installed in mid-November and seems to have done the trick, though since the problem was intermittent time will have to tell.
With stabilized guiding Sina and some of his students took a Sloan g’, r’ and i’ image set of NGC 891 (at right) as well an H-alpha image set of the Horsehead nebula. Sina also took some H-alpha images of the Medusa and Rosette nebulae and had a brief go at M44 with the 200 lpm grating. Ross Salinger took some images of M45.
A meeting’s to be held in December to discuss cleaning more stuff out of the back room and to prioritize repairs on the building.
The flipped optical path is ready for use and awaits a focusing training run at F8 and hopefully a training run with the at F16 (with the Televue) to get ready for double star speckle imaging.